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Endocrine-disrupting compounds: A review of their challenge to sustainable and safe water supply and water reuse
Abstract
The relevance of endocrine-disrupting compounds as potential contaminants of drinking water is reviewed, particularly in the reuse of wastewater. Growing populations and increasing intensification of land and water use for industry and agriculture have increased the need to reclaim wastewater for reuse, including to supplement the drinking water supply. The variety of anthropogenic chemicals that have been identified as potential endocrine disruptors in the environment and the problems arising from their use as human and livestock pharmaceuticals, as agricultural chemicals and in industry are discussed. The potentially adverse impact of these chemicals on human health and the ecology of the natural environment are reviewed. Data for the removal of estrogenic compounds from wastewater treatment are presented, together with the comparative potencies of estrogenic compounds. The relative exposure to estrogens of women on oral contraceptives, hormone replacement therapy, and through food consumption is estimated. A brief overview of some methods available or under development for the assessment of estrogenic activity in environmental samples is provided. The review concludes with a discussion of the directions for further investigation, which include human epidemiology, methodology development, and wastewater monitoring.
... Environmental contamination by endocrine-disrupting chemicals (EDCs) is a global concern. The strong link between environmental matrices such as water and human health necessitates development of techniques that will eradicated the detrimental effects of EDCs in the environment (Buck Louis et al., 2014;Falconer et al., 2006;Jung et al., 2015;Lee, 2002;Rapport, 2001;Wee & Aris, 2017). EDCs are a wide range of chemicals of natural and synthetic nature, which have great potentials to elicit negative effects on the endocrine systems of living organisms, i.e., humans, aquatic, and wildlife (Arthur et al., 2019). ...
... EDCs with their corresponding family, types of use/function, and endocrine disruption effects are presented in Table 1. These organic pollutants alter the normal coordination function of endocrine or hormonal systems by direct action on the hormonal glands and pathways, interaction with hormonal receptors and steroid hormones, or mimicking hormones (Falconer et al., 2006;Jung et al., 2015;Wee & Aris, 2017). The hormonal system is a highly coordinated system with a high degree of specificity in terms of concentration of hormonal release, timing, and target organs, such that minimal alteration results in gross physiological distortions and adverse health effects (Tapia-Orozco et al., 2016). ...
Endocrine-disrupting chemicals (EDCs) are pollutants with adverse effects even at very low concentrations; they remain a major concern for water quality. There is a strong link between environmental matrices such as water, soil, and human health. This implies that releasing these pollutants into the environment gets to the human system through contaminated air, water, and food. EDCs pose adverse effects on the endocrine systems of humans and wildlife and act as agents that interrupt metabolism, transport, synthesis, secretion, or elimination of natural blood-borne hormones present in the human body, which are responsible for the development, reproduction, and homeostasis process. The molecular group known as an endocrine disruptor is extremely heterogeneous, including the usage of synthetic chemicals in industrial solvents, lubricants and their by-products (such as 1,2-dichloroethane, 17α-ethinylestradiol, 17β-estradiol, 2,4-dichlorophenol, acetaminophen, amoxicillin, antiretroviral, benzotriazole, bisphenol A, carbamazepine, ciprofloxacin, diclofenac, ibuprofen, ketoprofen, naproxen, paracetamol, phenol, tetracycline, metformin, etc. discussed in this work). Natural chemicals in food can also act as endocrine disruptors and some of these chemicals are toxic. Contaminants in water influence all living beings; therefore, to prevent health complications, improve water quality and make it safer in the ecosystem, water must be purified. The complex nature of EDCs has necessitated the development of suitable, robust, and more versatile removal techniques capable of producing the desired result in a very cost-effective manner. The first part of this review addresses source and occurrence of EDCs, available EDC treatment technologies and their drawbacks, and followed by the recent advances in sequestrating EDCs using natural, synthetic (metal–organic frameworks, nanoparticle/nanomaterials), and agricultural waste adsorbents. Influence of different operational parameters on the adsorptive removal of EDCs, mechanism of EDCs sequestration and thermodynamic studies were also discussed. We concluded by providing some useful insights, challenges, and future prospects to foster better efficiency of these adsorbents for EDCs removal to meet various industrial applications.
Graphical abstract
... Studies have shown that aquatic organisms exposed to this compound had alterations in several reproductive parameters, including sex ratio, resulting in the feminization of a population due its oestrogenic action (Huang et al. 2012;Virk et al. 2014;Zhang et al. 2018). In addition to the oestrogenic effects, BPA prevents the action of neurotransmitters, decreases heart rate and promotes lipid peroxidation and oxidative damage in the liver and kidneys of freshwater fish (Li et al. 2015;Faheem et al. 2017). Other metabolic changes related to BPA have also been reported in other vertebrates, including humans, such as atherosclerosis, heart disease, obesity, diabetes and cancer (Rancière et al. 2015;Seachrist et al. 2016;Stojanoska et al. 2017). ...
... In the present study, marked differences were observed in A. bimaculatus responses after subacute exposure to relevant environmental concentrations of E1 or BPA as well as the combination of both. Several studies have already shown that these compounds have oestrogenic effects on different freshwater fish species (Lei et al. 2013;Ankley et al. 2017;Faheem et al. 2017;Zhang et al. 2018;Guan et al. 2019), but our study is a pioneer in comparing the oestrogenic activity of these two substances combined and their influence on the reproduction of a neotropical freshwater fish. ...
In the last decades, oestrogenic compounds have often been reported in environmentally relevant concentrations in aquatic environments around the world. Most laboratory studies of oestrogens try to understand the effects of a single contaminant, but in natural environments, the effects may be quite different due to interactions with other compounds. The present study aimed to compare the action of oestrone (E1) and bisphenol-A (BPA), acting singularly and in combination, on the spermatogenesis of Astyanax bimaculatus. After exposure to 100 ng/L of E1, BPA and a mixture of the two for 15 days, our results showed that E1 and the E1 + BPA mixture significantly altered the number of spermatogenic cells. BPA presented high cytotoxicity when compared to other treatments. Analysis of the two oestrogenic compounds suggests that the E1 + BPA mixture has no additive or synergistic effects. Together, the results of the present study indicate that endocrine-disrupting chemicals (EDCs) analysed alone may behave differently than when administered with other substances.
... Water consumption in particular potable water increases every year due to population growth, urbanization, industrial development as well as changes in agricultural and land use practices [2]. One of the most serious problems faced by billions of people today is the availability of fresh water. ...
... Other than that, orange peel as an adsorbent has also been studied by Foo and Hameed [57] for the removal of methylene blue. The authors investigated the effects of initial dye concentration (50,100,200, 300, 400, and 500 mg/L) and pH (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12) at room temperature with the contact time of 48 h and adsorbent dosage of 0.20 g. The adsorption capacity of methylene blue was found to be 382.75 ...
This review covers various methods to remove, treat, and detect emerging contaminants (ECs) in water and wastewater. ECs have drawn the attention of many countries due to their potential threat to human health as well as the environment. They are found in many human everyday products that are continuously released into the environment and will accumulate over time. In order to remove ECs, a number of methods have been developed, which include adsorption, membrane technology, biological treatment, and advanced oxidation process. In addition, advances in detection techniques and instrumentation are now able to detect ECs in which they occur at low concentrations. All the removal, treatment, and detection methods will be covered in this review. The removal, treatment, and detection of ECs and their transformation products in water and wastewater are challenging tasks due to their complexity in water samples. Therefore, such information should be emphasized in order to improve the current methods and develop new advanced methods.
... In different locations of the world, clean water sources have become under increasing pressure due to population growth, contamination, and many other reasons that affect quality and quantity of water [1]. Thus, to overcome the projected water deficiency, many societies have devoted efforts to sustain water and look for alternative water sources. ...
... Thus, to overcome the projected water deficiency, many societies have devoted efforts to sustain water and look for alternative water sources. Wastewater recycling/reuse has attracted interest as an energy efficient and practical way for providing water suitable for agricultural, toilet flushing, and replenishing groundwater basins [1]. The level of wastewater treatment can be adopted to meet the intended use, for example recycled water for use in toilet flushing or landscape irrigation involves less sophisticated treatment than recycled water for drinking and agriculture purposes [2]. ...
Water reuse has become a worldwide necessity due to scarcity of fresh water supplies. Recently, advanced oxidation processes (AOPs) has been incorporated into water reuse treatment train to destroy residual organics in water before its discharge. Yet, the currently applied ultraviolet/H2O2 AOP is associated with high electrical demand by the UV process in addition to transport and storage problems of H2O2. Accordingly, the current work investigates the use of solar light/NB-TiO2 as an efficient AOP for water reuse industry. The technology was developed and tested for degradation of five contaminants of emerging concern (CECs) spiked in Milli-Q water and different wastewater. All CECs were successfully removed from individual and quinary systems, even in presence of natural levels of common inorganic quenching agents. Roles of different reactive species involved on the degradation of CECs were explored. Using mass spectroscopy, transformation products from CECs degradation were identified and degradation pathways were hypothesized.
... Therefore, direct sewage discharge into the environment causes many environmental problems and contributes to the eutrophication of aquatic lakes, as evidenced by Lake Abu Dakana in Central Sudan [5]. Besides that, there is no national policy mandating the reuse of all treated wastewater effluent, and little has been achieved in this direction [6]. ...
... Many anthropogenic activities near the sea cause EDCs to enter aquatic ecosystems. Various EDCs, including those from personal care items, pharmaceuticals, and chemically-treated consumer goods, have been found in effluents from wastewater treatment plants (Bergman et al., 2013;Falconer et al., 2006). Urban and agricultural runoff, stormwater, flows and urban runoff carrying medications and pesticides, are additional sources of EDCs. ...
Endocrine disrupting chemicals (EDCs) are toxic compounds that occur naturally or are the output of anthropogenic activities that negatively impact both humans and wildlife. A number of diseases are associated with these disruptors, including reproductive disorders, cardiovascular disorders, kidney disease, neurological disorders, autoimmune disorders, and cancer. Due to their integral role in pharmaceuticals and cosmetics, packaging companies, agro-industries, pesticides, and plasticizers, the scientific awareness on natural and artificial EDCs are increasing. As these xenobiotic compounds tend to bioaccumulate in body tissues and may also persist longer in the environment, the concentrations of these organic compounds may increase far from their original point of concentrations. Water remains as the major sources of how humans and animals are exposed to EDCs. However, these toxic compounds cannot be completely biodegraded nor bioremediated from the aqueous medium with conventional treatment strategies thereby requiring much more efficient strategies to combat EDC contamination. Recently, genetically engineered microorganism, genome editing, and the knowledge of protein and metabolic engineering has revolutionized the field of bioremediation thereby helping to breakdown EDCs effectively. This review shed lights on understanding the importance of aquatic mediums as a source of EDCs exposure. Furthermore, the review sheds light on the consequences of these EDCs on human health as well as highlights the importance of different remediation and bioremediation approaches. Particular attention is paid to the recent trends and perspectives in order to attain sustainable approaches to the bioremediation of EDCs. Additionally, rigorous restrictions to preclude the discharge of estrogenic chemicals into the environment should be followed in efforts to combat EDC pollution.
... They tend to alter normal endocrine and coordination functions through their action on hormonal glands (Falconer et al. 2006;Jung et al. 2015;Wee and Aris 2017). The level of coordination of hormonal system is very high with a very high specificity such that slight alteration in their concentration and timing result in massive distortions in their physiological properties leading to adverse health effects (Bai et al. 2016;Tapia-Orozco et al. 2016;Tursi et al. 2018). ...
Modification of the adsorbent surfaces has been considered a fascinating strategy that enhances biomass-based adsorption properties for efficient removal of organic pollutants. This is based on the attempt to replace the cost-ineffectiveness of the commercial activated carbon. The present study discusses different modification strategies and a review on modified biomass materials for the sorption of organic contaminants. Unlike previous literatures in the field, wider range of these pollutants are discussed in this study under different categories including pesticides (such as insecticides, herbicides, fungicides), pharmaceutical (e.g. analgesic and antipyretic drugs, antibiotic drugs, non-steroidal anti-inflammatory drugs and antimalaria drugs), and dyes (e.g. azo, xanthene, miscellaneous diagnostic, tri-aryl methane, and phenol-derived polymeric dyes). It was observed that the acid-activated Posidonia oceanica and HNO 3 -modified rice husk displayed the highest and lowest adsorption capacities of 2681.9 and 0.35 mg/g for removing Rhodamine B dye and methyl parathion pesticide, respectively. The mechanistic aspects of organic pollutants adsorption, their corresponding regeneration studies, and environmental challenges with chemical modifications are also discussed. The use of computational (optimization) models for modified biomass-based adsorbents to remove organic pollutants is devoid in previous reviews but discussed in the present study. To foster more advancement in this field, the concluding part presents various challenges and knowledge gaps for furthering research towards more realistic industrial implementations.
... On the other hand, threats to human health arises from ingesting estrogens via drinking water (un)intentionally mixed with treated wastewater or eating food irrigated by treated wastewater [33][34][35][36]. The likelihood of mixing treated wastewater with drinking water, intentionally or unintentionally, is zero in Kuwait as treated wastewater is not reused in any potable applications. ...
Estrogens are endocrine-disrupting chemicals that impact both human and animal health, even at very low levels. Fate of estrogens were evaluated for three municipal wastewater treatment plants (WWTPs) in Kuwait, through determination of estrogens concentrations in influent and effluent streams. The solid-phase extraction gas chromatography-mass spectrometry method was used for analysis of estrogens concentrations in wastewater. Obtained results indicated that concentration of estrogens in the influent streams ranged from 0.0 to 474 ng/L, while that in the effluent streams were between 0.0 to 233 ng/L. Both influent and effluent concentrations showed high variations around mean values. Total removal of estrogens were found to be 13%, 79%, 68%, for Kabd, Sulaibiya and Umm Al Hayman, respectively. Even with high influent loadings, Sulaibiya plant achieved the highest removal of all types of estrogens, except estrone. The obtained results demonstrated that WWTPs require upgrading/optimization to maximize estrogens' removal. The study also discussed the potential impacts of estrogens in treated wastewater reused as irrigation water and recommended that Kuwait urgently needs to develop regulations for estrogens discharges from WWTPs in order to prevent further pollution of marine environment and groundwater with estrogens.
... Some European countries, such as France, Italy, the Netherlands, and Spain, as well as American countries such as Brazil and the USA, had it confirmed by many researchers that there were no traces of estrogen found in drinking water [51][52][53][54][55][56]. However, in China, the presence of trace estrogens were found and evaluated (E1 (9.9 ng/L), E2 (0.1 ng/L), and EE2 (0.3 ng/L)) [57][58][59][60][61], whereas E1 and E2 were not detected in European countries (France and Spain) [61][62][63][64][65]. ...
Micro-pollutants especially estrogens, progesterone, androgens, glucocorticoids, and growth hormones, are biological and chemical impurities that find their way into natural aquatic environments in trace quantities (ng/L), and possess a significant disturbance by impacting human and aquatic life. Due to the significant progress in in the analysis and detection techniques, these trace elements have been observed and quantified in several studies. However, as a result of limited methods and management technology, the adverse effects by these micro-pollutants in surface and coastal water is largely unknown. For this study, the compounds of estrogens, progesterone, androgens, glucocorticoids, and growth hormones have been selected according to their high frequent detection value in environmental waters. The concentration of the selected steroid and hormones ranges from 0.1–196 ng/L (estrogens), less than 0.1 to 439 ng/L (progesterone), 0.06–86 ± 2 (androgens), less than 0.1 to 433 ng/L (glucocorticoids), and 26.6 ng/g to 100 ng/L (growth hormones), and their percentage of removal efficiency varies from less than 10% to 99%, as the measurement of compounds concentration was found to be very low. Here, we report that future studies are necessary to detect the entry routes of these compounds into the environmental water, as well as to explore the technological approaches which are able to resolve this issue permanently.
... In all vertebrate species as well as humans, androgens are not only responsible for primary reproductive functions, but also responsible for regulating male secondary sexual characteristic (SSC) which are associated with courtship behaviour and sexual dimorphism (Thomas et al., 1993;Hoffman & Kloas, 2010). Modulation of gonadal endocrine systems by exposure to EDCs will largely affect early life development of the gonads and urogenital tracts of vertebrates, which are hormonally regulated Wolf et al., 1999;Falconer et al., 2006). Disruption of reproductive systems can therefore alter reproductive success and eventually fitness, general health and survival of exposed individuals. ...
Endocrine disrupting contaminants (EDCs) coming from households, industrial parks, wastewater (sewage) treatment and agricultural areas have been shown to pollute our freshwater systems. These contaminants may disrupt early development and reproductive systems in freshwater organisms (fish, frogs and crocodile species) as well as humans. Agricultural pesticides are shown as a large contributor to endocrine disruption activity in water catchment areas through spray drift, runoff, and/or groundwater leeching. Although South Africa is recognized as the largest consumer of agricultural pesticides in Africa, few studies have been undertaken to assess the prevalence and impact of endocrine disorders activities of pesticides in local freshwater systems. Recent studies have suggested that various agricultural pesticides, especially fungicides, might have adverse effects on the male endocrine system. There is therefore a need to test for a wider range of endocrine disrupting activities (mechanisms) in environmental waters other than conventional estrogenic (feminising) activities. Furthermore, there is a need to establish biomarkers in endemic species (bio-indicators) to show endocrine disruption in vertebrates (therefore also apply to humans). The specific objectives of the study were to: (1) describe and confirm the use of androgen-controlled breeding glands in male African clawed frogs (Xenopus laevis) as a biomarker for (anti)androgenic endocrine disruption activity (Chapter 2), (2) to investigate the premature development of breeding glands in X. laevis tadpoles (pre-metamorphic) and young froglets (post-metamorphic) (Chapter 2), (3) to investigate the disruption of male reproductive traits in adult X. laevis frogs by exposure to substances disrupting two different anti-androgenic endocrine disruption pathways (Chapter 3), (4) screen for (anti)androgenic activity of individual and binary mixtures of pesticides, which are regularly used in agricultural areas in the Western Cape Province of South Africa (Chapter 4), and (5) to test for (anti)androgenic and estrogenic endocrine disrupting activities by making use of in vitro assays as well as adult male X. laevis frogs collected from selected ponds surrounded by vineyards and fruit orchards in the Stellenbosch Winelands. The present study confirmed that male breeding glands can serve as biomarkers for (anti)androgenic endocrine disruption and that male reproductive and secondary sexual characteristics can be disrupted through two different biochemical control pathways. The study also confirmed that the expression of androgen-regulated breeding glands can be stimulated in pre-metamorphic tadpoles and immature, post-metamorphic frogs, and can thus be used for (anti)androgenic testing. The rapid testing and predictive value of an in vitro recombinant yeast screen for androgen receptor binding inhibition of selected individual or binary mixtures of pesticides was also confirmed. However, the current study showed that the predicted in vitro (anti)androgenic activity did not always correspond with in vivo (anti)androgenic biomarker outcomes. This It also confirmed that single-cell in vitro assays can be used as a first-level prediction for (anti)androgenic activities of individual or mixtures of agricultural pesticides. This study provides a better understanding for potential mixture interactions of commonly used agricultural pesticides, the hormonal control of secondary sexual characteristics in male frogs and the use of reproduction biomarkers to study long-term effects of endocrine disruptors in local water supplies.
... The presence of emerging contaminants in the environment constitutes a challenge for human and environmental health; especially in relevance to endocrine disruption (Falconer et al., 2006;Vieira et al., 2021). Bisphenols (BPs) and benzophenone UV-filters (BzPs) are two chemical classes of emerging contaminants, which are also commonly referred to as plasticizers and ultraviolet filters, respectively, and are Science of the Total Environment 813 (2022) 152571 used as additives in plastic formulations and personal care products due to their physicochemical properties (Asimakopoulos et al., 2016a,b;Castro et al., 2019;Kim and Choi, 2014;Liao and Kannan, 2013;Regueiro et al., 2015). ...
Bisphenols and benzophenone UV filters are contaminants present in a wide variety of plastic materials and consumer products. The scientific attention towards these contaminants has increased in recent years due to their presence in microplastics, their ubiquitous occurrence in the environment, and their known endocrine disrupting health effects. In this study, the occurrence of nine bisphenol analogues and five benzophenone UV-filters was assessed in wild brown mussels (Perna perna) collected from different sampling sites along the coast of Algoa Bay, South Africa. Eleven out of fourteen target contaminants were detected, and bisphenol AP (BPAP) was detected for the first time in mussels, presenting the highest median concentration of 150 ng g⁻¹ dry weight (d.w.) and a detection frequency of 91%. Regarding benzophenone UV-filters, median concentrations of the analogues ranged from 2.01 to 10.6 ng g⁻¹ d.w., with benzophenone-1 (BzP-1) and benzophenone-3 (BzP-3) presenting the highest concentrations. Human exposure was assessed by Estimating Daily Intakes (EDI) of the target contaminants through mussel consumption. To our knowledge, this is the first study from the African continent on the occurrence of bisphenols and benzophenone UV-filters in a large population (n = 138) of wild brown mussels.
... These new emerging pollutants can also convert into chiral metabolites, which are receptor-specific and cause acute side effects. As the world is suffering from a global pandemic of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), water pollution by these emerging contaminants has now become a major subject of global concern [65][66][67]. Naproxen is a non-steroidal anti-inflammatory drug (NSAID) that decreases various pain and inflammation-causing hormones [68,69]. A novel method was developed to eliminate naproxen from the aqueous medium by modifying nanoclay with β-cyclodextrin and then polymerizing it with polyvinylpyrrolidone (PVP) to produce more surfaces for higher adsorption. ...
Bionanotechnology combines biotechnology and nanotechnology, which utilizes
bionanomaterials, nanosized materials made up of various biological entities.
Bionanomaterials are referred to as state-of-the-art materials as they can be utilized
in multiple domains like aeronautics, agriculture, environment, energy, etc. They are
also known to cover the gap between molecular approaches and traditional microtechnology. Several bionanomaterials have been utilized for applications in agriculture and environment domains for air, water and soil pollutant detection,
remediation of heavy metals, and act as biopesticides, insecticides, etc, to prevent
crop and soil damage. Hence, this chapter introduces various potentialities of
bionanomaterials in agricultural and environmental domains.
... 12 Therefore, fish are considered as indicator organisms to assess the EDCs 13 which imitate the effects of natural oestrogens (xenoestrogens). 14,15,16,17 Mostly heavy metals, pesticides and insecticides acts as EDCs individually or synergistically and become toxic to the organisms. This in turn affects survival, growth and reproduction of organisms. ...
Environmental monitoring is a recent world-wide approach to save the future in line. The present study focuses on toxicity of heavy metals and pesticides on the freshwater aquarium fish (Poecilia reticulata and Poecilia sphenops). The study intense on drawing the acute and chronic safe levels of metals and pesticide exposed to 96 h and 28 day respectively. On exposure, the fish were observed to be under stress and showed excitability. It was observed that both species were highly sensitive to arsenic and cypermethrin, meanwhile resistant to cadmium and chlorpyrifos. The acute safe levels for As irrespective of species was comparatively lesser than that of Cd exposed fish and the range of safe values for pesticides exposure were between 0.018 and 0.059 ppb. As the water quality is influencedby many environmental factors, the present study helps the aquarist in monitoring the safe level of toxicants in the medium. This in turn increases the economic growth of the aquarist.
... This is because of their countless adverse health and ecological effects as well as their increased domestic, industrial, and commercial applications, which increase their concentrations in water resources. They reach groundwater following direct discharge, accidental spills, domestic use, industrial effluents, and agricultural runoff (Tapia-Orozco et al., 2016), (Falconer et al., 2006). Subsequently, the consumption and distribution of these compounds in several crops of fruits and vegetables have been detected signifying a substantial possible exposure to humans (Lu et al., 2015). ...
Endocrine-disrupting chemicals (EDCs) target the endocrine system by interfering with the natural hormones in the body leading to adverse effects on human and animal health. These chemicals have been identified as major polluting agents in wastewater effluents. Pharmaceuticals, personal care products, industrial compounds, pesticides, dyes, and heavy metals are examples of substances that could be considered endocrine active chemicals. In humans, these chemicals could cause obesity, cancer, Alzheimer's disease, autism, reproductive abnormalities, and thyroid problems. While in wildlife, dysfunctional gene expression could lead to the feminization of some aquatic organisms, metabolic diseases, cardiovascular risk, and problems in the reproductive system as well as its levels of hatchability and vitellogenin. EDCs could be effectively removed from wastewater using advanced technologies such as reverse osmosis, membrane treatment, ozonation, advanced oxidation, filtration, and biodegradation. However, adsorption has been proposed as a more promising and sustainable method for water treatment than any other reported technique. Increased attention has been paid to biodegradable polymers and their nano-composites as promising adsorbents for the removal of EDCs from wastewater. These polymers could be either natural, synthetic, or a combination of both. This review presents a summary of the most relevant cases where natural and synthetic biodegradable polymers have been used for the successful removal of EDCs from wastewater. It demonstrates the effectiveness of these polymers as favorable adsorbents for novel wastewater treatment technologies. Hitherto, very limited work has been published on the use of both natural and synthetic biodegradable polymers to remove EDCs from wastewater, as most of the studies focused on the utilization of only one type, either natural or synthetic. Therefore, this review could pave the way for future exploration of biodegradable polymers as promising and sustainable adsorbents for the removal of various types of pollutants from wastewater.
... An ultraviolet filter is often used in personal care products as the primary component of preventative products. Studies have shown that it can bioaccumulate in fish, interfere with endocrine hormones (Li et al., 2007) and expose fish species to synthetic estrogen, leading to the feminization of male fish species (Falconer et al., 2006). With the progress of science and technology and the continuous innovation of instruments and equipment, more sophisticated instruments can be used to detect the types and contents of pollutants in water. ...
Reclaimed water is an important alternative water supply because it solves the water shortage problem. This manuscript is intended to provide a critical review of recent publications that address future reclaimed water requirements and analyze and visualize historical trends, research hot topics and promising future research directions. The results show that treatment technologies and optimized system designs for reclaimed water were early topics of interest. However, in the current era, "climate change," "sustainability," "technology," "impact" and other keywords appear frequently as the hot topics. Specifically, emerging research topics include (1) the influence of climate change on water quality and water supply system optimization under uncertainty, (2) improving public acceptance and strengthening water management and policy implementation, (3) developing and applying cost-effective treatment technologies for the removal of trace pollutants and (4) more comprehensive health risk assessment and online detection technology. This analysis accurately reflects historical trends in the field and will help researchers choose future research topics.
... Every year, thousands of tons of pharmaceuticals are consumed in human and veterinary medicine to treat diseases, infections as well as to prevent pregnancy, and during several agricultural and aquaculture practices (Jurgens et al., 2002;Barbier, 2011). Several studies reported the presence of more than 80 pharmaceutical products such as hormones in the effluents of wastewater treatment plants and those of municipal discharge, as well as urban and agricultural runoff (Layton et al., 2000) of several industrialized countries (Bitman and Cecil, 1970;Filali--Meknassi et al., 2004;Falconer, 2006;Pépin, 2006;Clouzot et al., 2008). The lack of knowledge about the fate in the environment, the regulations, their potentially harmful effects on ecosystems and human health became a topical subject for scientists. ...
An experimental study was carried out to determine the effects of the enrichment of sediments by endocrine perturbators on free-living nematodes from the Ghar El Melh lagoon, Tunisia. For 30 days, four concentrations of Estradiol Benzoate (hereafter EB) (0.43, 4.3, 8.6 and 12.9 ng.l⁻¹). The average nematode abundances showed a significant increase after the introduction of EB in their close environment. In contrast, the taxonomic examination has shown a decrease in species diversity of nematodes. The ordination of treatments according to the nMDS showed a clear structural separation of the enriched replicates with EB from controls based on species lists, in particular for concentrations EB3 and EB4. Indeed, under such conditions, the nematofauna exhibited a more remarkable presence of a new record for Science Theristus n. sp. and a decrease in relative abundances of Paracomesoma dubium. On feeding level, a predominance of non-selective deposit-feeders and a decline in proportions of epistrate feeders and carnivorous omnivores was observed with increasing concentrations of EB. Furthermore, in treated replicates with EB, females discernibly showed an increase compared to controls. Overall, EB affect significantly features of meiobenthic nematodes starting from the concentration of 4.3 ng.l⁻¹.
... Human health and ecological concerns associated with IPR and unplanned water reuse typically focus on the impacts of discharged pathogens, nutrients, micropollutants and endocrine disruptors on receiving water quality 37,43,45,46 . These water reuse practices also have the potential to exacerbate the FSS. ...
Inland freshwater salinity is rising worldwide, a phenomenon called the freshwater salinization syndrome (FSS). We investigate a potential conflict between managing the FSS and indirect potable reuse, the practice of augmenting water supplies through the addition of highly treated wastewater (reclaimed water) to surface waters and groundwaters. From time-series data collected over 25 years, we quantify the contributions of three salinity sources—a water reclamation facility and two rapidly urbanizing watersheds—to the rising concentration of sodium (a major ion associated with the FSS) in a regionally important drinking-water reservoir in the Mid-Atlantic United States. Sodium mass loading to the reservoir is primarily from watershed runoff during wet weather and reclaimed water during dry weather. Across all timescales evaluated, sodium concentration in the reclaimed water is higher than in outflow from the two watersheds. Sodium in reclaimed water originates from chemicals added during wastewater treatment, industrial and commercial discharges, human excretion and down-drain disposal of drinking water and sodium-rich household products. Thus, numerous opportunities exist to reduce the contribution of indirect potable reuse to sodium pollution at this site, and the FSS more generally. These efforts will require deliberative engagement with a diverse community of watershed stakeholders and careful consideration of the local political, social and environmental context. Freshwater salinization syndrome is an emerging threat to freshwater globally. Here the authors quantify the contribution of indirect potable reuse to sodium pollution and suggest a variety of behavioural and technological interventions to address this growing environmental problem.
... Effluents of wastewater treatment plants (WWTPs) contain a variety of chemicals such as surfactants, pesticides, industrial materials, the human estrogens estrone (E1), 17β-estradiol (E2), and estriol (E3), and the pharmaceutical estrogen ethinylestradiol (EE2), also known as the birth control hormone, which possess estrogenic activity [3]. To date, there are more than 50 chemicals from industrial, municipal, and agricultural sources that are known to interfere with endocrine systems of wildlife [4][5][6]. ...
Wastewater treatment plant effluents contain a variety of endocrine disrupting chemicals (EDCs), including chemicals with estrogenic activity such as 17β-estradiol (E2), 17α-ethinyl estradiol (EE2), and nonylphenols. These substances can affect both behavior and physiology in vertebrate animals. To explore the presence and effects of these EDCs in a natural setting, juvenile and adult male fathead minnows, Pimephales promelas, were held in cages upstream and downstream of the effluent site of a wastewater treatment plant for 21 days and subsequently tested for changes in reproductive behaviors and production of vitellogenin. Additionally, estrogenic activity in the stream was measured using a yeast bioassay. Estrogenicity was found to be significantly higher downstream of the wastewater effluent when compared to levels upstream. Vitellogenin levels did not show a correlational pattern with levels of estrogenicity in the water, but two measures of reproductive behaviors occurred significantly less often in downstream males than upstream males. This suggests that a brief (three-week) exposure to stream water containing wastewater treatment plant effluent can bring about changes in reproductive behavior of fish and that behavior may be more sensitive to low levels of environmental endocrine disruptors than vitellogenin production.
... The natural sex hormone estradiol and its metabolites (estrone and estriol) and the synthetic steroid ethinylestradiol are excreted in the urine of mammals and can be found in surface and ground waters. Other EDCs, such as the alkylphenols-nonylphenol, bisphenol A and pentachlorophenol are derived from industrial and domestic activities and also occur in environmental waters [1][2][3][4][5][6][7]. Bisphenol A (BPA) is a chemical that has been attracting increased attention because of its high potential for human exposure. ...
Rivers as surface water in Malaysia are recipients of effluents and wastewater and yet it is important water source for daily uses of some villagers living along the river. Endocrine disruptors such as Bisphenol A (BPA) can be found in river due to continuous discharge into it. The objectives of this research is to find out the occurrence and concentration of BPA in Sungai Langat and also to see how water quality parameters such as temperature, pH, dissolved oxygen (DO), turbidity, Total Suspended Solid (TSS), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD) and ammonia nitrogen (AN) affecting the concentration of BPA. 12 stations in total including upstream to downstream of Sungai Langat and also tributary of Sungai Langat. The instrument used to find out concentrati on of BPA is Triple Quadrupole LC/MS. The source of BPA are mainly industrial effluents and also direct domestic discharges. The water quality parameters that will affect concentration of BPA are Ammonia Nitrogen (AN), turbidity, Biochemical Oxygen Demand (BOD), Total Suspended Solid (TSS), and Chemical Oxygen Demand (COD), Dissolved Oxygen (DO). While pH and water temperature are also factors that will affect concentration of BPA but the significance is not shown in the analysis. It can be concluded that u pstream of Sungai Langat has lower concentration of BPA than downstream .
... Utmost care should be taken for the disposal of drugs like endocrine disruptors, heavy metals, and other compounds that are dangerous for surroundings. 4 If these wastes are not properly guarded it may be misused by some people that lead to health-related issues. Chemicals cause surroundings damage which is mainly present in the toiletry products. ...
The current appraisal aims to educate and give valuable information about disposal methods adopted in hospitals and health sectors. Many healthcare departments like microbiology labs, pharma industries, medical agencies, healthcare sectors all produce waste which usually contains unsafe materials that should not be exposed untreated to the atmosphere. In these health sectors, many types of wastes are separated as lab debris, chemical, and biological waste. These waste are rich in contaminants and pathogenic microbes which will be more lethal if they are not properly disposed of. The authors describe the various wastes and the definite discarding process to minimize costs and impact on the surroundings. Presently many of these sector professionals have some difficulty in disposal, these issues can be overcome by the systematic and easy plan described by the authors. Specific treatment must be required for this waste before they disposed off. This waste must be washed before introducing them into a particular disposable discard. Medical waste can be disposed of thoroughly as they contain infectious or non-infectious microorganisms. Biological and pharmaceutical waste must be disposed of, to prevent environmental hazards. Among the various approaches adopted for the disposing of these waste includes incineration, autoclaving, chemical disinfection, ignitability, etc. are popularly adopted. Each particular waste can be disposed of in a specific manner. The authors succeed in bringing the systematic approach in the disposal of waste in health care units and concludes that proper disposal is important to reduce the contamination and pollution of the environment and maintain a healthy atmosphere.
... These EDCs may disrupt these processes by interfering with the production, release, transport, metabolism, binding, action, or elimination of natural hormones in the body responsible for the maintenance of homeostasis and the regulation of developmental processes or by blocking these hormone receptors, thereby triggering or preventing hormonal response (Karlock et al., 1996;Hotchkiss et al., 2008;Markey et al., 2001;Pedersen et al., 1999;Witorsch, 2002). Chemicals implicated as having endocrine disrupting effects include; biocides, industrial compounds, surfactants, and plasticizers including bisphenol A (BPA) (Eskinazi et al., 2003;Falconer et al., 2006;Hayes et al., 2002;Markey et al., 2003;Renner, 1997). ...
This study was carried out to determine the effect of storage time and storage temperature on BPA leaching in plastic containers. The indirect competitive enzyme-linked immunosorbent assay (ELISA) method was used for the determinations; the limit of detection (LOD) is 10pg/ml. The results revealed that there was a reduction in the concentration of BPA in tap water samples stored in plastic containers at temperature > 30 0 C for sixty days compared with their initial BPA concentrations, in contrast there was an increase in BPA concentrations of water samples stored in plastic containers at 2-8 0 C (refrigerated) and 25-27 0 C (room temperature) for sixty days when compared with their initial BPA concentrations. This study revealed that leaching of BPA from plastic materials increases with time of storage, while BPA degradation in plastics increases with increase in temperature. Hence the use of plastics house wares and storage of foods and drinks in plastic containers should be minimised in order to reduce human exposure to BPA.
... These are defined as exogenous chemicals or chemical mixtures that impact endocrine system structure or function and cause adverse effects [2]. Chemicals implicated as having endocrine disrupting effects include; biocides, industrial compounds, surfactants, and plasticizers which include Bisphenol A (BPA) [3][4][5][6][7]. ...
Fish, being one of the most abundant groups in the aquatic ecosystem are sometimes exposed to all sorts of environmental assaults such as heavy metal pollution and agricultural chemicals contamination, which can consequently have serious effects on the nutritive quality of fish inhabiting the contaminated aquatic environment. This study investigated the level of Bisphenol A (BPA) (a known endocrine disruptor) in the serum of Cat fish (Clarias gariepinus and Clarias nigrodigitatus) obtained from different ponds, rivers and lagoons in south western Nigeria, using the indirect competitive enzyme-linked immunosorbent assay (ELISA) method. The limit of detection (LOD) of the kit was 10pg/ml. BPA was found in all fish samples caught (ranging from 0.05±0.01µg/L-2.76±0.97µg/L), with pond raised fishes having the highest BPA concentrations. Analysis of serum total cholesterol levels in the Cat fish revealed that Cat fish caught from lagoons had a significantly (p<0.05) higher serum total cholesterol levels compared with the others, no correlation was found between serum total cholesterol and serum BPA concentration in the fishes. The study also revealed there was no significant association between BPA concentrations (6-52µg/L) in the water samples and the physicochemical properties of the water samples from which the fishes were obtained. Contamination from aquatic environment is a major source of BPA exposure in fishes, hence there is need for regular monitoring of our aquatic environment and effective methods of waste disposal should be adopted to reduce the level of contaminants in these aquatic environment.
... In addition to the above problems, drugs and pharmaceutical ingredients and residues transform into chiral metabolites, which are receptor specific and impose acute side effects. Water pollution by these emerging contaminants is becoming a subject of global concern, due to the measurable threats and disturbances of ecosystems [39,40]. Thus the elimination of these drugs and pharmaceutical residues in water is of vital importance prior to the supply of pure water to the community. ...
One of the most prevailing problems worrying people throughout the world is insufficient access to drinking water and sanitation. The treatment of wastewater, in order to bring it back to a reusable form, is highly essential for future demands. In recent years, water purification methods have been the focus and attention of many scientists and governmental agencies. Different methods have been used to treat wastewater, and a combination of an advanced nanotechnology-oriented approach with conventional methods has offered interesting benefits. Bionanocomposite materials, due to their green and biodegradable nature, are the most promising materials for water remediation, that is, the removal of microorganisms, organic pollutants, heavy metals, etc. from contaminated water. In this chapter, important biopolymer-based bionanocomposites, including clay hydrogel nanocomposites, gum polysaccharide-based bionanocomposites, chitosan-based polymer bionanocomposites, cellulosic nanocomposites, and their applications in wastewater treatment have been described. The chapter also focuses on the fact that multidirectional research is required to accelerate the application of bionanocomposites at a large scale for the effective elimination of various types of pollutants from wastewater.
... The rising world population and urbanization has led not only to an increased need for drinking water, but also large quantities of discharged wastewater. Consequently, recycle and reuse of wastewater is of growing importance [1,2]. Treated wastewater can enter reservoirs which provide raw water feed to a water treatment facility. ...
As the demand for potable water increases, direct potable reuse of wastewater is an attractive alternative method to produce potable water. However, implementation of such a process will require the removal of emerging contaminants which could accumulate in the drinking water supply. Here, the removal of atrazine, a commonly used herbicide, has been investigated. Using real and synthetic wastewater, as well as sludge from two wastewater treatment facilities in the United States in Norman, Oklahoma and Fayetteville, Arkansas, atrazine removal has been investigated. Our results indicate that about 20% of the atrazine is removed by adsorption onto the particulate matter present. Significant biodegradation of atrazine was only observed under aerobic conditions for sludge from Norman, Oklahoma. Next-generation sequencing of the activated sludge revealed the abundance of Noncardiac with known atrazine degradation pathways in the Norman aerobic sludge, which is believed to be responsible for atrazine biodegradation in our study. The detection of these bacteria could also be used to determine the likelihood of biodegradation of atrazine for a given wastewater treatment facility.
... Among these, environmental endocrine disruptors (EDCs), as mostly persistent organic pollutants (POPs), are bioaccumulative, highly toxic, have low concentration, and latent. They can get into the human body directly or indirectly through the food chain and were enriched and amplified in the living organism [1,2]. As a result, research on the governance of EDCs has become a widespread concern in the environmental field. ...
Abstract In the present work, a tubular nano-copper sulfide was successfully synthesized by hydrothermal method. The physical and chemical properties of the prepared materials were characterized by XRD, SEM, TEM, and BET. The synthesized copper sulfide was used as an adsorbent for removing 17α-ethynyl estradiol (EE2) and exhibited excellent adsorption properties. At 25 °C, 15 mg of adsorbent was applied for 50 mL of 5 mg/L EE2 solution, adsorption equilibrium was reached after 180 min, and the adsorption rate reached nearly 90%. In addition, the kinetics, isothermal adsorption, and thermodynamics of the adsorption process were discussed on the basis of theoretical calculations and experimental results. The theoretical maximum adsorption capacity of copper sulfide was calculated to be 147.06 mg/g. The results of this study indicated that copper sulfide was a stable and efficient adsorbent with promising practical applications.
... The presence of steroid estrogens in drinking water has also been evaluated, with the drinking water of mainland China reported to contain traces of E1 (n.d.-9.9 ng/L), E2 (n.d.-0.1 ng/L), and EE2 (n.d.-0.3 ng/L) (Fan et al. 2013;Zhang et al. 2011;Zhang et al. 2013). However, European (France, Italy, Spain) and American countries (Brazil and the USA) had no traces of estrogen in drinking water (Devier et al. 2013;Maggioni et al. 2013;Esteban et al. 2014b;Wang et al. 2011;Jardim et al. 2012;Falconer et al. 2006). In these studies, testosterone was only detected in China's (n.d.-480 ng/L) and Brazil's (n.d.-329 ng/L) groundwater and drinking water ( Yang et al. 2014a;Montagner et al. 2019). ...
The common steroid hormones are estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2), and testosterone (T). These steroids are reported to contaminate the environment through wastewater treatment plants. Steroid estrogens are widespread in the aquatic environment and therefore pose a potential risk, as exposure to these compounds has adverse impacts on vertebrates. Excessive exposure to steroid estrogens causes endocrine disruption in aquatic vertebrates, which affects the normal sexual life of these animals. Steroid pollutants also cause several health problems in humans and other animals. Microbial degradation is an efficient method for removing hormone pollutants from the environment by remediation. Over the last two decades, microbial metabolism of steroids has gained considerable attention due to its higher efficiency to reduce pollutants from the environment. The present review is focused on the major causes of steroid pollution, concentrations of these pollutants in surface water, groundwater, drinking water, and wastewater, their effect on humans and aquatic animals, as well as recent efforts by various research groups that seek better ways to degrade steroids by aerobic and anaerobic microbial systems. Detailed overview of aerobic and anaerobic microbial biotransformation of steroid estrogens and testosterone present in the environment along with the active enzyme systems involved in these biotransformation reactions is described in the review article, which helps readers to understand the biotransformation mechanism of steroids in depth. Other measures such as co-metabolic degradation, consortia degradation, algal, and fungal steroid biotransformation are also discussed in detail.
... Several studies have indicated that the main part of estrogen pollution comes from point sources (Auriol et al. 2006;Schiliró et al. 2009;Bolong et al. 2009;Caliman and Gavrilescu (2009) ;Falconer et al. 2006;Pereira et al. 2011;Prasse et al. 2015). In addition, these case studies showed behavioral and morphological difference in aquatic fauna downstream from estrogen-containing effluent discharges. ...
17β-Estradiol (E2) is a natural estrogen produced by the feminine endocrine system. It is excreted mainly through urine and feces. Exposure to E2 may affect the reproductive system of both animals and humans, especially since the removal of E2 in conventional processes and technologies present in the wastewater treatment plants is not sufficient. Chlorine is one of the most studied and used oxidant worldwide. Although there are studies that demonstrate the endocrine disrupting compounds removal like E2, its reaction with organic matter can originate by-products, namely, trihalomethanes, which are known to have high toxic potential. The main aim of the present study was to evaluate the removal of E2 (50 μg E2 L⁻¹—maximum concentration) using peracetic acid (PAA), a seeming cleaner and innocuous alternative to chlorine. To this end, a series of jar tests were performed, using different peracetic acid concentrations (1, 5, 10, and 15 mg L⁻¹) and contact times (10, 15, and 20 min). The results obtained showed that a peracetic acid concentration of 15 mg L⁻¹ with a contact time of 20 min had a removal efficacy of approximately 100%. The second main goal of this study was to evaluate the ecotoxicological potential of the tested treatments on the zebrafish Danio rerio. Several oxidative stress biomarkers were evaluated, namely glutathione S-transferase, lipid peroxidation, and catalase, besides vitellogenin. Both peracetic acid and E2 caused significant increases in the oxidative stress biomarkers, although this did not lead to increased lipid peroxidation levels. In addition, peracetic acid significantly decreased the estrogenic activity of E2, as indicated by decreased vitellogenin levels. Peracetic acid demonstrated to have great potential as an alternative disinfectant for chlorine treatments, and indications for future research are discussed.
The addition of powdered activated carbon (PAC) and a coagulant during the coagulation-flocculation process is an easy and common option for tackling pollution peaks from organic micropollutants (OMPs) in the production of drinking water. However, the adsorption-desorption mechanisms during this process have not been thoroughly explored. Thus, this research aims to study the mechanisms involved and the impact of the operating conditions when PAC and coagulant are simultaneous used. A commercial PAC with a BET-specific surface area of 961 m²/g, and ferric chloride (FeCl3) were added simultaneously to three different waters spiked with 15 OMPs (pesticides and pharmaceuticals). Different parameters such as PAC and coagulant dosage, pH, contact time and the nature/content of the natural organic matter (NOM) were examined. Results showed that using coagulant + PAC reduced OMP adsorption efficiency, whereas increasing PAC dosage and extending contact time enhanced OMP removal efficiency. Furthermore, a high concentration of NOM affected micropollutant adsorption by competing for adsorption sites. This study highlights for the first time an unexpected phenomenon that significantly affects overall efficiency: i.e. OMPs adsorbed during the slow mixing step that desorbed during the sedimentation step. Desorption sometimes reduced by >30 % the overall efficiency of OMP removal. The parameters that affected efficiency loss were pH, contact time, NOM concentration, and PAC and FeCl3 dosage. Some operational adaptations could be considered regarding these parameters to avoid or reduce desorption, making the process more cost-effective.
The presence of volatile organic compounds (VOCs) in drinking water has the potential to harm human health and undermine public confidence. Hence, this is the first study to comprehensively investigate concentrations of 25 VOCs in the 146 drinking water treatment plants (DWTPs) in 24 cities across seven major river basins (including the Yangtze River, Yellow River, Haihe River, Songhua River, Liaohe River, Pearl River, and Huaihe River), China. The occurrence, human health, and olfactory risks, as well as removal efficiency of VOCs in DWTPs, were evaluated. The findings revealed that 21 VOCs were detected, with concentrations ranging from not detected to 99.10 μg/L (trichloromethane). The maximum concentrations of trichloroacetaldehyde (54.90 μg/L) and trichloromethane (99.10 μg/L) exceeded China's regulated values (GB 5749–2006/2022). The concentrations of VOCs and water quality parameters showed a strong positive correlation. Human health and olfactory risks assessment indicated that drinking water exposures do not pose carcinogenic (CR < 10⁻⁶) and non-carcinogenic (HI < 1) health risks to consumers, nor do olfactory and taste hazards (OHI <1). However, it is worth mentioning that due to the relatively high concentrations of some VOCs (trichloroacetaldehyde, acrolein, and trichloromethane), the health risk posed by them are still a major concern that needs to be addressed. Finally, the removal efficiency of VOCs is low in 146 DWTPs (mean of 12.91%–76.79%). Taken together, adding advanced treatment procedures for the purpose of improving the removal efficiency of pollutants of DWTPs in the future is an urgent priority.
In this study, the magnetic urchin‐like NiCo2O4 materials (NiCo2O4‐w) were successfully prepared from the waste during the preparation of NiCo2O4/carbon cloth composite, and further evaluated as a peroxymonosulfate activator for removing bisphenol A (BPA). The effect of various factors such as initial solution pH, peroxymonosulfate (PMS) concentration, catalyst concentration and coexisting ions on the BPA removal were evaluated. The optimal factors were 0.20 g L−1 catalyst, 0.10 g L−1 PMS, 7.14 pH (unadjusted). Moreover, the NiCo2O4‐w exhibited good catalytic effects over wide ranges of pH (3.73 to 12). SO42‐ and H2PO4‐ remarkably inhibited the BPA removal, NO3‐ obviously inhibited the BPA removal, while Cl‐ and HCO3‐ had a little effect on the BPA removal. Singlet oxygen (1O2), superoxide radical (O2• –), hydroxyl radical (•OH) and sulfate radical (SO4• –) participated in the BPA degradation, of which O2• – and 1O2 played the leading role, especially O2• –. Oxygen vacancies, redox cycling pairs of Co(III)/Co(II) and Ni(III)/Ni(II) were responsible for PMS activation. Moreover, the degradation routes of BPA were rationally put forward. This present work not only presents that NiCo2O4‐w has a low‐cost, magnetically recoverable catalyst for high efficient degradation of wastewater containing BPA, but also opens up a new avenues to reduce environmental problems associated with waste treatment during the preparation of heterogeneous catalyst. This article is protected by copyright. All rights reserved.
Micro pollutants are chemical substances which are generated through natural as well as human activities. The anthropogenic sources of micro pollutants are so far greater than natural processes. These micro pollutants are present in diverse forms, e.g., pharmaceuticals, heavy metals, personal care products, and endocrine disrupting chemicals. The nature of their toxicity also ranges from mild to very chronic for the human health as well environmental dysfunctions. This chapter also deals mainly with the amount of the micro pollutants released, their main sources, toxicity ranges, and the way these pollutants produce ill impacts on the human health. It has been observed that all micro pollutants having any source can produce their adverse impacts on the health of humans, and these impacts include DNA mutation to organ modification, with the outbreak of certain diseases of which liver, lung, and kidney diseases are prominent. The possible pathway of these pollutants has been observed in the form of drinking or wastewater which enter in to human body through irrigating the fruits or foods and by drinking the water having such pollutants. The objective of this study is also to employ all possible options by which these pollutants could be eliminated completely from the environment. There are certain options which can be used for their reduction very simple to last techniques. This study also stresses to minimize all possible sources of these micro pollutants rather than to use possible option for their elimination once they enter in to the environment.
The aim of this PhD thesis was to develop and assess the potential of novel zebrafish (zf)- based in vitro and in vivo reporter gene assays as bio-analytical tools to monitor estrogenic activity and their implementation in effect-directed analysis (EDA) approach to identify fishspecific
estrogenic compounds in complex mixtures. For this purpose, we first characterized the response of the assays towards a panel of (xeno)estrogens, revealing differences in the affinity of zebrafish estrogen receptor (zfER) subtypes to (xeno)-estrogens. Comparison with human cell-based (MELN-hERα) assay further highlighted inter-species differences showing different chemical ranking towards different classes of known ER ligands. Then, application of these tools to different environmental matrices demonstrated for the first time their functionality to detect and quantify estrogenic activity in complex mixtures, highlighting the zfERβ2 assay as the most sensitive among the different in vitro zfER assays. The above in vitro estrogenic activity was also confirmed in vivo at the most contaminated sites by using the EASZY assay, further adding eco-toxicological relevance. Interestingly, we also reported zebrafish-specific activities at several sites that were not active by the human MELN assay, suggesting the occurrence of fish-specific ER ligands. To address this hypothesis, we applied our zebrafish tools in specific higher tier-EDA studies that allowed isolating zebrafish-specific active fractions by multi-step sample fractionation procedures. Chemical analyses of these specific fractions so far identified several candidate compounds, of which few showed higher selectivity towards zfERβ2 than hERα, hence confirming inter-species differences. This work supports recommendations for the integration of these effect-based tools in future water monitoring strategies.
Pharmaceuticals and personal care products (PPCPs) are those substances used for medical care, cosmetics, hygiene and health care purposes. Due to their globally high production and consumption rates and rapid discharge into the environment without control, they are of considerable public concern. Many of them, particularly antibiotics, analgesics, endocrine disruptors and microbial/disinfecting substances are frequently detected in wastewater treatment effluents, fresh water systems and groundwater in concentrations ranging from ng L‐1 to mg L‐1. Moreover, most of them are persistent and tend to bioaccumulate in cell tissue, being transported subsequently to vegetables, crops and drinking water sources. As such, a large group of PPCPs are recognized with their potential to impair the ecosystem and/or to induce health risks, so that they have been classified under “emerging contaminants”. The present study is a comprehensive review of the literature on the occurrence, fate and potential environmental and health risks of PPCPs in the aquatic and terrestrial environments. It also encompasses the reported cases of human health disorders or risks, although the data so far is inadequate for presenting a complete assessment. Finally, the study covers a short review of the most promising advanced technologies for their partial or ultimate elimination from wastewater treatment effluents and water. This article is protected by copyright. All rights reserved.
Pharmaceuticals and personal care products (PPCPs) include therapeutic drugs, fragrances, sunscreens, detergents, cosmetics, plasticizers, and their metabolites. Presence of these compounds at detectable levels in the environment (surface, ground and wastewater, effluents, soil, and sediment) poses a threat to living biota. Humans get exposed to these compounds via consumption of contaminated food/water and through external application. These compounds break down and get transformed into secondary compounds that have harmful effects on human health. Many of these compounds act as endocrine disrupters and target specific metabolic, molecular pathways in humans. They prove toxic and induce neurological, biochemical, and physiological defects. They act as causal agents of diseases such as cancer, diabetes, bronchitis, respiratory tract infection, teratogenic disorders, and reproductive disorders in humans. Dioxin compounds in particular affect brain development and produce developmental defects in children. Study of the mode of action of PPCPs can prove useful in finding ways of minimizing their toxicity.
The direct photolysis of estrone in solvents ranging from water to cyclohexane is reported. The photodegradation is dominated by lumiestrone, an epimer of estrone resulting from the inversion of the methyl group at carbon 13, regardless of solvent and photolysis wavelength in the range 254 – 320 nm. Solvent addition products are also observed in lesser amounts. The photodegradation rate in water is an order of magnitude slower than in non-aqueous solvents. Short wavelength excitation enhances photodegradation. Together, these results suggest complicated photophysics underlie the photochemistry with implications for the remediation of environmental estrogens.
Over the years, the persistent occurrence of superfluous endocrine-disrupting compounds (EDCs) (sub µg L−1) in water has led to serious health disorders in human and aquatic lives, as well as undermined the water quality. At present, there are no generally accepted regulatory discharge limits for the EDCs to avert their possible negative impacts. Moreover, the conventional treatment processes have reportedly failed to remove the persistent EDC pollutants, and this has led researchers to develop alternative treatment methods. Comprehensive information on the recent advances in the existing novel treatment processes and their peculiar limitations is still lacking. In this regard, the various treatment methods for the removal of EDCs are critically studied and reported in this paper. Initially, the occurrences of the EDCs and their attributed effects on humans, aquatic life, and wildlife are systematically reviewed, as well as the applied treatments. The most noticeable advances in the treatment methods include adsorption, catalytic degradation, ozonation, membrane separation, and advanced oxidation processes (AOP), as well as hybrid processes. The recent advances in the treatment technologies available for the elimination of EDCs from various water resources alongside with their associated drawbacks are discussed critically. Besides, the application of hybrid adsorption–membrane treatment using several novel nano-precursors is carefully reviewed. The operating factors influencing the EDCs’ remediations via adsorption is also briefly examined. Interestingly, research findings have indicated that some of the contemporary techniques could achieve more than 99% EDCs removal.
Emerging contaminants (ECs), a class of contaminants with low concentrations but significant harm, have received a lot of attention in recent times. ECs comprises of various chemicals that enter the environment every day. In today's modern lifestyle, we use many chemical-based products. These persist in wastewater and ultimately enter the water bodies, causing serious problems to the human and aquatic ecosystem. This is because the conventional wastewater treatment methods are inefficient in identifying and removing such contaminants. Aiming for a long-term, effective solution to this issue, Adsorption was proposed. Although several adsorbents are already present in the market, which have proved beneficial in removing such ECs, not all are affordable. This article reviews replacing costly adsorbents with agriculture-based biomass that are abundant, inexpensive, and biodegradable and possess excellent adsorption capacity. The objectives of this article is to look at adsorption as a viable treatment option for emerging pollutants, as well as sophisticated and cost-effective emerging contaminants treatment options.
Carbamazepine is a pharmaceutical used in patients with seizures and bipolar disorder, which has been found in wastewater and many water resources. This is due to the inadequate disposal of pharmaceutical waste and the lack of treatment of municipal wastewater, as is the case in Colombia. The two main hydrographic basins of Colombia are the Cauca and Magdalena rivers, which are inhabited by the endemic species Striped Catfish (Pseudoplatystoma magdaleniatum). This has become an endangered species for various reasons, including the high contamination level of these rivers. In 2019, mature adult P. magdaleniatum of both sexes were caught in the Cauca river in Colombia. This was in order to assess the concentration of vitellogenin, as a biomarker of endocrine disruption, resulting from exposure to different levels of concentration of the emerging contaminant carbamazepine for 4 months. These tests were carried out in a fish farm. A significant decrease in the vitellogenin concentration was verified in females at concentrations of 25 µg l-1 and 50 µg l-1, and in males at 50 µg l-1 of carbamazepine, with a significance level of p˂0.05. Carbamazepine could cause a negative feedback in gonadotropin secretion, acting as an estrogen mimicker that causes a decrease in the level of vitellogenin.
Background: 17α-Ethinylestradiol (EE2) is an environmental endocrine disruptor that causes serious harm to the human body, so how to effectively remove EE2 is an urgent problem that people need to solve. Herein, BiVO4 photo-catalyst was applied to the photo-catalytic degradation of EE2 and the influence of the catalyst's wettability on the degradation of EE2 was discussed.
Methods: BiVO4 photo-catalyst was prepared by hydrothermal method, and modified with different doses of 3-aminopropyltriethoxysilane (APTES) to tune its surface wettability.
Significant Findings: Through the research, it was found that adjusting the WCA of APTES-modified BiVO4 to the range of 14.0 °∼23.6 ° can obtain better photo-catalytic activity. When the Water Contact Angle (WCA) of modified BiVO4 was 17.7 ° (0.70 mL APTES), the photo-catalytic activity was the best, with the removal rate of EE2 reaching 91.27%, while unmodified BiVO4 was only 59.34%. The reaction rate constant of BiVO4 (0.70 APTES) for the photo-catalytic degradation of EE2 was 2.78 times of unmodified BiVO4. Compared to other methods, the method of improving the photo-catalytic performance by controlling the wettability of the material surface was simpler and more flexible. Therefore, it has a very broad application prospect in the efficient removal of organic pollutants.
There is growing worry that drinking water can be affected by contaminants of emerging concern (CECs), potentially threatening human health. In this study, a wide range of CECs (n = 177), including pharmaceuticals, pesticides, perfluoroalkyl substances (PFASs) and other compounds, were analysed in raw water and in drinking water collected from drinking water treatment plants (DWTPs) in Europe and Asia (n = 13). The impact of human activities was reflected in large numbers of compounds detected (n = 115) and high variation in concentrations in the raw water (range 15-7995 ng L⁻¹ for ∑177CECs). The variation was less pronounced in drinking water, with total concentration ranging from 35 to 919 ng L⁻¹. Treatment efficiency was on average 65 ± 28%, with wide variation between different DWTPs. The DWTP with the highest ∑CEC concentrations in raw water had the most efficient treatment procedure (average treatment efficiency 89%), whereas the DWTP with the lowest ∑177CEC concentration in the raw water had the lowest average treatment efficiency (2.3%). Suspect screening was performed for 500 compounds ranked high as chemicals of concern for drinking water, using a prioritisation tool (SusTool). Overall, 208 features of interest were discovered and three were confirmed with reference standards. There was co-variation between removal efficiency in DWTPs for the target compounds and the suspected features detected using suspect screening, implying that removal of known contaminants can be used to predict overall removal of potential CECs for drinking water production. Our results can be of high value for DWTPs around the globe in their planning for future treatment strategies to meet the increasing concern about human exposure to unknown CECs present in their drinking water.
RESUMO O uso de agrotóxicos na agricultura brasileira é um problema de saúde pública, dadas as contaminações no ambiente, em alimentos e as intoxicações resultantes do uso dessas substâncias. O objetivo deste artigo é investigar a distribuição espacial das áreas plantadas de lavouras e as taxas de mortalidade de alguns tipos de câncer: mama, colo do útero e próstata. Escolheram-se quatro estados brasileiros que possuem grande produção de commodities agrícolas a serem estudadas. Trata-se de um estudo ecológico de análise espacial conduzido com dados e informações do Sistema de Informação sobre Mortalidade (SIM) do Ministério da Saúde, por meio do qual elaboraram-se taxas de mortalidade para os referidos tipos de câncer, cujos óbitos tenham ocorrido entre 1996 e 2016. Há indícios de que existe correspondência entre as áreas de maior estimativa de uso de agrotóxicos Disruptores Endócrinos e o aumento das taxas de mortalidade pelos diferentes tipos de câncer.
Toxicological Effects of Veterinary Medicinal Products in Humans is the first definitive guide to discuss the adverse effects of veterinary medicinal products in humans. The chapters focus on occupational safety and consumer issues and examine the circumstances under which exposure is likely to occur. To be in context, it reviews this against the background of adverse health effects from other sources in the veterinary and farming professions. The book examines adverse drug effects reported to regulatory agencies (mainly the FDAÆs Center for Veterinary Medicine) and then considers a series of individual drugs, including antibiotics, anaesthetics and organophosphorus compounds. The chapters also discuss the fundamental aspects of regulatory issues relating to safety assessment, and examine the manner in which user safety is assessed prior to authorisation/approval and what measures can be taken after authorisation/approval in the light of findings from pharmacovigilance activities. There is growing concern over the issue of antimicrobial resistance and the contribution made by veterinary medicinal products. This too is addressed along with the significance to human health and measures that can be taken to mitigate the effects (if any) of the use of antibiotics in animals e.g. prudent use measures. The book will be an essential resource for medical practitioners in hospitals and general practice, pharmaceutical industry scientists, analysts, regulators and risk managers.
Water is a critical resource necessary for life to be sustained, and its availability should be secured, appropriated, and easily obtainable. The continual detection of endocrine-disrupting chemicals (EDCs) (ng/L or µg/L) in water and wastewater has attracted critical concerns among the regulatory authorities and general public, due to its associated public health, ecological risks, and a threat to global water quality. Presently, there is a lack of stringent discharge standards regulating the emerging multiclass contaminants to obviate its possible undesirable impacts. The conventional treatment processes have reportedly ineffectual in eliminating the persistent EDCs pollutants, necessitating the researchers to develop alternative treatment methods. Occurrences of the EDCs and the attributed effects on humans and the environment are adequately reviewed. It indicated that comprehensive information on the recent advances in the rejection of EDCs via a novel membrane and membrane bioreactor (MBR) treatment techniques are still lacking. This paper critically studies and reports on recent advances in the membrane and MBR treatment methods for removing EDCs, fouling challenges, and its mitigation strategies. The removal mechanisms and the operating factors influencing the EDCs remediation were also examined. Membranes and MBR approaches have proven successful and viable to eliminate various EDCs contaminants.
The decoration of TiO2-based junctions on carbon fibers has been well-developed as weavable photocatalysts for degrading hazardous pharmaceutical pollutants, but their practical application is still constrained by unsatisfactory adsorption and photodegradation performances, resulting from low surface area/porosity and photoactivity. Herein, we propose the growth of MIL-101(Fe) nanodots with small size of 5-10 nm as a porous co-photocatalyst to decorate TiO2 nanorods on CFs. CFs/TiO2/MIL-101(Fe) bundles display a wide absorption with an edge (∼600 nm). Subsequently, CFs/TiO2/MIL-101(Fe) bundles are weaved into a macroscopical cloth (0.2 g, 4×4 cm²). CFs/TiO2/MIL-101(Fe) cloth can efficiently adsorb 46.9% 17β-estradiol (E2) and 40.2% tetracycline hydrochloride (TC) after 60 min in the dark, with obvious improvement (5.4∼8.4 times) compared with that by CFs/TiO2 cloth (8.7% E2 and 4.8% TC). Importantly, under visible light irradiation, CFs/TiO2/MIL-101(Fe) cloth can remove 87.4% E2 and 94.2% TC in 60 min, which is 6∼13.1 times compared with that by CFs/TiO2 cloth (14.6% E2 and 7.2% TC), resulting from the high adsorption and three-component synergistic photocatalytic activity. Therefore, the construction of semiconductor-MOF nanojunctions on CFs provides a general strategy to develop novel weavable photocatalysts for eliminating pharmaceutical pollutants.
The need to implement an agricultural system taking into account sustainable development has fostered many initiatives to develop alternative methods in order to reduce the use of chemical synthetic pesticides for plant protection. Among these alternatives, the use of Biocontrol Agents (BCAs) or biopesticides has aroused increasing interest because of their ecological advantages. Their commercialization now increases but the part they occupy in Plant Protection Products (PPP) market is still marginal. After defining what are the BCAs (biopesticide) products, this chapter analyses the factors that encourage or hamper this development and also considers the room of BCAs (biopesticides) and the trends in the global PPP market.
Advancement in technology has led to the development of highly sensitive, accurate, efficient and robust analytical instrumentals, but without sample preparation, these state-of-the-art instruments are not capable of analyzing samples. Liquid-liquid extraction (LLE) was a widely used sample preparation technique, but setbacks such as long extraction periods, consumption of toxic solvents in large amounts and low efficiency led to its miniaturization, which is commonly termed liquid phase microextraction (LPME). LPME methods such as single drop microextraction, dispersive liquid-liquid microextraction and solidified floating organic drop microextraction overcome the limitations of the conventional LLE, and recent researches have focused on greener microextraction strategies based on extractants like ionic liquids and switchable polarity solvents. This review is aimed at presenting readers with a comprehensive overview of liquid phase microextraction methods, recent developments and novel approaches that are used to extract/preconcentrate endocrine disruptive compounds from food matrices for determination by different instrumentations.
The natural estrogen 17β-estradiol (17β-E2) is a major endocrine disruptor. Accordingly, due to their frequent presence in global surface waters, prolonged exposure to estrogen-contaminated water may disrupt sexual development in animals. It has adverse effects on wildlife and humans. To date, the most effective strategy for estrogen removal from the environment is biodegradation using microorganisms. To this end, we isolated a strain of Lysinibacillus sphaericus, namely DH-B01, from a contraceptive factory in Beijing. The experimental results revealed that the bacterium has a high capacity to degrade estrogen, with a 17β-E2 degradation rate of about 97%, and produces the secondary metabolite estrone. In addition, a series of genes involved in steroid metabolism and stress response in L. sphaericus sp. DH-B01 were predicted, and several key genes with high similarity to those of other strains were subjected to sequence alignment to find their conserved regions. This is the first study of the ability of L. sphaericus strains to degrade estrogens and the degradation mechanism involved. This work advances the genomic study of estrogen-degrading strains and the study of bacterial estrogen degradation mechanisms. In this paper, a novel bacterial strain capable of degrading 17β-E2 was studied. L. sphaericus sp. DH-B01 can effectively degrade 17β-E2. During the degradation process, 17β-E2 can be gradually metabolized to a substance without estrogen activity. By analyzing the enzymatic reactions in the metabolic process, we found genes with high similarity to reported 17β-HSD. L. sphaericus sp. DH-B01 was found to degrade 17β-E2. There are many types of bacteria that are currently being studied for the degradation of estrogen, but L. sphaericus sp. DH-B01 is the only strain of L. sphaericus that has been shown to degrade estrogen. This work advances the genomic study of estrogen-degrading bacterial strains and the study of bacterial estrogen degradation mechanisms. Additionally, it explores the correlation between different L. sphaericus strains. The differences play an important role and further enrich the functionality and diversity of L. sphaericus strains. In subsequent studies, the specificity of L. sphaericus sp. DH-B01 can be applied to different environments for future environmental restoration.
Paper mill effluents are discharged into Elevenmile Creek at Cantonment, Escambia County, Florida. The total population of mosquitofish, Gambusia affinis holbrooki, inhabiting the stream below the effluent discharge exhibits abnormal sexuality. All females are strongly masculinized, displaying both physical secondary sex characters and reproductive behavior of males. Males exhibit precocious development of physical secondary sex characters and reproductive behavior. Elevenmile Cr. above the paper-mill effluent, as well as tributaries to this creek, all contain Gambusia with normal secondary sex characters. This evidence strongly suggests that some yet unidentified chemical or combination of chemicals associated with the paper-mill effluent exerts a strong androgenic effect upon this population. This constitutes the first report of possible environmentally-induced masculinization involving a total natural population of vertebrates.
A recent study by the Toxic Substances Hydrology Program of the U.S. Geological Survey (USGS) shows that a broad range of chemicals found in residential, industrial, and agricultural wastewaters commonly occurs in mixtures at low concentrations downstream from areas of intense urbanization and animal production. The chemicals include human and veterinary drugs (including antibiotics), natural and synthetic hormones, detergent metabolites, plasticizers, insecticides, and fire retardants. One or more of these chemicals were found in 80 percent of the streams sampled. Half of the streams contained 7 or more of these chemicals, and about one-third of the streams contained 10 or more of these chemicals. This study is the first national-scale examination of these organic wastewater contaminants in streams and supports the USGS mission to assess the quantity and quality of the Nation's water resources. A more complete analysis of these and other emerging water-quality issues is ongoing.
Keywords:
pharmaceuticals;
hormones;
other wastewater contaminants;
steroids;
nonprescription drugs;
veterinary pharmaceuticals
Feral mosquitofish living in undiluted treated municipal sewage in Queensland, Australia, were examined for morphologic abnormalities indicative of reproductive dysfunction. Male and female mosquitofish were captured at two sites receiving undiluted treated sewage and compared with those captured at a reference site. Several morphologic end points were examined, including length of the fourth and sixth anal fin rays and gonadal histology. Both male and female mosquitofish at one site exhibited minor elongation of the fourth anal fin ray consistent with exposure to androgenic stimulation, although the spatial extent of the effect was limited and not significant at other sites further downstream. No incidences of intersex were found. These findings suggest that the level of treatment of domestic sewage at the two sewage treatment plants assessed is adequate to prevent reproductive abnormalities in exposed mosquitofish populations.
Estrogen-responsive proliferation in the MCF-7 cell line was used as a bioassay for detection of dietary estrogens. The bioassay procedure was adapted to screen for estrogenic activity in feedstuffs that have been associated with hyperestrogenism in livestock. Methanolic feed extracts were added to the cell culture medium at microliter/ml concentrations for 4 days, after which the cell proliferation response was measured as DNA content. The half-maximal response for estradiol occurred at 2 pM, or 0.54 pg/ml. For zearalenone, a weaker estrogen, the half-maximal response occurred at approximately 200 pM, or 64 pg/ml. The bioassay was calibrated against a number of known estrogens (estradiol, diethylstilbestrol, zearalenone, zearalanol [cattle implant], beta-zearalenol, zearalane), including the naturally occurring phytoestrogens (formononetin, genistein, daidzein, biochanin A, and coumestrol). The estrogenic activity of feed samples was expressed as equivalents of zearalenone (ppm zearalenone) that would have to be present to equally stimulate proliferation of the MCF-7 cells. The sensitivity of the bioassay was 0.05-0.1 ppm equivalents of zearalenone in feed, well below the threshold level associated with reproductive problems. The feed additive melengestrol acetate (MGA) showed no estrogenic activity in this assay. Estrogenic activity of feed extracts was confirmed by competitive inhibition with the antiestrogens tamoxifen or LY156758 (keoxifene) to show that stimulation of growth by feed extracts was through an estrogenic mechanism. Confirmation of known estrogens was by tandem mass spectroscopy. The assay is a sensitive and reliable screening procedure for detecting estrogenic activity in feedstuffs.
The relation between spontaneous abortion (n = 5010), stillbirth without congenital defect (n = 210), and working conditions was analysed in 22,613 previous pregnancies of 56,067 women interviewed, 1982-4, immediately after termination of their most recent (current) pregnancy. The 22,613 previous pregnancies were those in which at time of conception the women were employed 30 or more hours a week. Ratios of observed (O) to expected (E) fetal deaths after allowance by logistic regression for seven non-occupational confounding variables were calculated at four stages of pregnancy in 60 occupational groups and six main sectors for women whose work entailed various physical demands, environmental conditions, and exposure to chemicals. The O/E ratios for abortion were raised in the sales sector (1.13, p less than 0.05) and services sector (1.11, p less than 0.01) and for stillbirth in the sales sector (1.50, p less than 0.1). Substantially increased O/E ratios for late but not early abortion were found in operating room nurses (2.92, p less than 0.05), radiology technicians (3.82, p less than 0.01), and employees in agriculture and horticulture (2.40, p less than 0.05); in all categories the O/E ratio for stillbirth were also raised but only significantly (5.55, p less than 0.01) in the latter group. The O/E ratio for stillbirth was also raised in leather manufacture (3.09, p less than 0.01). In both individual and grouped analysis (the latter undertaken to minimise the possible effect of recall bias) significantly increased O/E ratios for abortion were found in women exposed to various high levels of physical stress, particularly weight lifting, other physical effort, and standing (p less than 0.01). Increased ratios for stillbirth at this level of significance (p less than 0.01) were found for other physical effort and vibration. Noteworthy chemical exposure was identified only in the health, services, and manufacturing sectors; the O/E ratio for stillbirth approached two in women exposed to solvents, almost all in manufacturing (p less than 0.01). In the latter sector exposed to solvents was also associated with an approximately 20% increase in abortion ratio at similar probability level.
Sewage, a complex mixture of organic and inorganic chemicals, is considered to be a major source of environmental pollution. A random screen of 20 organic man-made chemicals present in liquid effluents revealed that half appeared able to interact with the estradiol receptor. This was demonstrated by their ability to inhibit binding of 17 beta-estradiol to the fish estrogen receptor. Further studies, using mammalian estrogen screens in vitro, revealed that the two phthalate esters butylbenzyl phthalate (BBP) and di-n-butylphthalate (DBP) and a food antioxidant, butylated hydroxyanisole (BHA) were estrogenic; however, they were all less estrogenic than the environmental estrogen octylphenol. Phthalate esters, used in the production of various plastics (including PVC), are among the most common industrial chemicals. Their ubiquity in the environment and tendency to bioconcentrate in animal fat are well known. Neither BBP nor DBP were able to act as antagonists, indicating that, in the presence of endogenous estrogens, their overall effect would be cumulative. Recently, it has been suggested that environmental estrogens may be etiological agents in several human diseases, including disorders of the male reproductive tract and breast and testicular cancers. The current finding that some phthalate compounds and some food additives are weakly estrogenic in vitro, needs to be supported by further studies on their effects in vivo before any conclusions can be made regarding their possible role in the development of these conditions.
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The increase in the number of reports of abnormalities in male sex development in wildlife and humans coincided with the introduction of 'oestrogenic' chemicals such as DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) into the environment. Although these phenotypic alterations are thought to be mediated by the oestrogen receptor, they are also consistent with inhibition of androgen receptor-mediated events. Here we report that the major and persistent DDT metabolite, p,p'-DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene), has little ability to bind the oestrogen receptor, but inhibits androgen binding to the androgen receptor, androgen-induced transcriptional activity, and androgen action in developing, pubertal and adult male rats. The results suggest that abnormalities in male sex development induced by p,p'-DDE and related environmental chemicals may be mediated at the level of the androgen receptor.
Estrogens are defined by their ability to induce the proliferation of cells of the female genital tract. The wide chemical diversity of estrogenic compounds precludes an accurate prediction of estrogenic activity on the basis of chemical structure. Rodent bioassays are not suited for the large-scale screening of chemicals before their release into the environment because of their cost, complexity, and ethical concerns. The E-SCREEN assay was developed to assess the estrogenicity of environmental chemicals using the proliferative effect of estrogens on their target cells as an end point. This quantitative assay compares the cell number achieved by similar inocula of MCF-7 cells in the absence of estrogens (negative control) and in the presence of 17 beta-estradiol (positive control) and a range of concentrations of chemicals suspected to be estrogenic. Among the compounds tested, several "new" estrogens were found; alkylphenols, phthalates, some PCB congeners and hydroxylated PCBs, and the insecticides dieldrin, endosulfan, and toxaphene were estrogenic by the E-SCREEN assay. In addition, these compounds competed with estradiol for binding to the estrogen receptor and increased the levels of progesterone receptor and pS2 in MCF-7 cells, as expected from estrogen mimics. Recombinant human growth factors (bFGF, EGF, IGF-1) and insulin did not increase in cell yields. The aims of the work summarized in this paper were a) to validate the E-SCREEN assay; b) to screen a variety of chemicals present in the environment to identify those that may be causing reproductive effects in wildlife and humans; c) to assess whether environmental estrogens may act cumulatively; and finally d) to discuss the reliability of this and other assays to screen chemicals for their estrogenicity before they are released into the environment.
Male reproductive health has deteriorated in many countries during the last few decades. In the 1990s, declining semen quality has been reported from Belgium, Denmark, France, and Great Britain. The incidence of testicular cancer has increased during the same time incidences of hypospadias and cryptorchidism also appear to be increasing. Similar reproductive problems occur in many wildlife species. There are marked geographic differences in the prevalence of male reproductive disorders. While the reasons for these differences are currently unknown, both clinical and laboratory research suggest that the adverse changes may be inter-related and have a common origin in fetal life or childhood. Exposure of the male fetus to supranormal levels of estrogens, such as diethlylstilbestrol, can result in the above-mentioned reproductive defects. The growing number of reports demonstrating that common environmental contaminants and natural factors possess estrogenic activity presents the working hypothesis that the adverse trends in male reproductive health may be, at least in part, associated with exposure to estrogenic or other hormonally active (e.g., antiandrogenic) environmental chemicals during fetal and childhood development. An extensive research program is needed to understand the extent of the problem, its underlying etiology, and the development of a strategy for prevention and intervention.
To analyse the risk of stillbirth from 12 residential and occupational maternal exposures during pregnancy.
Stillbirths and neonatal deaths in 1984 within 24 hours of birth from 10 California counties were identified from death certificates. Controls were randomly selected from live births born in 1984 and frequency matched to cases by maternal age and county. Data sources included vital statistics and a self-administered postal questionnaire. Logistic regression and proportional hazards modelling were performed; the proportional hazards considered the truncated opportunity for exposure among cases. Special focus was given to two cause of deaths groups: congenital anomalies (12% of deaths) and complications of the placenta, cord, and membranes (37% of deaths).
Occupational exposure to pesticides during the first two months of gestation was positively associated with stillbirths due to congenital anomalies (odds ratio (OR) 2.4, 95% confidence interval (95% CI) 1.0 to 5.9), and during the first and second trimesters with stillbirths due to all causes of death (risk ratios (RR) 1.3-1.4, 95% CI 1.0 to 1.7) and stillbirths due to complications of the placenta, cord, and membranes (RR 1.6-1.7, 95% CI 1.1 to 2.3). Occupational exposure to video display terminals in the third trimester was found to have a modest inverse association with stillbirths (RR 0.7, 95% CI 0.6, 0.9). Home pesticide exposure was positively associated with stillbirths due to congenital anomalies (OR 1.7, 95% CI 1.0 to 2.9).
Occupational exposure to pesticides, especially during early pregnancy, had a clear positive association with stillbirths regardless of cause of death. Methodologically, this study of stillbirths is unique in its analysis of specific causes of death and use of time specific exposure windows.
The in utero effects of diethylstilbestrol on the human male genital tract are reported in our followup study of male offspring of mothers treated with diethylstilbestrol. Anatomical and functional abnormalities were significantly greater in male patients exposed to diethylstilbestrol compared to male controls whose mothers were all participants in a prospective, randomized double-blind study on the effects of diethylstilbestrol on pregnancy at our hospital during the early 1950s.
DES is the most carefully scrutinized EDC and its history provides valuable insights into the current evaluation of less well-studied EDCs. This review summarizes the health effects of prenatal exposure to diethylstilbestrol (DES) and emphasizes the role of DES as the first endocrine disrupting chemical (EDC). Vaginal clear cell adenocarcinoma (CCAC), the most severe consequence of prenatal exposure to DES, affected only 0.1% of exposed females, while the far more prevalent teratogenic and reproductive effects of DES were only discovered when DES daughter were screened for CCAC. Initial studies, conducted before most DES daughters had tried to conceive, examined vaginal cancer and vaginal, cervical and uterine abnormalities. Subsequently, several controlled studies demonstrated the increased risk of adverse reproductive outcomes in DES daughters. While most DES daughters can eventually experience a live birth, this is less likely in women with genital tract abnormalities, in whom there is a two-thirds chance that each pregnancy will be unsuccessful. In DES sons, who have been far less studied, results suggest male reproductive toxicity, but are less consistent. The importance of dose and gestational age at initial exposure are discussed, and the implications of DES findings for the evaluation of risks from current EDCs emphasized.
Sexually mature male common carp (Cyprinus carpio) were exposed for a 3-month period to sublethal concentrations of 4-tert-pentylphenol (TPP) and to 17 beta-estradiol (E2) during spermatogenesis. This was part of a broad research programme investigating the effects of TPP on the life stages of the carp which might prove susceptible to endocrine disruption. Exposure of adult male carp to the pseudo-estrogen TPP, or to E2 during sexual maturation, led to elevated plasma levels of vitellogenin (P < 0.001), a typically female protein and to the inhibition of the spermatogenesis. The histological examination of the testes showed the progressive disappearance of spermatozoa and spermatogenic cysts, and a higher incidence of pathological alterations with time at all TPP and E2 concentrations (e.g. fibrosis, vacuolation and atrophy of the germinal epithelium). A reduced diameter of the seminiferous lobules (P < 0.001) was measured in fish testes exposed to all TPP concentrations for 3 months and in some TPP exposures, after 1 and 2 months. After a 3-month exposure, the spermatocrit values of fish exposed to the highest TPP concentration were significantly lower than those of the control (P < 0.01), whilst those fish exposed to the highest E2 concentration did not produce any milt. The occurrence of early ovo-testes in some fish with completely regressed testes suggests that oogenesis may proceed in testes which have first been inhibited (demasculinised) following estrogenic stimulus.
Japanese medaka were exposed to environmentally-relevant concentrations of environmental estrogens: nonylphenol (NP, 0.5, 0.8 and 1.9 μg l−1), methoxychlor (MXC, 0.2, 0.6 and 2.3 μg l−1) and estradiol (E2, 0.01, 0.12 and 1.66 μg l−1). Exposure occurred throughout the first month following hatch. E2 survival ratios following the exposure period were significantly altered compared to control groups. Following a month period of `growout' in dilution water only, sex ratios were measured and reproductive capabilities assessed. No alteration in sex ratios was observed following treatment with NP or MXC. All three concentrations of E2 were sufficient to produce exclusively female populations. There was no depreciation in reproductive capability in the NP or MXC-treated fish as measured by fecundity, viability of eggs, or hatchability of eggs. E2-treated female fish had a lower fecundity in the highest concentration.
Oestrogenic isoflavone compounds in clover continue to cause reproductive losses in sheep in Western Australia. The phyto-oestrogens can cause two infertility syndromes in sheep, one of which resolves after the phyto-oestrogen is removed, while the other form of infertility is permanent and increases in severity with continued exposure to phyto-oestrogen. There is often a poor association between the extent of exposure to phyto-oestrogens and the severity of the infertility, but the reason for this is not fully known. The balance between epidemiological and laboratory-based research over the past 50 years has not always been optimal, delaying the application of measures to control the problem. To a large extent, this imbalance arose because numerous differences between species in their response to phytooestrogens were not appreciated.
A fractionation system, combined with an in vitro assay for detecting estrogenic activity, was developed in order to isolate and identify the major estrogenic chemicals present in seven sewage-treatment works (STW) effluents, receiving primarily domestic effluent, discharging into British rivers. Three sterols were isolated from estrogenic fractions of sewage extracts; these were the natural hormones 17β-estradiol and estrone and the synthetic hormone 17α-ethynylestradiol. 17β-Estradiol and estrone were present in all the effluents at measured concentra tions ranging from 1 ng/L to almost 50 and 80 ng/L, respectively. The concentration of 17α-ethynylestradiol was generally below the limit of detection but was positively identified in three of the effluent samples at concentrations ranging from 0.2 to 7.0 ng/L. These data suggest that natural and synthetic hormones may be responsible for the observed induction of vitellogenin synthesis in male fish placed downstream of effluent discharges from STWs that receive mainly domestic inputs.
This study evaluates a recent report indicating that androstenedione (4-androsten-3, 17-dione) contributes to the andro-genicity of water downstream of a pulp and paper mill discharge on the Fenholloway River (FL, USA). Extraction and concentration of Fenholloway water with C18 solid-phase extraction columns followed by reverse-phase high-pressure liquid chromatography resulted in clearly defined fractions with in vitro androgenic activity in CV-1 cells that had been transiently cotransfected with human androgen receptor and reporter gene constructs. However, we were unable to detect androstenedione in the active fractions by gas chromatography/mass spectrometry. Mass spectrometry analyses of deionized and Fenholloway River water samples that had been spiked with androstenedione, then extracted and fractionated, revealed that the androgen was found only in inactive fractions. We conclude that, although androstenedione was present at easily detectable concentrations in the river water (>100 ng/L), this compound is not associated with androgenic activity of water from the site.
Although a relatively new area of environmental research, the field of endocrine disruption has grown very rapidly, and currently many hundreds, perhaps even a few thousand, papers are published annually on the many different aspects covered by the field. As far as endocrine disruption in wildlife is concerned, most attention has been focused on aquatic organisms, for two reasons. Firstly, the aquatic environment receives most of the pollutants intentionally released into the environment, through effluents from wastewater treatment plants, and secondly because many of the best documented examples of endocrine disruption in wildlife are of partially or completely aquatic species. These two reasons are probably not unconnected, of course. Hence, aquatic organisms can receive continuous exposure to endocrine-disrupting chemicals throughout their lives, albeit usually to low concentrations of these chemicals. Analysis of effluents has identified many of the endocrine-disrupting chemicals present, and shown that these are both natural and man-made, and vary greatly in potency. Most attention has been directed to identifying the main estrogenic chemicals, because many of the effects reported in wildlife appear to be a consequence of ‘feminization’ of males. However, chemical analysis of effluents has also demonstrated that chemicals with other types of endocrine activity are present, such as androgens, anti-androgens, progestagens, etc. The effects (if any, of course) of such chemicals on aquatic organisms are unknown, and largely uninvestigated, presently. Much of the biological research has centred on the effects of estrogenic chemicals, especially to fish. These effects, such as elevated vitellogenin concentrations and intersexuality, have to date been studied almost exclusively at the level of the individual, and hence whether endocrine-disrupting chemicals cause population-level consequences is largely unknown (the undeniable effects of TBT on molluscs, leading to local extinctions, being the exception). It is my opinion that rather too much of the recent research has not advanced our understanding of endocrine disruption a great deal, and we are probably not much further forward now than we were five years or so ago. It is surely time to tackle some of the outstanding, unresolved issues, such as the impact of endocrine disruption at the population level, and the issue of how organisms respond when exposed to complex mixtures of endocrine active chemicals. Such research will not be easy, and will require multidisciplinary teams, including people with expertise in areas not yet involved in the field of endocrine disruption, such as mathematical modellers. However, until such research is done, it will not be possible to decide how important an issue endocrine disruption is to wildlife, and how that importance compares to the other factors adversely affecting wildlife, such as habitat loss, climate change, and the introduction of exotic species and novel diseases.Endokrine Disruptoren in der Umwelt: eine ÜbersichtDas Thema endokrine Disruption ist im Umweltbereich ein noch relativ junges, schnell wachsendes Forschungsgebiet. Mittlerweile erscheinen jährlich viele hundert, vielleicht sogar mehrere tausend Publikationen zu seinen diversen Aspekten. Soweit es die Tierwelt betrifft, konzentriert sich die Aufmerksamkeit hauptsächlich auf aquatische Organismen. Das hat zwei Gründe: Erstens gelangt der Hauptanteil der in die Umwelt eingetragenen endokrinen Disruptoren in das Kompartiment Wasser – über Kläranlagenabläufe – und zweitens betreffen die am besten dokumentierten Beispiele endokriner Disruption in der Tierwelt im Wasser lebende Arten. Beide Phänomene sind nicht unabhängig voneinander zu sehen. Aquatische Organismen sind unter Umständen ihr ganzes Leben lang kontinuierlich endokrin wirksamen Substanzen ausgesetzt – wenn auch in geringen Konzentrationen. Viele der endokrin wirksamen Substanzen im Abwasser wurden mittlerweile identifiziert, es handelt sich sowohl um natürliche als auch um synthetische Stoffe sehr unterschiedlicher Potenz. Als vordringlich wurde empfunden, die wichtigsten östrogen wirksamen Chemikalien zu identifizieren, da die meisten aus der Tierwelt berichteten Effekte Folge einer Verweiblichung der männlichen Tiere waren. Die Untersuchungen an Abläufen ergaben allerdings, dass auch Chemikalien mit anders gelagerter endokriner Wirkung darin vorkommen, wie Androgene, Anti-Androgene, Progestagene usw. Die Wirkung dieser Substanzen auf aquatische Organismen ist unbekannt und derzeit auch noch relativ unerforscht. Die meisten Forschungsaktivitäten konzentrieren sich auf die Auswirkungen östrogen wirksamer Substanzen, vor allem auf Fische. Diese Wirkungen, wie z. B. erhöhte Vitellogenin-Konzentration und Intersexualität, wurden fast ausschließlich an einzelnen Individuen untersucht. Es ist weitgehend unbekannt, inwieweit endokrine Disruptoren sich auf der Populationsebene auswirken. (Eine Ausnahme stellt die unbestreitbare Beeinträchtigung von Mollusken durch Tributylzinn dar, die lokal zur Auslöschung ganzer Populationen führte.) Viele der bisherigen Forschungsaktivitäten haben unser Verständnis endokriner Disruption nicht wesentlich weitergebracht, und zum Teil sind wir immer noch so weit wie vor fünf Jahren. Es wird Zeit, noch ungelöste Fragen anzugehen, wie z. B., welche Auswirkungen endokrine Disruption auf der Populations ebene hat, und die Frage, wie Organismen auf komplexe Mischungen endokrin aktiver Substanzen reagieren. Dazu bedarf es interdisziplinärer Forscherteams und Expertise auch aus anderen Arbeitsrichtungen, wie z. B. der mathematischen Modellierung. Ohne diese weitergehende Forschung ist zu nicht zu entscheiden, welche Relevanz das Thema endokrine Disruption für die Tierwelt hat und als wie wichtig es im Vergleich mit anderen, die Tierwelt beeinträchtigenden Faktoren zu bewerten ist, wie z. B. der Verlust von Lebensräumen, Klimaänderungen sowie die Einschleppung von Neozoen und neuen Krankheiten.
A number of chemicals present in the environment have been shown to mimic or antagonize the actions of steroid hormones, an issue often described as "endocrine disruption/modulation". There is very little evidence, however, to support the hypothesis that exposure to endocrine-disrupting chemicals is a global environmental health problem. In this paper, we demonstrate a high incidence of intersexuality in wild populations of riverine fish (roach; Rutilus rutilus) throughout the United Kingdom. These reproductive disturbances are consistent with exposure to hormonally active substances and are associated with discharges from sewage treatment works that are known to contain estrogenic chemicals. This is the first documented example of a widespread sexual disruption in wild populations of any vertebrate and indicates that reproductive and developmental effects do result from exposure to ambient levels of chemicals present in typical British rivers.
The effects of chronic exposure to simazine, an s-triazine herbicide, on the cladoceranDaphnia pulex were evaluated under laboratory conditions. The daphnids were exposed to simazine concentrations corresponding to previously calculated 48-hr LC5 and LC20 values and the effects on survival, growth, reproduction, and behavior were monitored daily for 26 days. Survival ofD. pulex in 20 mg/L simazine averaged 9.61.7 days. Most mortality in 4 mg/L occurred between days 21 and 25, and 65% of the daphnids were dead by day 25. Simazine interfered with molting, and growth was reduced in both concentrations tested. Reproductive maturation was delayed by about one molt cycle (3 days at 20C) inD. pulex exposed to 4 mg/L simazine and was prevented in daphnids exposed to 20 mg/L. Numbers of live young and broods produced by daphnids in 4 mg/L were significantly lower than those produced by controls.
In recent years, a hierarchy of techniques has become available for detecting chemicals which may cause endocrine disruption in the aquatic environment. The molecular structure of a chemical provides a first indication about estrogenic activity, i.e. their likelihood of interfering with the female hormone receptor. In vitro competitive binding assays for this receptor and specific cell cultures are also used to demonstrate an estrogenic response, but this does not adequately indicate whether the substance will cause adverse reproductive effects in an entire organism. An elevated level of vitellogenin, a typical female lipoprotein in the plasma of male fish is an in vivo estrogen-mediated response. However, its direct relationship to reproductive developmental effects is as yet unclear. The present study aims at investigating this relationship for assessing endocrine disruption in fish exposed to an estrogenic substance during relevant life stages. A monosex population of male carp, Cyprinus carpio, was exposed to 4-tert-pentylphenol (TPP) and to 17β-estradiol as a positive control during the period of sexual differentiation, starting at 50 days post hatch. The fish were sampled every 10 days for the histological examination of the development of the testes, i.e. the formation of the reproductive tract, the multiplication and subsequent meiosis of the primordial germ cells, and gametogenesis in the early gonad. At the end of the experiment, blood was extracted for the quantification of vitellogenin by radioimmunoassays in the plasma. The average number of primordial germ cells (PGCs) per gonadal section was significantly reduced (P<0.001) at all sampling periods in the testes of carp exposed to 17β-estradiol (positive control). The PGCs had commenced oogenesis after 50 days exposure and developed into oocytes as in a `normal' ovary. The number of PGCs in the testes of the carp exposed to TPP was reduced in a dose dependent manner. Spermatogenesis was severely inhibited in the testes of the TPP-exposed carp, where, few oocytes were ever observed. 20 days exposure to 17β-estradiol were sufficient to induce the formation of an oviduct instead of a male vas deferens, whereas this occurred after 30 days in TPP-exposed carp. A dose effect relationship with TPP was established and the EC50 calculated (63 μg TPP l−1). Vitellogenin levels were significantly elevated in the plasma of the carp exposed to both 17β-estradiol concentrations, but only at the highest 4-tert-pentylphenol concentration (256 μg TPP l−1, P<0.05). At the end of the exposure, the no observed effect concentration for the oviduct formation was <36 μg TPP l−1 and that for increased levels of vitellogenin was between 90 and 256 μg TPP l−1.
The objectives of this research were: (1) to assess the effects of waterborne 17β-estradiol [E2; (17β)-estra-1,3,5(10)-triene-3,17-diol; CAS RN 50-28-2] on the reproduction of fathead minnows (Pimephales promelas) as a benchmark to which xeno-estrogens can be compared, and (2) to correlate the effects on reproductive function with plasma vitellogenin expression, measured as alkaline-labile phosphorous. Histopathological changes were also noted but are reported elsewhere. Duplicate groups of six fish (3 male and 3 female) were exposed to waterborne E2 at nominal concentrations of 10, 1, and 0.1 nM (2724, 272.4, and 27.24 ng l−1) administered via a flow-through proportional diluter apparatus for 19 days. An ethanol carrier solvent was used at a final tank concentration of 1 ppm v/v in the treated tanks and in the solvent control tanks; the latter did not receive E2. Duplicate control tanks received neither ethanol nor E2. Dissolved E2 concentrations, measured throughout the exposure period using an ELISA, averaged 79% of nominal concentrations in the treated tanks. ELISA-detectable concentrations of E2 were found in all tanks (ranging from 3.5 to 15 ng E2 l−1), including the control and solvent control tanks, which indicated that fish in the untreated tanks may have been the source of some E2. The EC50 (concentration expected to cause 50% effect), based on measured E2 concentrations, for inhibition of egg production was 120 ng E2 l−1 (log10 EC50=2.08±1.22, ±S.E.). The EC50 for induction of vitellogenin (measured as plasma alkaline-labile phosphate) in males was 251 ng E2 l−1 (log10 EC50=2.40±0.33, ±S.E.). No vitellogenin induction plateau was observed in females, therefore no EC50 could be calculated. Egg production, expressed as eggs laid per female, was significantly correlated with plasma vitellogenin in both males (linear r2=0.46, P<0.03) and females (linear r2=0.81, P<0.0004), though the relationship was stronger with female plasma vitellogenin expression than with males. The primary effect of E2 exposure on female fathead minnows appeared to be alteration of the timing of recrudescence including vitellogenin production. Spawning was inhibited in a way that indicated that exposure to waterborne E2 may have `reset' the cycle of recrudescence toward the beginning of the oogenic cycle. Vitellogenin induction in male fathead minnows was strongly correlated with E2 exposure, but less so with egg production. The results of this experiment link a biochemical indicator of waterborne estrogen exposure, vitellogenin, with a reproductive performance indicator, egg production, an important parameter affecting fish populations in the environment.
Alkylphenol-polyethoxylates (APnEO, n = 1–40) are a major group of surfactants and are normally present in raw sewage. Many of the products of the biodegradation of these compounds are both persistent and present in substantial quantities in effluent and in river water. We report here on the use of an in vitro bioassay to determine the oestrogenic potencies of these compounds to fish. The bioassay is based on the fact that the synthesis of vitellogenin by hepatocytes is oestrogen dependent. Of the compounds tested, 4-nonylphenol, 4-tert-octylphenol, 4-tert-butylphenol, 4-nonylphenol-diethoxylate, Tergitol-NP9, and 4-nonylphenoxycarboxylic acid were all weakly oestrogenic, with potencies between about 1 × 10−4 to 1 × 10−6 the activity of 17β-oestradiol The oestrogenic activity observed appeared to be confined to para or 4 substituted compounds, because 2-tert-butylphenol and 3-tert-butylphenol were inactive. The polyethoxylate compounds became less oestrogenic with increasing lengh of the ethoxy chain. Thus cells exposed to Tergitol NP40EO (with a chain length of 40) did not secrete vitellogenin. Simultaneous exposure of the hepatocytes to Tamoxifen (an oestrogen antagonist) and effective doses of representative compounds caused an inhibition of the oestrogenic effect in all cases, suggesting that the action of these compounds is mediated by the oestradiol receptor.
It is becoming evident that an increasing number of widely used industrial and agricultural chemicals are estrogenic. The biodegradation products of a major group of nonionic surfactants, the alkylphenol polyethoxylates, are one such group. Some of these chemicals are widespread aquatic pollutants, and bioconcentrate in aquatic biota. Exposure of male rainbow trout (Oncorhynchus mykiss) to four different alkylphenolic chemicals caused synthesis of vitellogenin, a process normally dependent on endogenous estrogens, and a concomitant inhibition of testicular growth. The magnitude of these estrogenic effects was dependent on the estrogenic potency of the chemical, the stage of reproductive development of the fish, and the concentration of the chemical in the water. These results support the contention that exposure of wildlife to environmentally persistent estrogenic chemicals can result in deleterious reproductive consequences.