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This article explains the history, from 1600 BC to 2008, of materials that are today termed 'plastics'. It includes production volumes and current consumption patterns of five main commodity plastics: polypropylene, polyethylene, polyvinyl chloride, polystyrene and polyethylene terephthalate. The use of additives to modify the properties of these plastics and any associated safety, in use, issues for the resulting polymeric materials are described. A comparison is made with the thermal and barrier properties of other materials to demonstrate the versatility of plastics. Societal benefits for health, safety, energy saving and material conservation are described, and the particular advantages of plastics in society are outlined. Concerns relating to littering and trends in recycling of plastics are also described. Finally, we give predictions for some of the potential applications of plastic over the next 20 years.
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... Nhựa được biết đến lần đầu tiên vào khoảng 1600 năm trước Công nguyên và nhựa hiện đại thực sự phát triển trong 50 năm đầu của thế kỷ [1,2]. Thành công của công nghệ tổng hợp nhựa cùng các thuộc tính ưu việt với chi phí thấp đã thúc đẩy tổng sản lượng nhựa hàng năm trên toàn thế giới từ 245 triệu tấn vào năm 2008 tăng lên 322 triệu tấn vào năm 2015 [4]. Sau hơn 100 năm xuất hiện, nhựa phế thải đang trở thành mối nguy hại lớn, với những hậu quả nghiêm trọng tác động đến môi trường, hệ sinh thái và trên hết là sức khỏe con người [4]. ...
... Thành công của công nghệ tổng hợp nhựa cùng các thuộc tính ưu việt với chi phí thấp đã thúc đẩy tổng sản lượng nhựa hàng năm trên toàn thế giới từ 245 triệu tấn vào năm 2008 tăng lên 322 triệu tấn vào năm 2015 [4]. Sau hơn 100 năm xuất hiện, nhựa phế thải đang trở thành mối nguy hại lớn, với những hậu quả nghiêm trọng tác động đến môi trường, hệ sinh thái và trên hết là sức khỏe con người [4]. ...
... Nghiên cứu cũng khẳng định sự xuất hiện của các hạt vi nhựa chủ yếu đến từ hoạt động nhân sinh tại khu vực ven biển như nuôi trồng, khai thác thủy sản và rác thải sinh hoạt [6]. Kết quả của nghiên cứu này phù hợp với ghi nhận [1][2][3][4][5][6] của một số công bố đã thực hiện trước đây, nhưng khác biệt về tiêu chí phân loại là dựa vào nguồn gốc sản phẩm nhựa. Sự xuất hiện của các sản phẩm liên quan tới cả 6 nhóm nhựa cho thấy những xu hướng sử dụng đa dạng các sản phẩm nhựa cũng như những bất cập liên quan đến việc thu gom, xử lý rác thải nhựa nói riêng và rác thải sinh hoạt nói chung. ...
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This study is carried out for the purpose of collection, classification and assessment plastic waste component by household product origin. Survey results from 9/2020 to 01/2021 along the two banks of Nhue river, from Chem drain to Noi bridge showed that there is a clear difference between areas, the plastic waste appears depending on living habits, population characteristics and frequency/quantity of plastic products used by households. Six types of plastic PP, PET, HDPS, LDPE, PS-E, PVC appeared in 10 sampling areas with different quantities, weights and absent of the products derived from PS. The PET plastic group appeared with the highest number of 327 pieces with the weight of 1678.73 g and the lowest number was HDPE plastic with 44 pieces, but the lowest weight was recorded in the PP plastic group with 726.08 g. Size classification indicated that the number and weight of plastic pieces in different sizes are not proportional to each other. The weight of plastic pieces with size of 20-50 cm accounts for the majority of all the sampling areas, KV01 has the largest value accounting for 73.95% and the lowest is KV04 with 16.76%. The size of plastic pieces 0-<5 cm appears with a relatively low rate ranging from 0.01 to 6.35%, KV09 does not appear plastic pieces with this size. The remaining sizes including: 5-<10; 10-<15; 15-<20; 20-<50 and 50-1000 cm appear with the lowest rate of 1.88% (KV01, size of 50-1000 cm) to the highest of 52.17% (KV08, size of 15-<20 cm). The study results also show that people's living habits and demand for plastic products have a great influence on the distribution of plastic waste along the two banks of the river. Therefore, the community counseling/media programs for raising awareness of the people about the harmful effects of plastics and related products from plastic need to supplement.
... Plastic pollution is one of the most serious and pressing environmental concerns, as plastic is an indispensable resource from which affordable and useful products are obtained to satisfy the needs of human society (Andrady and Neal, 2009). However, it is also an emblem of waste, Science of the Total Environment 856 (2023) 159163 pollution and ecotoxicity, being an artificial polymeric material derived from fossil fuels such as petroleum (a source that will run out) and not readily biodegradable (Amobonye et al., 2021;Thompson et al., 2009). ...
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The recent use of bioplastics in agriculture is considered an ecological choice, aimed at limiting the environmental impact of plastics, in line with the Sustainable Development Goals of the United Nations. However, the impact of bioplastic residues on the environment is unclear as knowledge is lacking. This is the first study investigating the effect of a starch-based bioplastic on the growth and biochemical parameters of basil. Bioplastic was experimentally prepared and added to the soil at 2.5 % (w/w), corresponding to twice the concentration of plastic mulch film residues currently found in cultivated soils, in view of the increasing agricultural use of bioplastics. Basil plants were grown without (controls) and with bioplastic addition for 35 days, under controlled experimental conditions. Compared to the control, plants exposed to bioplastic showed stunted growth (in terms of shoot fresh weight, height, and number of leaves). Significant reductions in the content of chlorophyll, protein, ascorbic acid, and glucose were also observed. Finally, the treatment caused oxidative stress, as evidenced by the increased content of malondialdehyde in the shoots. The addition of bioplastic increased the electrical conductivity and reduced the cation exchange capacity of the cultivation soil. These results suggest that bioplastic in soil may promote the onset of stressful conditions for plant growth in a similar manner to plastic. They will be complemented by further investigations to unravel the mechanisms underlying these responses, involving different doses and types of bioplastics and other crop species.
... Of the two other phthalate isomers, phthalate (ortho-benzenedicarboxylic acid) is used mainly to prepare esters of phthalic acid (PAEs) which are used as plasticizers in various plastics-based products such as polyvinyl chloride (PVC), polyvinyl acetate (PVA), and polyethylene (PE), to improve extensibility, elasticity, and workability of the polymers [3,4]. Terephthalate (para-benzenedicarboxylic acid) is a major component of polyethylene terephthalate plastics [5]. Phthalic acid esters (PAEs) are used in the polymer industry since the 1930s. ...
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Background Environmental contamination from synthetic plastics and their additives is a widespread problem. Phthalate esters are a class of refractory synthetic organic compounds which are widely used in plastics, coatings, and for several industrial applications such as packaging, pharmaceuticals, and/or paints. They are released into the environment during production, use and disposal, and some of them are potential mutagens and carcinogens. Isophthalate (1,3-benzenedicarboxylic acid) is a synthetic chemical that is globally produced at a million-ton scale for industrial applications and is considered a priority pollutant. Here we describe the biochemical characterization of an enzyme involved in anaerobic degradation of isophthalate by the syntrophically fermenting bacterium Syntrophorhabdus aromaticivorans strain UI that activate isophthalate to isophthalyl-CoA followed by its decarboxylation to benzoyl-CoA. Results Isophthalate:Coenzyme A ligase (IPCL, AMP-forming) that activates isophthalate to isophthalyl-CoA was heterologously expressed in E. coli (49.6 kDa) for biochemical characterization. IPCL is homologous to phenylacetate-CoA ligase that belongs to the family of ligases that form carbon-sulfur bonds. In the presence of coenzyme A, Mg²⁺ and ATP, IPCL converts isophthalate to isophthalyl-CoA, AMP and pyrophosphate (PPi). The enzyme was specifically induced after anaerobic growth of S. aromaticivorans in a medium containing isophthalate as the sole carbon source. Therefore, IPCL exhibited high substrate specificity and affinity towards isophthalate. Only substrates that are structurally related to isophthalate, such as glutarate and 3-hydroxybenzoate, could be partially converted to the respective coenzyme A esters. Notably, no activity could be measured with substrates such as phthalate, terephthalate and benzoate. Acetyl-CoA or succinyl-CoA did not serve as CoA donors. The enzyme has a theoretical pI of 6.8 and exhibited optimal activity between pH 7.0 to 7.5. The optimal temperature was between 25 °C and 37 °C. Denaturation temperature (Tm) of IPCL was found to be at about 63 °C. The apparent KM values for isophthalate, CoA, and ATP were 409 μM, 642 μM, and 3580 μM, respectively. Although S. aromaticivorans is a strictly anaerobic bacterium, the enzyme was found to be oxygen-insensitive and catalysed isophthalyl-CoA formation under both anoxic and oxic conditions. Conclusion We have successfully cloned the ipcl gene, expressed and characterized the corresponding IPCL enzyme, which plays a key role in isophthalate activation that initiates its activation and further degradation by S. aromaticivorans. Its biochemical characterization represents an important step in the elucidation of the complete degradation pathway of isophthalate.
... Fossil-based plastics are durable, lightweight, inexpensive, resistant to degradation, and possess thermal and electrical insulation properties [26]. Therefore, global plastic production has increased from 1.5 million tons in the 1950s to approximately 367 million tons in 2020 [27], and this trend is assumed to continue in the coming years. ...
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Mitochondria are highly dynamic cellular organelles that perform crucial functions such as respiration, energy production, metabolism, and cell fate decisions. Mitochondrial damage and dysfunction critically lead to the pathogenesis of various diseases including cancer, diabetes, and neurodegenerative and cardiovascular disorders. Mitochondrial damage in response to environmental contaminant exposure and its association with the pathogenesis of diseases has also been reported. Recently, persistent pollutants, such as micro- and nanoplastics, have become growing global environmental threats with potential health risks. In this review, we discuss the impact of micro- and nanoplastics on mitochondria and review current knowledge in this field.
... Microplastics (MP) with dimensions less than 5 mm, formed either by fragmentation of larger plastic pieces (Eerkes-Medrano et al., 2015) or intentionally produced by industry for a specific purpose (Carr et al., 2016), is a subject of increasing environmental concern. Currently, there are hundreds of different types of plastic (Andrady and Neal, 2009), with 90% of global production corresponding to polyethylene (PE), polypropylene, polystyrene, polyvinyl chloride and polyethylene terephthalate (Geyer et al., 2017). Of these, all have already been identified in the environment in MP size (Horton et al., 2017;Klein et al., 2015). ...
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Lack of microplastics (MP) toxicity studies involving environmentally relevant concentrations and exposure times is concerning. Here we analyzed the potential adverse effects of low density polyethylene (LDPE) MP at environmentally relevant concentration in sub-chronic exposure to two amphipods Gmelinoides fasciatus and Gammarus lacustris, species that naturally compete with each other for their habitats. 14-day exposure to 2 μg/L (8 particles/L corresponding to low exposure) and 2 mg/L (∼8400 particles/L, corresponding to high exposure) of 53–100 μm LDPE MP were used to assess ingestion and egestion of MP, evaluate its effects on amphipod mortality, swimming ability and oxidative stress level. Both amphipod species were effectively ingesting and egesting LDPE MP. On the average, 0.8 and 2.5 MP particles were identified in the intestines of each amphipod exposed to 2 μg/L and 2 mg/L LDPE MP, respectively. Therefore, intestinal MP after 14-day exposure did not fully reflect the differences in LDPE MP exposure concentrations. Increased mortality of both amphipods was observed at 2 mg/L LDPE MP and in case of G. lacustris also at 2 μg/L exposure. The effect of LDPE on swimming activity was observed only in case of G. fasciatus. Oxidative stress marker enzymes SOD, GPx and reduced glutathione GSH varied according to amphipod species and LDPE MP concentration. In general G. lacustris was more sensitive towards LDPE MP induced oxidative stress. Overall, the results suggested that in MP polluted environments, G. lacustris may lose its already naturally low competitiveness and become overcompeted by other more resistant species. The fact that in the sub-chronic foodborne exposure to environmentally relevant and higher LDPE MP concentrations all the observed toxicological endpoints were affected refers to the potential of MP to affect and disrupt aquatic communities in the longer perspective.
Chapter
Emerging environmental contaminants (EECs) possess low degradation potential and environmental persistency. Pharmaceuticals and personal care products, plasticizers, pesticides, flame retardants, disinfection by-products, hormones, artificial sweeteners, benzotriazoles, 1,4-dioxane, and algal toxins are common EECs that are disposed of into the environment having microbial and bacterial resistance, potentially become carcinogenic, mutagenic, neurotoxic, and can disrupt/affect the endocrine system and environment negatively. Exogenous substances that even in microgram can mimic, antagonize, or modify the levels of endogenous hormones by affecting their synthesis, metabolism, transport, or actions are called endocrine disruptors. Post uses, most of these chemicals are released in wastewater that in one way or the other reaches into the rivers and drinking water supplies. Surface and agricultural run-offs are important sources of its entry. Due to microbial degradation, photolysis, and hydrolysis, many of these contaminants can transform in the environment into various forms that can affect both the environment and humans. Drug-metabolizing enzymes (DMEs) have crucial role in the metabolism, elimination, and detoxification of xenobiotics and drugs introduced into the human body. The tissues and organs of our body are well armed with diverse and various DMEs including phase I, phase II metabolizing enzymes, and phase III transporters, which are present in abundance either at the basal unstimulated level and/or are inducible at elevated level after exposure to compounds/xenobiotics. DMEs are important in biotransformation of endogenous compounds to more easily excretable forms, and its reduced metabolizing capacity can lead to toxic effects. To know about EECs is the need of time to minimize future damage and to monitor each class of compounds in the environment that will help to improve legislation on this situation.
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Plastics are versatile and pervasive materials, useful in countless applications and industries. Nevertheless, their high disposal and environmental stability are raising concerns and microplastics are now considered emerging food contaminants by moving all the way up the food chain. High level of uncertainty remains regarding the risks derived from human dietary exposure to microplastics. The aims of the study were to assess the occurrence of microplastics in salt for human consumption found on the Lebanese market, to estimate the Lebanese dietary exposure to microplastics from salt intake, and to suggest techniques that would ensure reduction of these microparticles in this commodity. All salt brands (n = 16) for human consumption present on the Lebanese market were collected and analyzed on two separate dates (n = 27), between September 2019 and December 2020. The presence of different types of microplastics was determined using the Fourier-Transform Infrared (FTIR) technique. Results showed that 81.3% of the assessed brands (n = 16) and 55.6% of the total samples (n = 27) were contaminated with microplastics. Moreover, all (100%) samples and replicates were contaminated with either microplastics or other foreign matter. The packed and coarse sea salt were more likely to be contaminated than those sold in bulk or the fine salt. The types of microplastics identified included polypropylene, thermoplastic elastomers, polyester and polyethylene. Plasticized rubber, benzyl butyl phthalate and other plasticizers were also detected by the FTIR in addition to hair, ant, human skin among others. It is estimated that each Lebanese adult would be exposed to 2372 microplastic particles. Year⁻¹ through salt intake. While the environmental impact of microplastics has received much attention, it is yet early to draw conclusions on the effect of long-term human exposure to dietary microplastics as more research and risk assessment are required. There is however, a pressing need to adopt novel techniques during salt production to minimize human exposure to these emerging contaminants.
Chapter
Microplastics are miniature plastic fragments that originate as a result of the advancement of commercial products as well as the breakdown of bigger plastics. Microplastics have been identified as a serious global environmental issue due to its poor waste management. This review covers the impact of microplastics on the soil ecosystem, their transit behaviour, and their impact on numerous organisms. The impact of microplastics on soil animals and plants, is influenced by the size, shape, and concentration of microplastics in the soil. Microplastic has been found in a variety of soil types, including agricultural, industrial, and coastal soils. Plastic particles in soil have increased, posing a major threat to soil ecosystem functioning, including the soil microbial population, nitrogen cycle, and higher organisms. The current review highlights and assimilates the findings of other scientists so that it can serve as a resource for readers and scientists dealing with microplastics, including toxicity, risk assessment in the environment, and microplastic treatment options.
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Plastics have transformed everyday life; usage is increasing and annual production is likely to exceed 300 million tonnes by 2010. In this concluding paper to the Theme Issue on Plastics, the Environment and Human Health, we synthesize current understanding of the benefits and concerns surrounding the use of plastics and look to future priorities, challenges and opportunities. It is evident that plastics bring many societal benefits and offer future technological and medical advances. However, concerns about usage and disposal are diverse and include accumulation of waste in landfills and in natural habitats, physical problems for wildlife resulting from ingestion or entanglement in plastic, the leaching of chemicals from plastic products and the potential for plastics to transfer chemicals to wildlife and humans. However, perhaps the most important overriding concern, which is implicit throughout this volume, is that our current usage is not sustainable. Around 4 per cent of world oil production is used as a feedstock to make plastics and a similar amount is used as energy in the process. Yet over a third of current production is used to make items of packaging, which are then rapidly discarded. Given our declining reserves of fossil fuels, and finite capacity for disposal of waste to landfill, this linear use of hydrocarbons, via packaging and other short-lived applications of plastic, is simply not sustainable. There are solutions, including material reduction, design for end-of-life recyclability, increased recycling capacity, development of bio-based feedstocks, strategies to reduce littering, the application of green chemistry life-cycle analyses and revised risk assessment approaches. Such measures will be most effective through the combined actions of the public, industry, scientists and policymakers. There is some urgency, as the quantity of plastics produced in the first 10 years of the current century is likely to approach the quantity produced in the entire century that preceded.
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Plastics are inexpensive, lightweight and durable materials, which can readily be moulded into a variety of products that find use in a wide range of applications. As a consequence, the production of plastics has increased markedly over the last 60 years. However, current levels of their usage and disposal generate several environmental problems. Around 4 per cent of world oil and gas production, a non-renewable resource, is used as feedstock for plastics and a further 3–4% is expended to provide energy for their manufacture. A major portion of plastic produced each year is used to make disposable items of packaging or other short-lived products that are discarded within a year of manufacture. These two observations alone indicate that our current use of plastics is not sustainable. In addition, because of the durability of the polymers involved, substantial quantities of discarded end-of-life plastics are accumulating as debris in landfills and in natural habitats worldwide. Recycling is one of the most important actions currently available to reduce these impacts and represents one of the most dynamic areas in the plastics industry today. Recycling provides opportunities to reduce oil usage, carbon dioxide emissions and the quantities of waste requiring disposal. Here, we briefly set recycling into context against other waste-reduction strategies, namely reduction in material use through downgauging or product reuse, the use of alternative biodegradable materials and energy recovery as fuel. While plastics have been recycled since the 1970s, the quantities that are recycled vary geographically, according to plastic type and application. Recycling of packaging materials has seen rapid expansion over the last decades in a number of countries. Advances in technologies and systems for the collection, sorting and reprocessing of recyclable plastics are creating new opportunities for recycling, and with the combined actions of the public, industry and governments it may be possible to divert the majority of plastic waste from landfills to recycling over the next decades.
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In the last decades, the availability of sophisticated analytical chemistry techniques has facilitated measuring trace levels of multiple environmental chemicals in human biological matrices (i.e. biomonitoring) with a high degree of accuracy and precision. As biomonitoring data have become readily available, interest in their interpretation has increased. We present an overview on the use of biomonitoring in exposure and risk assessment using phthalates and bisphenol A as examples of chemicals used in the manufacture of plastic goods. We present and review the most relevant research on biomarkers of exposure for phthalates and bisphenol A, including novel and most comprehensive biomonitoring data from Germany and the United States. We discuss several factors relevant for interpreting and understanding biomonitoring data, including selection of both biomarkers of exposure and human matrices, and toxicokinetic information.
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The chief characteristic that determines the quantity of energy recoverable from the combustion of mixed waste paper (MWP) is the thermal energy of the material as measured by a bomb calorimeter. Mixed waste paper can be divided into 11 groups, according to the qualities of the paper, such as newspaper, boxboard, white office paper, coloured office paper, envelopes, treated paper (NCR), beverage and milk boxes, glossy paper, kraft, cardboard, and tissue. Individual thermal energies per weight of these groups (components of mixed waste paper) and mixed waste paper itself are determined separately and ranges established for their thermal energies. Using individual thermal energies of mixed waste paper components, the thermal energy of a typical sample of mixed waste paper is estimated. Based on this work it is concluded that it is possible to estimate the quantity of energy recoverable from a known amount and composition of mixed waste paper by separating the sample into its components and using the weight fraction and individual thermal energies of each component.
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The chief characteristic that determines the quantity of energy recoverable from the combustion of mixed waste paper (MWP) is the thermal energy of the material as measured by a bomb calorimeter. Mixed waste paper can be divided into 11 groups, according to the qualities of the paper, such as newspaper, boxboard, white office paper, coloured office paper, envelopes, treated paper (NCR), beverage and milk boxes, glossy paper, kraft, cardboard, and tissue. Individual thermal energies per weight of these groups (components of mixed waste paper) and mixed waste paper itself are determined separately and ranges established for their thermal energies. Using individual thermal energies of mixed waste paper components, the thermal energy of a typical sample of mixed waste paper is estimated. Based on this work it is concluded that it is possible to estimate the quantity of energy recoverable from a known amount and composition of mixed waste paper by separating the sample into its components and using the weight fraction and individual thermal energies of each component.
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Forecasting material flows is essential for sound policy making on issues relating to waste management. This paper presents the results of the plastics materials flow analysis (MFA) for India. In the recent past, India has witnessed a substantial growth in the consumption of plastics and an increased production of plastic waste. Polyolefins account for the major share of 60% in the total plastics consumption in India. Packaging is the major plastics consuming sector, with 42% of the total consumption, followed by consumer products and the construction industry. The relationship observed between plastic consumption and the gross domestic product for several countries was used to estimate future plastics consumption (master curve). Elasticities of the individual material growth with respect to GDP were established for the past and for the next three decades estimated for India thereby assuming a development comparable with that of Western Europe. On this basis, the total plastics consumption is projected to grow by a factor of 6 between 2000 and 2030. The consumption of various end products is combined with their corresponding lifetimes to calculate the total waste quantities. The weighted average lifetime of plastics products was calculated as 8 years. Forty-seven percent of the total plastics waste generated is currently recycled in India; this is much higher than the share of recycling in most of the other countries. The recycling sector alone employs as many people as the plastics processing sector, which employs about eight times more people than the plastics manufacturing sector. Due to the increasing share of long-life products in the economy, and consequently in the volume of waste generated, the share of recycling will decrease to 35% over the next three decades. The total waste available for disposal (excluding recycling) will increase at least 10-fold up to the year 2030 from its current level of 1.3 million tonnes.
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Components used in plastics, such as phthalates, bisphenol A (BPA), polybrominated diphenyl ethers (PBDE) and tetrabromobisphenol A (TBBPA), are detected in humans. In addition to their utility in plastics, an inadvertent characteristic of these chemicals is the ability to alter the endocrine system. Phthalates function as anti-androgens while the main action attributed to BPA is oestrogen-like activity. PBDE and TBBPA have been shown to disrupt thyroid hormone homeostasis while PBDEs also exhibit anti-androgen action. Experimental investigations in animals indicate a wide variety of effects associated with exposure to these compounds, causing concern regarding potential risk to human health. For example, the spectrum of effects following perinatal exposure of male rats to phthalates has remarkable similarities to the testicular dysgenesis syndrome in humans. Concentrations of BPA in the foetal mouse within the range of unconjugated BPA levels observed in human foetal blood have produced effects in animal experiments. Finally, thyroid hormones are essential for normal neurological development and reproductive function. Human body burdens of these chemicals are detected with high prevalence, and concentrations in young children, a group particularly sensitive to exogenous insults, are typically higher, indicating the need to decrease exposure to these compounds.