No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Toxicity of Heavy Metals on Embryogenesis and Larvae of the Marine Sedentary Polychaete Hydroides elegans
Abstract
The toxicity of heavy metals to marine invertebrates has been widely investigated; however, the effects on marine sedentary polychaetes have largely been ignored. The toxicity of copper, aluminium, lead, nickel, and zinc on fertilization, embryogenesis, and larvae of Hydroides elegans was examined in laboratory acute-toxicity tests. Exposure to metal during fertilization or early developmental stages leads to fertilization block and arrested development, which resulted in morphologic abnormalities in embryo and larvae. Fertilization rate showed a drastic decrease at the highest metal concentration tested. Embryos of H. elegans showed a differential response to metals, and the responses were stage-specific. The different morphologic effects of heavy metals reflect differentiation of the early embryonic cells. For individual metals, the toxicity ranking for 24-hour trochophore larvae was Cu > Al > Pb > Ni > Zn, with EC(50) values of 0.122, 0.210, 0.231, 0.316, and 0.391 mg l(-1), respectively. Rate of larval development and embryogenesis were the most sensitive end points, although the latter is more advisable for routine assessment of seawater quality because of its greater simplicity. In addition to bivalves and sea urchins, polychaete embryos can provide biologic criteria for seawater quality taking into account the sensitivity of a polychaete and contributing to the detection of harmful chemicals with no marked effect on the species currently in use in seawater quality bioassays.
... The tube-building serpulid polychaete H. elegans (Haswell), which is widespread in tropical and subtropical coastal waters, reproduces all year long (Gopalakrishnan et al., 2007. Because it accumulates in shallow water, this species is easy to collect. ...
... Because it accumulates in shallow water, this species is easy to collect. Previous research have shown that gametes from H. elegans could be utilised for toxicity investigations because they are easy to keep in the lab and can be easily induced to spawn (Xie et al., 2005;Gopalakrishnan et al., 2007Gopalakrishnan et al., , 2008Thilagam et al., 2008). ...
... Gametes of H. elegans were prepared from the modified procedure adopted from Gopalakrishnan et al. (2007). Briefly a ripe H. elegans with a 5 cm tube length was preferred for conducting the test. ...
... Hydroides elegans, a sedentary polychaete prevalent in temperate regions, produces viable gametes throughout the year [10]. A previous study employing H. elegans embryos and larvae demonstrated that heavy metal exposure and effluents caused fertilization obstruction and developmental arrest [11,12]. Although several studies on H. elegans species are available, less attention has been paid to the use of H. elegans gametes (eggs and sperm) in evaluating the effects of pollutants in seawater. ...
... Polychaetae worms were acclimatized to laboratory conditions for a week; during acclimatization, the seawater was changed daily. Dissolved oxygen (7 ± 2 mg/L), salinity (34 ± 1 ppt), temperature (28 ± 1 • C), and pH (8.1 ± 0.1) were maintained in the glass aquarium, and the light was provided in a light-dark cycle of about 14:10 h [11]. ...
... Three data points for each sampling station were combined to give the average and standard deviation (SD) of nine samples (3 triplicate × 3 repetitions), which were then statistically analyzed. Though blastula stage was reached within 2 h in the reference water, the experiment was terminated after 3 h, or when most of the embryos reached the blastula stage, by adding 10% neutral buffered formalin prepared in seawater, and the success rate of the respective embryonic stage was confirmed by counting the first 100 embryos encountered and grading them as developed or undeveloped [10,11]. Photomicrographs were taken using a Pentax K1000 (Tokyo, Japan) camera mounted to a Weswox microscope. ...
To investigate the impact of environmental contaminants on the early life stages of the marine polychaetae Hydroides elegans, a toxicity test was designed. In our previous study, we reported gametes and embryos of H. elegans were sensitive to heavy metal pollution and effluents. In continuation of this, we used H. elegans gametes to assess the water quality of samples taken along the southeast coast of India. The samples were collected from five different locations of the Chennai coast (Muttu Kadu, Neelangarai, Marina, Royapuram, and Ennore), and two different bioassay toxicity tests were performed. Sperm and eggs were pre-exposed to water samples taken from different locations to assess the water quality. Water samples collected from Ennore station and the Royapuram fish landing center were found to be more polluted than those collected from other locations. Sperm were shown to be more sensitive than eggs. The different morphological effects produced by water samples reflected the defects in the early differentiation of embryonic cells. Since fertilization can be inhibited in the presence of any xenobiotic, both fertilization and early development could be used as a biological indicator for a rapid bioassay to monitor marine pollution. The percentage of successful fertilization and early development was comparatively higher at the reference site (Neelangarai) and in the seawater samples collected from Marina. The physicochemical characteristics of the seawater from these sampling stations corroborated the findings of this investigation. Our results showed that H. elegans gametes were highly sensitive to any contaminant present in the seawater, and confirmed previous findings that this polychaetae can be routinely used as a test organism for ecotoxicological bioassays in tropical and subtropical regions.
... Lithium at 2-3 % of ∼3900 mg/L (approximately 78-117 mg/L of Li) showed visible morphological malformations. Other studies already highlighted the capacity of various metals to induce malformations and development inhibition in polychaetes (Gopalakrishnan et al., 2008(Gopalakrishnan et al., , 2007. Cooper (0.5 mg/L), aluminium and lead (1 mg/L), as well as nickel and zinc (5 mg/L) caused abnormalities in embryos of polychaete Hydroides elegans (Gopalakrishnan et al., 2007). ...
... Other studies already highlighted the capacity of various metals to induce malformations and development inhibition in polychaetes (Gopalakrishnan et al., 2008(Gopalakrishnan et al., , 2007. Cooper (0.5 mg/L), aluminium and lead (1 mg/L), as well as nickel and zinc (5 mg/L) caused abnormalities in embryos of polychaete Hydroides elegans (Gopalakrishnan et al., 2007). ...
The Lithium industry has been expanding worldwide over the last decades and projections expect an increasing demand for its production in the next years. It has been identified as an emerging pollutant and it occurs widely in aquatic environments, raising concern about its effects on ecosystems. Besides the increasing research on this topic, there is still limited understanding and discussion on the marine and coastal implications of Li occurrence. The present review aims to fill these knowledge gaps by analysing the literature concerning Li occurrence and its effects on marine and coastal ecosystems, including transition areas. Since 1960, the number of publications has increased, especially over the last decade, and available information has reported Li in water and sediments of these areas, while few studies investigated Li in tissues of biota. Among all the studied ecosystems, Chile reported one of the highest Li concentrations. Regarding the adverse effects of Li in aquatic organisms, Bacillariophyceae, Scyphozoa, Bivalvia, Gastropoda, Cephalopoda, Polychaeta, Malacostraca, Echinoidea and Actinopteri were the studied taxonomic classes, and development inhibition, malformations, cellular and metabolic alterations, and behaviour changes were some of the observed impacts. This review might be particularly important in the mitigation of Li pollution and in the implementation of new directives and thresholds, as it highlights the impacts of Li and the urgent need to address new solutions and alternatives, meeting the Agenda 2030 for sustainable development.
... (zOTU15) demonstrated the opposite pattern, being very abundant in the port samples, while almost no present at the aquaculture site. Considering that the port and aquaculture sites in Northern Adriatic are in close geographical proximity (i.e., Port of Pula and Lim Bay; approximately 30 km), local environmental conditions, such as high pollution at the port and more food resources at the aquaculture site among others, were the most likely factors causing these community patterns (Gopalakrishnan et al., 2007(Gopalakrishnan et al., , 2008Fuentes et al., 2010;Purcell, 2012;Dobaradaran et al., 2018;Ezgeta-Balić et al., 2020;unpublished data). We acknowledge that the changes in ecosystems and communities due to human impact would be better assessed if our study would include sites unaffected by anthropogenic activitiespristine sites. ...
... Therefore, the unpolluted environment in Lim Bay was favorable for the proliferations of some species, while heavily polluted area of the shipping port supported other ones. For example, H. elegans has been reported to be highly sensitive to heavy metals, which can lead to a drastic decrease in its fertilization rate (Gopalakrishnan et al., 2007(Gopalakrishnan et al., , 2008Dean, 2008). As port areas are considered to suffer greatly from heavy metal pollution released from ships' hulls and inner surfaces of ballast tanks (Dobaradaran et al., 2018;unpublished data), it was not a surprise that H. elegans was abundant in the aquaculture site during its spawning season, but undetected in the nearby port. ...
Coastal ecosystems globally are exposed to the most pervasive anthropogenic activities, caused by a suite of human infrastructure and enterprises such as shipping ports, aquaculture facilities, fishing, and tourism. These anthropogenic activities may lead to changes in ecosystem biodiversity, followed by loss of ecosystem functioning and services. Shipping industry and aquaculture have also been recognized as the main vectors for introduction of marine nonindigenous species (NIS) worldwide. In this study, we used DNA metabarcoding-based methods to investigate plankton biodiversity under varying anthropogenic pressures (shipping and bivalve aquaculture) along the eastern Adriatic coast (the northernmost part of the Mediterranean Sea). Our comparative assessment revealed similar community structures among investigated coastal locations (Northern, Central and Southern Adriatic). When the whole plankton communities were considered, they did not differ significantly between port and aquaculture sites. However, the proportion of the unique zOTUs in the port samples was remarkably higher than that in aquaculture sites (40.5% vs 8.2%), indicating that port areas may receive higher abundance and species richness of NIS than aquaculture sites. Further important difference between the two types of anthropogenically impacted habitats was a high abundance of three notorious invaders – M. leidyi, M. gigas, and H. elegans in late summer at the aquaculture site in Northern Adriatic. Therefore, the plankton community of the area is under pressure not only from aquaculture activities, but also establishment of NIS. Port areas are probably under greater introduction pressure from NIS, but aquaculture sites may experience greater community changes due to their establishment.
... A study done by Naddy et al. in 2007 established that an ambient silver concentration of 35 g/L had an 80% mortality rate for the cladoceran species Ceriodaphnia dubia, an aquatic invertebrate [8]. While it was not specifically looking at silver, an experiment by Gopalakrishnan et al. (2007) examining toxicity of heavy metals on the marine polychaete Hydroides elegans found that heavy metal exposure leads to fertilization block and arrested development [17]. Another study, by Ward et al. in 2006, investigated the chronic toxicity of silver to the sea urchin Arbacia punctulata and looked at effects on fertilization, embryonic viability and adult survival [7]. ...
... A study done by Naddy et al. in 2007 established that an ambient silver concentration of 35 g/L had an 80% mortality rate for the cladoceran species Ceriodaphnia dubia, an aquatic invertebrate [8]. While it was not specifically looking at silver, an experiment by Gopalakrishnan et al. (2007) examining toxicity of heavy metals on the marine polychaete Hydroides elegans found that heavy metal exposure leads to fertilization block and arrested development [17]. Another study, by Ward et al. in 2006, investigated the chronic toxicity of silver to the sea urchin Arbacia punctulata and looked at effects on fertilization, embryonic viability and adult survival [7]. ...
Considered one of the most toxic heavy metals, interest in silver (both ionic and bound forms) has increased over the past few years due to the production of consumer goods containing Ag⁺-releasing nanoparticles. Investigation into acceptable environmental limits has generated a substantial amount of evidence that even at very low concentrations, silver exposure is detrimental to organism health. This study employed the echinoderm fertilization assay to evaluate acute silver toxicity to a marine invertebrate, Echinarachnius parma. Gametes were procured from E. parma and fertilization success under control conditions was compared to that at varying treatment concentrations of silver nitrate. Exposure to silver nitrate significantly decreased percent fertilization in all treatment concentrations. Remarkably, at concentrations as low as 10⁻⁹ M AgNO₃ percent fertilization decreased by 20-30% compared to the control. The results of this study are consistent with the existing literature, adding to the expanding collection of data that emphasizes the need for more stringent environmental silver regulation criteria in order to ensure the protection of aquatic ecosystems.
... Developing bioassays to assess the effects of environmental conditions on organisms is a focus of many scientific disciplines including aquaculture (Kime et al., 2001), ecotoxicology (Macken et al., 2008) and climate change research (Falkenberg et al., 2013;Gazeau et al., 2010). For organisms that release gametes freely into the water column e so-called "broadcast spawning organisms" e the sensitivity and ecological relevance of reproductive endpoints to modified environmental conditions is especially relevant, and has led to their widespread use in bioassays (Lewis and Watson, 2012;Nipper et al., 1993;Watanabe et al., 2007). ...
... For organisms that release gametes freely into the water column e so-called "broadcast spawning organisms" e the sensitivity and ecological relevance of reproductive endpoints to modified environmental conditions is especially relevant, and has led to their widespread use in bioassays (Lewis and Watson, 2012;Nipper et al., 1993;Watanabe et al., 2007). Many bioassays exploit reproductive endpoints such as fertilisation, which requires the collection of both male and female gametes from the species of interest, as well as successfully fertilising those gametes in vitro (Caldwell et al., 2011;Gopalakrishnan et al., 2007;Ross and Bidwell, 2001). These requirements can be difficult to meet as viable eggs may be hard to collect and fertilisation usually requires the careful application of species-specific protocols (Strathmann, 1987), which may not exist for many species of interest (Fabbrocini et al., 2010). ...
... Metal ions showed similar toxicity between each others (EC50 values 0.28 mg/L and 0.096 mg/L for Cd 2 þ and Cu 2 þ , respectively); in particular copper showed EC 50 values slightly lower than cadmium at all salinities, differently on what observed in Gopalakrishnan et al. (2007Gopalakrishnan et al. ( , 2008 on H. elegans, where cadmium exhibited EC 50 values about 10-fold lower than copper. It could be hypothesized that increased amounts of metals inhibit natural cell functions exerting in toxicity through displacement of other metals at binding sites (George, 1990). ...
... Gopalakrishnan et al. (2008). e Gopalakrishnan et al. (2007). f Bellas et al. (2005). ...
Ficopomatus enigmaticus is an ubiquitous fouling reef-forming species, easy to sample and recognize, diecious with gamete spawning along different seasons in different salinity conditions. Due to its characteristics it could become a good candidate for the monitoring of both marine and brackish waters. The suitability of F. enigmaticus as a promising model organism in ecotoxicological bioassays was evaluated by a sperm toxicity and a larval development assay. The fertilization rate in different salinity conditions (range 5-35‰) was first assessed in order to detect the salinity threshold within which profitably perform the assays. Afterward copper (Cu(2+)), cadmium (Cd(2+)), sodium dodecyl sulfate (SDS) and 4-n-nonylphenol (NP) were used as reference toxicants in exposure experiments with spermatozoids (sperm toxicity assay) and zygotes (larval development assay). A dose-response effect was obtained for all tested toxicants along all salinity conditions except for 5‰ salinity condition where a too low (<30%) fertilization rate was observed. NP showed the highest degree of toxicity both in sperm toxicity and larval development assay. In some cases the results, expressed as EC50 values at 35‰ salinity condition, were similar to those observed in the literature for marine organisms such as the sea urchin (Paracentrotus lividus) and the marine serpulid Hydroides elegans, while the exposure of F. enigmaticus spermatozoids' to Cd(2+) and NP resulted in toxicity effects several orders of magnitude higher than observed in P. lividus. Spermatozoids resulted to be slightly more sensitive then zygotes to all different toxicants.
... Various metrics for embryo toxicity in aquatic species have been defined, such as developmental changes and delays, failure to develop, and other changes in physiological function after exposure to toxicants. For example, embryo development has been used as an indicator for studying toxicity of endocrine disruptors in copepods (Forget-Leray et al. 2005), heavy metals in polychaetes (Gopalakrishnan et al. 2007), mysids (Lussier et al. 1985) and echinoids (Warnau et al. 1996), and nanoparticles in Danio rerio (Cheng et al. 2007) and Pimephales promelas (Laban et al. 2010). Several embryo development endpoints have been used for Daphnia magna, including arrested embryo development and deformities (Abe et al. 2000(Abe et al. , 2001 release of both embryonic membranes, and the formation of the caudal spine (Sobral et al. 2001). ...
... Embryo toxicity assays within the field of environmental toxicology have been a growing area of interest. Heavy metals (Gopalakrishnan et al. 2007;Khangarot and Das 2009;Lussier et al. 1985;Warnau et al. 1996), endocrine disruptors (Forget-Leray et al. 2005;Gray et al. 1999;Mu and LeBlanc 2002b), disinfectants (Ton et al. 2012), and nanomaterials (Cheng et al. 2007;Wiench et al. 2009) have all been found to inhibit or alter embryonic development in a variety of organisms. Proteome and transcriptome assessments offer improved sensitivity (Mu and LeBlanc 2002a;Soetaert et al. 2006Soetaert et al. , 2007, but are invasive and require the destruction of small organisms such as D. magna embryos. ...
Embryos, unlike adults, are typically sessile, which allows for an increase in the available metrics that can be used to assess chemical toxicity. We investigate Daphnia magna development rate and oxygen consumption as toxicity metrics and compare them to arrested embryo development using four different techniques with potassium cyanide (KCN) as a common toxicant. The EC50 (95 % CI) for arrested development was 2,535 (1,747-3,677) μg/L KCN. Using pixel intensity changes, recorded with difference imaging, we semi-quantitatively assessed a decrease in development rate at 200 μg/L KCN, threefold lower than the arrested development lowest observed effect concentration (LOEC). Respirometry and self-referencing (SR) microsensors were two unique techniques used to assess oxygen consumption. Using respirometry, an increase in oxygen consumption was found in the 5 μg/L KCN treatment and a decrease for 148 μg/L, but no change was found for the 78 μg/L KCN treatment. Whereas, with SR microsensors, we were able to detect significant changes in oxygen consumption for all three treatments: 5, 78, and 148 μg/L KCN. While SR offered the highest sensitivity, the respirometry platform developed for this study was much easier to use to measure the same endpoint. Oxygen consumption may be subject to change during the development process, meaning consumption assessment techniques may only be useful only for short-term experiments. Development rate was a more sensitive endpoint though was only reliable four of the six embryonic developmental stages examined. Despite being the least sensitive endpoint, arrested embryo development was the only technique capable of assessing the embryos throughout all developmental stages. In conclusion, each metric has advantages and limitations, but because all are non-invasive, it is possible to use any combination of the three.
... 2004). As there were no limits set for zinc, we referred to the concentrations used by Gopalakrishnan et al. (2007) on polychaetes. The results are reported as mean ± SE. ...
... Although this is an essential metal, it appears to be more toxic than the other metals, as it affected all the parameters tested. This is in agreement with the finding by Gopalakrishnan et al. (2007) of a zinc-induced developmental arrest and embryo abnormality in the polychaete Hydroides elegans. The reversible effect of zinc and mercury indicates that this transient toxicity does not affect fertilization, but it does give rise to a long-term negative effect on hatching rate and larval morphology. ...
Environmental pollution due to anthropogenic activities may exert an adverse
impact on the reproductive mechanisms of animals. In particular, environmen-
tal chemicals introduced into seawater are able to disrupt the normal develop-
ment and function of the reproductive system of marine animals. In this study,
we have used the whole-cell voltage clamp technique to examine the effects of
four metals – lead, cadmium, mercury, and zinc – on reproductive mechanisms
of the marine invertebrate Ciona intestinalis (ascidians). In particular, we mea-
sured the effect of metals on plasma membrane electrical properties, the
steady-state conductance, the fertilization current in the mature oocyte, and
larval development. Results show that oocyte voltage-gated sodium currents are
significantly reduced by all four metals, steady-state conductance is affected
only by zinc, and post-fertilization contraction is inhibited only by lead. The
fertilization current is suppressed in the presence of zinc and mercury. Embryo
development up to larval stage is inhibited by zinc and mercury exposure with
a reversible effect; however, a long-term effect on larval morphology was
observed. After exposure to cadmium, fertilization occurs but gives rise to
abnormal larval development. These findings highlight the point that exposure
to metals represents a significant risk factor for the physiology of reproduction
of marine species and suggest a possible role of the C. intestinalis as a bioindi-
cator for marine pollution monitoring.
... All have been shown to have significant impacts on a variety of life stages in polychaetes, but the sensitivity of stages and species can differ markedly (e.g. Conner, 1972;Eisler and Hennekey, 1977;Oshida et al., 1981;Reish and Gerlinger, 1984;Mauri et al., 2003;Mendez and Green-Ruiz, 2006;Gopalakrishnan et al., 2007). It is, therefore, important to assess the relative toxicities of a variety of metals on one species and one life-stage. ...
... However, our study suggests that N. virens are more sensitive to copper than other species. Gopalakrishnan et al. (2007) calculated a 24 h LC 50 for Hydroides elegans of 122 µg l !1 for incubation from fertilization to trochophore and a 96 h LC 50 of 180 µg l !1 was calculated for Capitella capitata larvae (Reish et al., 1976). Our results confirm that copper is the most toxic to nectochaete larvae of the five metals tested, but to fully assess the effects all key developmental stages must be tested as responses to toxicants can be stage specific (Kobayashi, 1980). ...
Nectochaete larvae of the ecologically and economically important ragworm, Nereis virens, were exposed to cadmium, chromium, copper, lead and zinc dissolved in seawater to nominal concentrations ranging from 0 to 5000 μg l. Copper was the most toxic (mean LC50 of 76.5 μg l ± 95% CI 73.8–79.2 after 96 h exposure) and so was used for subsequent experiments. Exposure of gametes to greater than 500 μg l copper for 2 or 4 h at 10°C prior to fertilization, or a 10 min exposure during fertilization, significantly reduced embryo developmental success. The effect of copper on larval settlement was also assessed using sediment spiked to a range of concentrations (0, 50, 250, 500, 1000 mg kg!1 dry weight). Significantly fewer larvae were found in sediment of $250 mg kg!1 in comparison to the control or the 50 mg kg!1 treatment. Assessment of living larvae also confirmed a significant reduction in settlement, but in all treatments compared to the control, although the number of dead larvae also increased as the concentrations increased. These effects may have important implications for reproductive success and recruitment of N. virens to polluted sediments.
... The period for subsequent larval development is also short (4-5 days) under optimal conditions (Qiu and Qian 1997). Many studies, therefore, use H. elegans as a test organism in ecotoxicity bioassays to evaluate the impact of heavy metals on the marine environment (Xie et al. 2005;Qiu et al. 2005Qiu et al. , 2007Gopalakrishnan et al. 2007Gopalakrishnan et al. , 2008. The effect of Cu on H. elegans has been investigated and results show that embryogenesis, larval development, and larvae are highly sensitive to Cu stress (Xie et al. 2005;Gopalakrishnan et al. 2007). ...
... Many studies, therefore, use H. elegans as a test organism in ecotoxicity bioassays to evaluate the impact of heavy metals on the marine environment (Xie et al. 2005;Qiu et al. 2005Qiu et al. , 2007Gopalakrishnan et al. 2007Gopalakrishnan et al. , 2008. The effect of Cu on H. elegans has been investigated and results show that embryogenesis, larval development, and larvae are highly sensitive to Cu stress (Xie et al. 2005;Gopalakrishnan et al. 2007). By culturing newly-developed trochophores to juveniles under Cu stress, Xie et al. (2005) also found that Cu inhibits larval settlement in H. elegans. ...
Copper (Cu) contamination is a potential threat to the marine environment due to the use of Cu-based antifouling paints. Cu stress on larval settlement of the polychaete Hydroides elegans was investigated, and this was linked to Cu stress on biofilms and on the biofilm development process. The inductiveness of young biofilms was more easily altered by Cu stress than that of old biofilms, indicating the relative vulnerability of young biofilms. This might result from changes in bacterial survival, the bacterial community composition and the chemical profiles of young biofilms. Cu also affected biofilm development and the chemical high performance liquid chromatograph fingerprint profile. The results indicate that Cu affected larval settlement mainly through its effect on the process of biofilm development in the marine environment, and the chemical profile was crucial to biofilm inductiveness. It is strongly recommended that the effects of environmentally toxic substances on biofilms are evaluated in ecotoxicity bioassays using larval settlement of invertebrates as the end point.
... Taxa in meroplankton are widely used as bioindicators (both as adults and larvae) of marine pollution and as ecotoxicological test species to evaluate the effects of various contaminants. Several studies have reported the impacts of pollutants e.g., heavy metals (Reish et al. 1974;Gopalakrishnan et al. 2007), PAHs mixtures (Chandler et al. 1997) and Benzo(a)pyrene (Jha et al. 1996) on polychaetes, concluding that exposure to contaminants, both at early lifeand adult-stages, has been linked to several disruptions in (larval) survival, developmental abnormalities, and instability (as pointed also by Lewis et al. 2008;García-Alonso et al. 2014). However, the mentioned studies focused on single-species experiments, using stock cultures, thus overlooking the resilience fostered by the broader marine communities that surround these species, particularly the pollutants biodegrading capacity of natural bacterioplankton (Genitsaris et al. 2023). ...
Exhaust Gas Cleaning Systems, i.e., “scrubbers”, have been installed on ships as an alternative to low sulfur maritime fuels. The effluent that open-loop systems discharge is a cocktail of low pH seawater with high concentrations of PAHs, metals and particles, and poses concern to the marine environment. Metazooplankton are the first metazoan responders to exogenic pressures, thus understanding their responses to scrubber effluents will provide insights of shipping impacts on higher trophic levels of marine ecosystems. In the present community ecotoxicology study, experimental jars were utilized to examine scrubber effluent effects on the small-size fraction of coastal metazooplankton populations (Thessaloniki Bay, Eastern Mediterranean Sea). Treatments were set up by applying two scenarios: (a) low scrubber effluent content (1% v/v; LS) and (b) high scrubber effluent content in seawater (10% v/v; HS) compared with seawater; Control (C). Overall, a non-significant change in copepod’s developmental stages (nauplii) was documented in LS treatments compared to controls (C: 1,179; LS: 988 ind per experimental jar), contrary to the significant effects detected in HS treatments (674 ind per experimental jar). The responses were species-specific, with Oithona responding positively and exhibiting positive growth rates across treatments (C: 0.3; LS: 0.2; HS: 0.2 d⁻¹). Community network analysis revealed greater connectivity of metazooplankton species and groups in the Control and LS treatments compared to HS. Overall, no adverse effects in the 1% scrubber effluent treatments were reported in the plankton copepods community in our community ecotoxicological experiment, complementing the respective results on natural bacterioplankton and phytoplankton communities.
... For example, the tube of Sabella spallanzanii is an important compartment in metal retention and suitable for evaluation of the pollution by traced elements [460], while Branchiomma bairdi and B. luctuosum, invasive sabellids in the Mediterranean, can accumulate high concentrations of arsenic (As), cadmium (Cd), chromium (Cr) and lead (Pb), considered to be priority toxic or ubiquitous persistent, bioaccumulative and toxic (PBT) substances under the EU Water Framework Directive [461]. Some studies have focused on the effects of heavy metals on larval development and metamorphosis using serpulid larvae (Hydroides elegans: [462,463]); Galeolaria caespitosa: [464]). ...
Sabellida Levinsen, 1883 is a large morphologically uniform group of sedentary annelids commonly known as fanworms. These annelids live in tubes made either of calcareous carbonate or mucus with agglutinated sediment. They share the presence of an anterior crown consisting of radioles and the division of the body into thorax and abdomen marked by a chaetal and fecal groove inversion. This study synthesises the current state of knowledge about the diversity of fanworms in the broad sense (morphological, ecological, species richness), the species occurrences in the different biogeographic regions, highlights latest surveys, provides guidelines for identification of members of each group, and describe novel methodologies for species delimitation. As some members of this group are well-known introduced pests, we address information about these species and their current invasive status. In addition, an overview of the current evolutionary hypothesis and history of the classification of members of Sabellida is presented. The main aim of this review is to highlight the knowledge gaps to stimulate research in those directions.
... The genus is one of the most ecologically and economically important groups of marine invertebrates (Lewis et al., 2006;Streftaris and Zenetos, 2006;Link et al., 2009) because it includes notorious biofoulers and bioinvaders that have been transported around the world on ship hulls, leading to high economic impact due to the costs associated with removal of the tubes from submerged structures (Hadfield, 1998). Their ecological importance has driven studies on taxonomy (e.g., Pillai, 1972;ten Hove, 2002, 2003;Sun et al., 2015), phylogeny (Sun et al., 2012, developmental, larval ecology and biofouling (e.g., Hadfield, 1998Hadfield, , 2011Qiu and Qian, 1998;Qian, 1999), ecotoxicology (e.g., Gopalakrishnan et al., 2007;Vijayaragavan and Vivek Raja, 2018), and climate change (e.g., Chan et al., 2012;Lane et al., 2013). Investigations of mitochondrial markers such as partial sequences of cytochrome c oxidase I (cox1) and cytochrome b (cob) genes have shown a significant variability of these sequences within Hydroides (Sun et al., 2012, indicating fast evolution of mitochondrial genes in this genus, yet our knowledge on the mitochondrial genomes of this group is very limited. ...
Mitochondrial genomes are frequently applied in phylogenetic and evolutionary studies across metazoans, yet they are still poorly represented in many groups of invertebrates, including annelids. Here, we report ten mitochondrial genomes from the annelid genus Hydroides (Serpulidae) and compare them with all available annelid mitogenomes. We detected all 13 protein coding genes in Hydroides spp., including the atp8 which was reported as a missing gene in the Christmas Tree worm Spirobranchus giganteus, another annelid of the family Serpulidae. All available mitochondrial genomes of Hydroides show a highly positive GC skew combined with a highly negative AT skew – a feature consistent with that found only in the mitogenome of S. giganteus. In addition, amino acid sequences of the 13 protein-coding genes showed a high genetic distance between the Hydroides clade and S. giganteus, suggesting a fast rate of mitochondrial sequence evolution in Serpulidae. The gene order of protein-coding genes within Hydroides exhibited extensive rearrangements at species level, and were different from the arrangement patterns of other annelids, including S. giganteus. Phylogenetic analyses based on protein-coding genes recovered Hydroides as a monophyletic group sister to Spirobranchus with a long branch, and sister to the fan worm Sabellidae. Yet the Serpulidae+Sabellidae clade was unexpectedly grouped with Sipuncula, suggesting that mitochondrial genomes alone are insufficient to resolve the phylogenetic position of Serpulidae within Annelida due to its high base substitution rates. Overall, our study revealed a high variability in the gene order arrangement of mitochondrial genomes within Serpulidae, provided evidence to question the conserved pattern of the mitochondrial gene order in Annelida and called for caution when applying mitochondrial genes to infer their phylogenetic relationships.
... For instance, MPs from PB sample were characterized by a much higher content of Zn and Cu in comparison with MG sample. Cu is known as one of the most toxic metal for a large range of invertebrate marine species including early life stage of the bivalve Crassostrea gigas (Mai et al., 2012), the sea urchin Paracentrotus lividus (Fernández and Beiras, 2001) and the polychaete Hydroides elegans (Gopalakrishnan et al., 2007). Cu and other metals could be, at least in part, involved in the toxicity of the MPs leachates. ...
Microplastics are ubiquitous in aquatic ecosystems, but little information is currently available on the dangers and risks to living organisms. In order to assess the ecotoxicity of environmental microplastics (MPs), samples were collected from the beaches of two islands in the Guadeloupe archipelago, Petit-Bourg (PB) located on the main island of Guadeloupe and Marie-Galante (MG) on the second island of the archipelago. These samples have a similar polymer composition with mainly polyethylene (PE) and polypropylene (PP). However, these two samples are very dissimilar with regard to their contamination profile and their toxicity. MPs from MG contain more lead, cadmium and organochlorine compounds while those from PB have higher levels of copper, zinc and hydrocarbons. The leachates of these two samples of MPs induced sublethal effects on the growth of sea urchins and on the pulsation frequency of jellyfish ephyrae but not on the development of zebrafish embryos. The toxic effects are much more marked for samples from the PB site than those from the MG site. This work demonstrates that MPs can contain high levels of potentially bioavailable toxic substances that may represent a significant ecotoxicological risk, particularly for the early life stages of aquatic animals.
... On the contrary, both populations of F. enigmaticus showed higher sensitivity to mercury when compared with H. elegans (EC 50 : 9.33 μg/L). Regarding copper, Atlantic F. enigmaticus showed higher sensitivity if compared with H. elegans (exposed to 100 μg/L of Cu) (Gopalakrishnan et al., 2007). In particular, H. elegans had 40% well-developed larvae, while the percentage of F. enigmaticus from the Atlantic population, was only approximately 10% at the same concentration. ...
Previous studies suggested the suitability of the brackish-water serpulid (Ficopomatus enigmaticus) to be used as model organism for both marine and brackish waters monitoring, by the performance of sperm toxicity and larval development assays. The present study focused on larval development after the exposure of two F. enigmaticus populations (Mediterranean and Atlantic, collected in Italy and Portugal, respectively) to different trace elements (copper, mercury, arsenic, cadmium, and lead) at different concentrations. Results of larval development assays were presented as the percentage of abnormal developed larvae. The effect, measured in terms of EC50 for all toxicants tested, showed that mercury was the most toxic metal for larvae of both populations. Specifically, the tested trace elements may be racked in the following order from the highest to the lowest toxicity: Mediterranean: mercury > copper > lead > arsenic > cadmium; Atlantic: mercury > copper > cadmium > arsenic > lead. Responses of both populations were similar for arsenic. Lead was the least toxic element for the Atlantic population, while cadmium showed the least toxicity for the Mediterranean population. These preliminary results demonstrate the sensitivity and suitability of the organisms to be used in ecotoxicological bioassays and monitoring protocols. Moreover, chemical analyses on soft tissues and calcareous tubes of collected test organisms and their sampling site water were performed, to identify and quantify the concentration of the tested trace elements in these 3 matrices. Populations exhibited less sensitivity to a certain element together with a relevantly higher concentration of the same element in soft tissues. This may indicate a certain resistance to particular contaminant toxic effects by organisms that tend to accumulate the same toxicant. This highlights the potential correlation between wild-caught test organisms’ responses and a deep characterization of the sampling site to identify putative abnormalities or differences in model organism response during bioassay execution.
... The diversity and richness of meiofaunal taxa are generally lower in polluted and stressed environments, due to the loss of some sensitive taxa (e.g., copepods, polychaetes, ostracods, gastrotrichs and tardigrades; Lee et al., 2001;Lee and Correa, 2005;Gopalakrishnan et al., 2007;Giere, 2009;Wilson and Kakouli-Duarte, 2009). This tipically results in meiofaunal assemblages increasingly dominated by highly tolerant organisms, such as nematodes . ...
Portmán Bay is one of the most contaminated and chronically impacted coastal marine areas of the world. Here, from the 1957 to 1990, about 60 million tons of mine tailings from the processing of sulfide ores were dumped directly at the shoreline. The resulting deposit provides a unique opportunity to assess the impact of mine tailings on coastal marine ecosystems after ca 30 years since the discharge has ceased. We investigated meiofaunal abundance, biomass and biodiversity along a gradient of metal concentration that overlaps with a bathymetric gradient from 30 to 60 m depth. Despite the localized presence of extremely high concentration of metals, the bay was not a biological desert, but, nevertheless, was characterized by evident signs of impact on benthic diversity. Meiofaunal variables increased significantly with decreasing metal contamination, eventually reaching values comparable to other uncontaminated coastal sediments. Our results show that mine tailings influenced the spatial distribution of meiofaunal taxa and nematode species composition. In particular, we report here that the bay was characterized by the dominance of nematode opportunistic species tolerant to high metal concentration. The effects of mine tailing discharge on meiofaunal biodiversity and composition were still evident ca 30 years after the end of the mining activities. Overall, this study provides new insights on the potential impact of mine tailings disposal and metal contamination in coastal sediments, and, can also contribute to predict the potential long-term consequences of ever-expanding deep-sea mining industry on benthic environments.
... Durante este periodo los organismos se alimentaron mediante la adición semanal de 0.5 g de alimento artificial seco que consistía en una mezcla, a partes iguales, de espinaca y comida para peces (Méndez, 2006a,b). Posteriormente, permanecieron tres días en agua de mar sin sustrato (Gopalakrishnan, Thilagam, & Raja, 2007). ...
Introducción:
Diversos estudios han demostrado el efecto del Cd sobre la mortalidad y otras respuestas fisiológicas de diversas especies de poliquetos.
Objetivo:
Evaluar el efecto tóxico del Cd en la mortalidad de adultos de Polydora sp. como especie prueba para estudios ecotoxicológicos.
Métodos:
Los especímenes fueron recolectados en el humedal costero Poza de la Arenilla, Callao, Peru. Los organismos fueron aclimatados durante dos semanas con agua de mar y sedimento y posteriormente, tres días en agua de mar, con 30 ‰ de salinidad y temperatura entre 20 a 22 °C. Los organismos se expusieron a las concentraciones nominales 75, 11.25, 1.69, 0.25; 0.04 mg/L de Cd y un control. Se analizaron tres réplicas de diez individuos por tratamiento durante 72 horas para registrar mortalidad. Se aplicaron las pruebas de Kruskal-Wallis y de U-Man Whitney para detectar las diferencias significativas entre tratamientos.
Resultados:
El efecto adverso del Cd sobre la mortalidad fue mucho más evidente en los tratamientos de 11.25 y 75 mg/L a partir de las primeras 24 horas de exposición. La concentración letal media de Cd a 72h fue de 2.59 mg/L.
Conclusiones:
La CL50 está en el mismo orden de magnitud de otras especies de poliquetos. Este es el primer estudio ecotoxicológico en Perú con poliquetos en condiciones de laboratorio. Se sugiere la utilización de Polydora sp. como especie prueba en experimentos de ecotoxicología, utilizando concentraciones nominales subletales de Cd que no superen los 1.6 mg/L para la observación de varias respuestas fisiológicas.
... Lewis et al., 2013Lewis et al., , 2016Siddiqui and Bielmyer-Fraser, 2015). However, these altered toxicity responses under OA conditions reported across studies vary in magnitude according to both species and life history stage, and are not consistent across the different endpoints measured, suggesting that the observed altered toxicity is not simply being driven by the change in metal speciation but that physiology also plays a role (Campbell et al., 2014;Gopalakrishnan et al., 2007;Lewis et al., 2016;Scanes et al., 2018). Since most contaminants, including copper, accumulate in sediments and concentrations of heavy metals in sediments usually exceed those of the overlying water by between 3-5 orders of magnitude (Bryan and Langston, 1992) sediment dwelling organisms are often exposed to the highest levels of any contaminant. ...
... The results obtained from the F. enigmaticus larval development assay performed on environmental samples seem to agree with other serpulid polychaete species, like Hydroides elegans (Xie et al., 2005;Wong et al., 2006;Qiu et al., 2007;Gopalakrishnan et al., 2007Gopalakrishnan et al., , 2008Lau et al., 2007;Thilagam et al., 2008) and Serpula vermicularis (Gray, 1976), in terms of feasibility and ecological relevance. As defined by Rand et al. (1995), the relevance of a laboratory toxicity test species needs two requirements: sensitiveness and environmental relevance. ...
Ficopomatus enigmaticus is a serpulid polychaete, reef-forming, dioecious gamete spawner throughout different seasons and in different salinity conditions. Due to these characteristics, its candidacy as a model organism to monitor both marine and brackish matrices was assessed. Marine sediments collected in a polluted area near the port of Ancona (Italy) were used as case study. Besides the chemical characterization of sediments, the larval development of F. enigmaticus was adopted as an assay for ecotoxicological assessment of sediments in addition to a regulatory bioassay battery with different organisms and endpoints. The quality of sediments was classified according to the Italian Ministerial Decree for sediment management (Ministerial Decree 173, 2016) by using the SEDI-QUAL-SOFT® (ver. 109.0) software developed by the Italian Environmental Protection Agency (ISPRA). The F. enigmaticus larval development assay showed a quite similar sensitivity to C. gigas larval development assays, indicating its potential use in a regulatory battery of bioassays.
... Accidental industrial spills may lead to high concentrations of metal compounds in water, which have both acute and chronic toxic effects on aquatic organisms. Because these heavy metals do not degrade and thus accumulate in ecosystems, their toxic effects may be found at the molecular, cellular, and histological levels, even impacting homeostasis in organisms [3,4]. Individual components of heavy metals have been reported by different authors to have varying toxicological effects on aquatic organisms, and deaths of animals have also been reported at various concentrations [5]. ...
... No biofoulers were found on the copper plate, demonstrating the strong antifouling effects of copper in an urban tidal river (Fig. 5). Although aluminum is toxic to sedentary polychaetes (Gopalakrishnan et al. 2007), freshwater bivalves (Kadar et al. 2001) and bacteria (Kawakami et al. 2008), we found that aluminum had no antifouling effects on the golden mussel. The toxicity of aluminum likely depends on the target organism and it may have less effect on attached bivalves. ...
The golden mussel, Limnoperna fortunei, is native to South China but has spread to Japanese freshwater environments as a nuisance invasive species. The golden mussel colonizes hard manmade substrates and its attachment can cause economic losses at water intake facilities. To evaluate the repellent effects of the high alkalinity (pH 12–13) of freshly prepared cement mortar on golden mussels, test pieces made of cement were immersed in a Japanese urban tidal river. Compared with coated mortar, and wood and limestone test pieces, the cement mortar did not show significant repellent effects on golden mussel attachment. Therefore, concrete constructions on riverbanks may be a preferred substrate for golden mussel colonization. A 4-year immersion experiment showed that copper substrate had a strong repellent effect on biofouling, while cement mortar, aluminum, and stainless steel did not have any adverse effects on golden mussel attachment. This experiment also revealed the settlement of invasive golden mussel in an urban tidal area where the salinity fluctuated up to 20.0‰.
... Heart rate gener- Fig. 2. Species sensitivity distribution for benthic species found in New England, including both the native Aplidium glabrum and the invasive Botrylloides violaceus acute median effective concentration for settlement inhibition (EC 50 ) values for morphological effects due to copper exposure. Species are grouped by phyla accordingly: Annelida = purple diamond (Gopalakrishnan et al. 2007); Chordata = green squares (Bellas et al. 2005a); Mollusca = blue triangles (Calabrese et al. 1977, Rivera-Duarte et al. 2005, Arnold et al. 2009, Nadella et al. 2009); Echinodermata = pink circles (Rivera-Duarte et al. 2005); Arthropoda = black cross (Qiu et al. 2005 ally declined for A. glabrum, but at a slower rate than that of B. violaceus. ...
Colonial ascidians are a group of prolific invaders found in urban marine environments. Despite often high levels of pollution in these areas, some species of ascidians not only tolerate but thrive in these conditions, while native species decline. The role of pollution tolerance in establishment success is often overlooked, and therefore the mechanisms employed by invaders are poorly understood. This research explores both acute and chronic copper toxicity of Botrylloides violaceus, a prominent invader in the Gulf of Maine, and a native counterpart, Aplidium glabrum. Acute toxicity tests revealed that B. violaceus larvae are significantly more tolerant to exposure than A. glabrum larvae (median effective concentration for settlement inhibition [EC50] values = 107.9 and 46.7 µg l⁻¹, respectively). Further, the results indicate that B. violaceus is more tolerant than members of several other native benthic phyla using a species sensitivity distribution approach. Chronic toxicity tests determined that EC50 values impacting the number of zooids per colony and colony area for A. glabrum were achieved at environmentally relevant concentrations of copper, while B. violaceus values were over twice the concentration (approximately 8 and 20 µg l⁻¹, respectively). These findings support the hypothesis that invader pollution tolerance is indeed greater than that of native species, both within and beyond the same phyla, and likely plays a role in invader establishment and spread as described in the invader tolerance model.
... Earlier studies on toxicity of H. elegans showed the EC 50 values for Pb, Ni, and Zn for the first cell division and for the formation of fertilization membrane (FM stage) were 30.37, 38.30, and 44.22 mg l −1 , respectively, when the gametes were mixed together in the toxicant (Gopalakrishnan, Thilagam, & Raja, 2007). Moreover, exposure of gametes before fertilization decrease the fertilization rate in H. elegans, and thus, indicating the fertilization membrane formed may prevent the toxicants entering into the oocytes (Gopalakrishnan et al., 2008). ...
Background
The silver nanoparticles (AgNPs) are used in the production of numerous commercial and medical products and are found to have adverse effects on animals. The sessile marine polychaete worm, Hydroides elegans, was examined for the influence of AgNPs on external fertilization and early developmental stages. ResultsToxicity of AgNPs at various concentrations were examined on germ cells, fertilization rate, and early developmental stages. The EC50 was evaluated as 3 nM AgNPs; however, the survivability varied at each developmental stage, reducing with increasing stages of development, indicating a bioaccumulation effect of AgNPs. The lag in time of development suggested an impediment in dividing cells and the nuclear dysfunction assessed by DNA damage using comet assay. Conclusion
The observations documented have provided an insight on hazardous effect of AgNPs on susceptible cells and reproductive efficiency on other organisms including human.
... The manner in which gametes are exposed to the toxicant can affect their sensitivity and this is exemplified by experiments conducted by Gopalakrishnan et al. (2007Gopalakrishnan et al. ( , 2008. Gametes of the polychaete H. elegans varied remarkably in their sensitivity to trace metals depending on whether they were exposed during or prefertilization. ...
Significant amounts of trace metals have been released into both nearshore and deep sea environments in recent years, resulting in increased concentrations that can be toxic to marine organisms. Trace metals can negatively affect external fertilization processes in marine broadcast spawners and may cause a reduction in fertilization success at elevated concentrations. Due to its sensitivity and ecological importance, fertilization success has been widely used as a toxicity endpoint in ecotoxicological testing, which is an important method of evaluating the toxicity of contaminants for management planning. Ecotoxicological data regarding fertilization success are available across the major marine phyla, but there remain uncertainties that impair our ability to confidently interpret and analyse these data. At present, the cellular and biochemical events underlying trace metal toxicity in external fertilization are not known. Metal behavior and speciation play an important role in bioavailability and toxicity but are often overlooked, and disparities in experimental designs between studies limit the degree to which results can be synthesised and compared to those of other relevant species. We reviewed all available literature covering cellular toxicity mechanisms, metal toxicities and speciation, and differences in methodologies between studies. We conclude that the concept of metal toxicity should be approached in a more holistic manner that involves elucidating toxicity mechanisms, improving the understanding of metal behavior and speciation on bioavailability and toxicity, and standardizing the fertilization assay methods among different groups of organisms. We identify opportunities to improve the fertilization assay that will allow robust critical and comparative analysis between species and their sensitivities to trace metals during external fertilization, and enable data to be more readily extrapolated to field conditions.
... Accidental industrial spills may lead to high concentrations of metal compounds in water, which have both acute and chronic toxic effects on aquatic organisms. Because these heavy metals do not degrade and thus accumulate in ecosystems, their toxic effects may be found at the molecular, cellular, and histological levels, even impacting homeostasis in organisms [3,4]. Individual components of heavy metals have been reported by different authors to have varying toxicological effects on aquatic organisms, and deaths of animals have also been reported at various concentrations [5]. ...
Background
Acute toxicity testing were carried out the freshwater swamp shrimp, Macrobrachium nipponense, as the model animal for the semiconductor applied metals (gallium, antimony, indium, cadmium, and copper) to evaluate if the species is an suitable experimental animal of pollution in aquatic ecosystem.
Results
The static renewal test method of acute lethal concentrations determination was used, and water temperature was maintained at 24.0 ± 0.5°C. Data of individual metal obtained from acute toxicity tests were determined using probit analysis method. The median lethal concentration (96-h LC50) of gallium, antimony, indium, cadmium, and copper for M. nipponense were estimated as 2.7742, 1.9626, 6.8938, 0.0539, and 0.0313 mg/L, respectively.
Conclusions
Comparing the toxicity tolerance of M. nipponense with other species which exposed to these metals, it is obviously that the M. nipponense is more sensitive than that of various other aquatic animals.
... Additionally they found that larval development of this polychaete was more sensitive to the effluent of a lead smelting plant than two species of microalgae as well as the gametes of the bivalve mollusc Mytilus edulis Linneaus 1758 and could act as a sensitive bioindicator of mixtures of pollutants in the field. Gopalakrishnan et al. (2007) studied the effects of several heavy metals on fertilization, embryogenesis and larval development of H. elegans in laboratory culture and found that larval development and embryogenesis were the most sensitive stages. The developmental stages of H. elegans were ranked in their sensitivity to the metals tested in the following order: Cu>Al>Pb>Ni>Zn. ...
Polychaetes are usually the most abundant taxon in benthic communities and have been most often utilized as indicator species of environmental conditions. This review finds that, while the use of indicator spe- cies for a particular pollutant is not simple, polychaetes can provide a useful means of assessing the effects of poor environmental conditions. Polychaetes may be used as sensitive monitors of water quality especially in terms of the effects of pollutants on life history characteristics. They may also be utilized as general indicators of community diversity but those species indicative of lower diversity may differ geographically and tempo- rally. While sewage is often a mixture of high organic material and other pollutants such as heavy metals and pesticides, high organic situations associated with aquaculture facilities indicates that members of the Capitella capitata species complex and the dorvilleid genus Ophryotrocha are often dominant. Some species of poly- chaetes are able to live in sediments very high in trace metal content and body burden of these metals often does not reflect sediment concentrations due to regulation by these species. Many species seem relatively resistant to organic contaminants and pesticides and the effects of these pollutants on life history characteristics of these species may provide a more sensitive assay method. Recent studies using biomarkers in polychaetes to indicate general heavy metal or pesticide contamination has shown some success. Polychaete species known to occur in appreciable densities in the Gulf of Nicoya, Costa Rica, and which have been most often used as indicator species of pollution, are listed as potential taxa for environmental monitoring in this tropical estuary. Rev. Biol. Trop. 56 (Suppl. 4): 11-38. Epub 2009 June 30.
... At all concentrations, Zn ions and ZnO compounds exerted only a barely observable toxicity. This difference in sensitivity between the two systems, was previously evidenced in marine invertebrate [41][42][43][44] and could be addressed to a higher resistance to toxic chemicals evidenced by sperms. In addition, the high cell differentiation and the short exposure to the toxic substances foreseen in the procedure may contribute to this lack of sensitivity. ...
... In 2011, the Italian Ministry of the Environment and Territory and Sea Protection announced that the UNICHIM pr MU 2365 method was approved for use, among other toxicological bioassays, for acceptability evaluation of dispersant/adsorbant products to be used for remediation of petrol hydrocarbon pollution in marine environments.Table 6. Nickel toxicity to brackish/marine invertebrate species Taxonomic group Species Endpoint Concentration (mg Ni/L) Reference Mollusks Crassostrea virginica 48-h LC50 (embryos) 1.18 [29] 12-d LC50 (larvae) 12.0 Haliotis rufescens 48-h EC50 (larval development) 0.146 [30] 22-d EC50 (larval development) 0.026 Mercenaria mercenaria 48-h LC50 (embryos) 0.310 [29] 8–10-d LC50 (larvae) 5.7 Arthropods Apocyclops borneoensis 48-h LC50 13.1 [31] Americamysis (Mysidopsis) bahia 96-h LC50 0.508 [32] Hyalella azteca 96-h LC50 0.890 [33] Mysidopsis bigelowi 96-h LC50 0.56–0.640 [29] Mysidopsis formosa 96-h LC50 0.150 [29] Mysidopsis intii 96-h LC50 0.149 [30] 28-d LC50 0.022 Nitocra spinipes 96-h LC50 6.0 [29] Tigriopus japonicus 48-h LC50 17.7 [31] Annelids Hydroides elegans 24-h EC50 (larval development) 0.274 [34] Neanthes arenaceodentata 10-d LC50 16.1 [35] Nereis diversicolor 96–168-h LC50 25.0 [29] EC50 ¼ effective concentration, 50%; LC50 ¼ median lethal concentration. ...
The availability of standardized protocols for both organism culture and bioassay with ecologically relevant species is of great concern in ecotoxicology. Acartia tonsa represents an important, often dominant, member of zooplankton communities and meets all the practical criteria suggested for model species. New standardized procedures for laboratory culturing of the copepod A. tonsa and standardized methods for acute (24- and 48-h) and semichronic (7-d, static-renewal) toxicity tests with the nauplius stage are described. In both cases, eggs are the starting stage, and nauplius immobilization is the endpoint. The methods were the object of an intercomparison test involving nine laboratories, and nickel was the reference toxicant. Relative reproducibility was 24, 25, and 34% for 24-h, 48-h, and 7-d tests, respectively.
... These high concentrations may be responsible for shifting food webs and hence changing ecosystem processes. A reason for these changes probably is the toxicity of metals and metalloids on water organisms and the possible enrichment in the food web (Alves et al. 2009; Borgmann et al. 2005; Gopalakrishnan et al. 2007). Gammarus pulex L., used in this investigation as sample species, is an important food base for fish (Winkelmann et al. 2007) and a key species for processing of leaf litter in freshwater ecosystems (Robinson et al. 1998). ...
Many studies were conducted measuring the lethal concentration of pollutants by using a contaminated solution or polluted
sediments. Considering the impact of polluted food on mortality and uptake quantity of invertebrate shredders in batch cultures,
little is known about, e.g. uranium and cadmium. Consequently, we investigated in situ the impact of metal and metalloid polluted
food and water on Gammarus pulex L. under nature-like conditions. In contrast to other publications, a very low mortality rate of the invertebrates was found.
Furthermore, fixation of elements by G. pulex was shown to be low compared to initial concentrations. Fixation of non essential metals and metalloids is shown to take
place mainly on the surface of the invertebrates. This is deduced from easy desorption of a relevant amount of fixed metals
and metalloids. It is concluded that the accumulation of metals and metalloids in situ under nature-like conditions within
the food web via invertebrate shredders is very low. The invertebrates seem to minimize the uptake of non essential elements
in the presence of nutrient-rich food even in habitats with higher contamination levels. Hence, invertebrates seem to be adapted
to higher contamination levels in their favourable habitats.
KeywordsFixation–Avoidance–Invertebrates–Leaf litter–Chemical speciation–Desorption kinetics
... Several polychaetes have been used as biomonitors for toxicological studies because they are deposit-feeders, have sensitivity and resistance to contaminants, and are relatively easy to collect, handle, culture, and transport (Scaps, 2002;King et al., 2004;Casado-Martínez et al., 2008). Moreover, polychaetes have a relatively short generation time that makes them ideal organisms for studying the effects of toxicants on differently developed stages (Mauri et al., 2003;Lau et al., 2007;Gopalakrishnan et al., 2007;. ...
The infaunal polychaete Perinereis aibuhitensis Grube, distributed widely along Asian coasts and estuaries, is considered a useful animal model in ecotoxicological tests
and a promising candidate in biomonitoring programs. This paper deals with the activities of antioxidant enzymes including
superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidases (GSH-Px) in infaunal polychaete P. aibuhitensis exposed to a series of sublethal water-bound cadmium (Cd) concentrations (0, 0.34, 1.72, 3.44, 6.89, and 17.22 mg L−1) under a short-term exposure (1–8 d). The results indicate that the SOD and GSH-Px activities in P. aibuhitensis are stimulated first and then renewed to the original level. The CAT activity of worms decreases at an earlier exposure time
but increases to the control values at a later exposure time. Our study suggests that Cd can interfere with the antioxidant
defense system of P. aibuhitensis. However, the changes in antioxidant enzyme activities for this species do not show the best promise as biomarkers in Cd
biomonitoring of estuarine and coastal zones because weak or non-dose-effect relationships between the antioxidant enzymes
activities and Cd levels are found.
KeywordPolychaete (Perinereis aibuhitensis)-cadmium-antioxidant enzyme-biomarker-biomonitoring
... À1 Gopalakrishnan et al., 2007, 2008 ...
In the last 15 years the diversity of pollutants and routes of impact have increased. However, the polychaete families, species and endpoints investigated have remained fairly constant. Reproductive outputs are more ecologically relevant than adult physiological or biochemical changes. Nevertheless, there remains a paucity of data on the reproductive responses of the popular species to pollutants which limits our ability to understand the true ecological impacts of such contaminants on natural populations. We highlight the current knowledge gaps in our understanding of the impacts of pollutants on the 'model' species' reproductive biology and therefore the potential ecological impacts of such contaminants on their natural populations, and the potential benefits of a wider use of polychaete reproductive endpoints for ecotoxicological assessments. The following priority areas are suggested for inclusion in the polychaete ecotoxicology toolbox: 1. Include reproductive endpoints as assessments of ecotoxicology for the traditional 'model' species and those that have different reproductive traits to ensure broad ecological relevance. 2. Nereids and Arenicola marina should be used to investigate the interaction of pollutants with the endocrine/environmental control of reproduction. 3. Polychaetes are ideal for addressing the under representation of male eco-toxicity effects. 4. Emerging pollutants should be assessed with reproductive endpoints together with the traditional biomarkers. 5. Effects of pollutants on larval behaviour need to be explored considering the limited but equivocal results so far.
Heavy metals are considered important toxic pollutants that enter the biogeochemical circuits and accumulate in natural and artificial ecosystems, including in the Black Sea ecosystem. Heavy metals are continuously released into the biosphere by volcanic eruptions and natural weathering of rocks, but also by numerous anthropogenic activities such as mining, burning fossil fuels, industrial and urban wastewater, and agricultural practices. On a global scale, there is now evidence that anthropogenic activities have polluted the environment with heavy metals from the poles to the tropics and from the mountains to the depths of the oceans.
Oyster Crassostrea gigas, is considered as a useful environmental indicator since it is widely distributed along the intertidal zone whereby it tends to accumulate cadmium and is always exposed to various pathogen agents. However, its molecular responses to both cadmium and pathogen stimulation remain unclear. In the present study, transcriptome data of hemocytes from oysters were analyzed to reveal specific molecular responses of oyster to cadmium or cadmium/bacteria stimulation. A total of 21591, 22872 and 20107 genes were detected in the BLANK, Cd24h and Cd/Bac24h group, respectively. Among them, there were 685 differentially expressed genes collected in the comparison of Cd24h versus BLANK. GO analysis of these genes found that sixteen terms into the Molecular Function category displayed transporter activities, and were all over-enrichment by cadmium exposure, whereas twelve terms into Biological Process category involved mainly in metabolic process of the various cellular components and two terms into Cellular Component category were all under-enrichment. The 330 immune responsive genes were shared by two gene lists of CdBac24h versus BLANK and CdBac24h versus Cd24h, and seven out of thirty terms in GO analysis were related to the immune process. Further annotation of these genes from the KEGG database revealed fourteen pathways, including two nervous system related pathways, arachidonic acid pathway, four immune pathways, MAPK cascade and other four cell signaling pathways, and two energy related pathways. Twenty-two differentially expressed genes were identified to responsive to both cadmium exposure and bacteria stimulation, but in different expression patterns, suggesting that bilateral responsive genes, such as alkaline phosphatase and sodium and chloride-dependent glycine transporter gene, could be candidate biomarkers for early warming of cadmium pollution. The present results collectively indicated that a profound neuro-endocrine-immune regulatory network was activated in response to cadmium and bacteria stimulation in oyster C. gigas, and the expression pattern of some cadmium responsive genes may be either reversed or strengthened by bacteria stimulation. The results provide knowledge on the transcriptomic response profile of oyster after short-term cadmium exposure and bacteria stimulation, which would be useful for future studies on stress response mechanism of mollusc, and some cadmium-bacteria responsive genes may be explored as potential biomarkers for monitoring marine pollution.
Elevated concentrations of metals have been reported in the marine environment globally where they have the capacity to be toxic to marine organisms. Of concern are the fertilisation and early development of marine invertebrates which are vulnerable to metal toxicity. Scientific and technological advances have enabled the development of numerous rapid, accurate, and semi-autonomous methods for the assessment of sperm. Consequently, sperm parameters are being recommended as rapid alternative endpoints to fertilisation success. For these parameters to be used as endpoints in water quality guideline derivation, ecological relevance needs to be demonstrated via a proven adverse outcome pathway (AOP). This research assessed the effects of metals (Cu, Zn, Cd and Pb) to fertilisation success in the marine invertebrate Galeolaria caepitosa and found that the primary cause of toxicity was through effects on sperm. When the impact of a toxicant is to sperm, current protocols for fertilisation assays could underestimate toxicity. This study found up to three-fold differences in toxicity estimates at sperm densities that all yield >80% fertilisation in controls. More appropriate toxicity estimates would be achieved by assessing toxicity using low sperm densities, for example, those which achieve only 50% fertilisation success. Alternatively, sperm endpoints could be used to provide sensitive (and conservative) toxicity estimates, provided an AOP has been established. For Cu, effects on sperm motility (%) could account for the effects of metals on fertilisation success, and thus can be used as an indicator of Cu toxicity. For Zn, effects on the ability for sperm to undergo the acrosome reaction can be used as a rapid indicator of effects to fertilisation success. However, For Cd and Pb, effects on fertilisation could not be appropriately represented by any of the sperm endpoints tested here. This research highlights the importance of understanding the mechanism of toxicity to fertilisation success and provides recommendations for future ecotoxicological assessments.
In marine animals with external fertilization, gametes are released into seawater where fertilization and embryo development occur. Consequently, pollutants introduced into the marine environment by human activities may affect gametes and embryos. These xenobiotics can alter cell physiology with consequent reduction of fertilization success. Here the adverse effects on the reproductive processes of the marine invertebrate Ciona intestinalis (ascidian) of different xenobiotics: lead, zinc, an organic tin compound and a phenylurea herbicide were evaluated. By using the electrophysiological technique of whole-cell voltage clamping, the effects of these compounds on the mature oocyte plasma membrane electrical properties and the electrical events of fertilization were tested by calculating the concentration that induced 50% normal larval formation (EC 50 ). The results demonstrated that sodium currents in mature oocytes were reduced in a concentration-dependent manner by all tested xenobiotics, with the lowest EC 50 value for lead. In contrast, fertilization current frequencies were differently affected by zinc and organic tin compound. Toxicity tests on gametes demonstrated that sperm fertilizing capability and fertilization oocyte competence were not altered by xenobiotics, whereas fertilization was inhibited in zinc solution and underwent a reduction in organic tin compound solution (EC 50 value of 1.7 µM). Furthermore, fertilized oocytes resulted in a low percentage of normal larvae with an EC 50 value of 0.90 µM. This study shows that reproductive processes of ascidians are highly sensitive to xenobiotics suggesting that they may be considered a reliable biomarker and that ascidians are suitable model organisms to assess marine environmental quality.
Cytological responses in different organs of sentinel organisms have proven to be useful tools for characterizing the health status of those organisms and assessing the impact of environmental contaminants. Our study shows that nickel (II) accumulated in both germ cells (oogonia and developing oocytes) and somatic cells (muscle cells, follicle cells) in the Astacus leptodactylus ovary. Muscle cells from ovarian wall show disorganization and the disruption of cytoplasmic microtubules and pyknosis of the cell nucleus. Follicle cells, both those that surround the developing oocytes and also those that are not associated with the oocytes contained within the cytoplasm vacuoles of different sizes, degenerated mitochondria, myelin bodies, disorganized microtubules, and pyknotic nuclei. The most evident pathological phenomenon was the alteration and disorganization of the basal matrix, which separates the ovarian interstitium from ovarian follicles compartment. Exposure to nickel induces cytoplasmic vacuolation in oogonia and developing oocytes, structural alteration of the developing yolk granules and condensation of the nucleoli. Ultrastructural autometallography has shown grains of silver-enhanced nickel inside the cytoplasm of the muscle cells with altered morphology, including the cytoplasm, nucleus, and basal matrix of the follicle cells, and in intracisternal granules and developing yolk granules of the oocytes.
The demand for nickel and cobalt as important commodities has increased significantly over the past decade and a decline in the global nickel sulphide reserves has resulted in a shift toward the exploitation of the less favourable nickel laterite ores. These deposits, which are found associated with cobalt, are located predominantly in the tropical regions of the world where there is limited understanding of the toxicities of their extracted products and wastes. This study investigated the effects of nickel, cobalt and combinations of nickel and cobalt on the fertilization success of the common and widespread scleractinian coral Platygyra daedalea. We also present the first assessment of the effect of copper on fertilization success of this species. The EC50 value for copper was 33 μg L(-1) (95% confidence limits: 30-37 μg L(-1)) and is consistent with published values for other coral species. Our results provide the first EC50 value for the effect of nickel on fertilization success in a scleractinian coral, with an estimated value of 1420 μg L(-1) (95% confidence limits: 1160-1780 μg L(-1)). Concentrations of cobalt as high as 2500 μg L(-1) did not significantly reduce fertilization success nor did combinations of nickel (500 μg L(-1)) and cobalt (up to 1000 μg L(-1)). These are important findings given the emerging nickel-cobalt mining industry in the tropics and provide much needed toxicity data regarding the early-life histories of ecologically relevant tropical marine species.
This study investigated the effects of increasing mercury (Hg) concentration on early
developmental stages of sea urchin, Echinomethra mathaei, as a bioindicator. The toxicity test
was carried out after the gamete released induction and fertilization in six concentrations of
mercury within the range of 4, 8, 16, 32, 64 and 128 μg/L. Embryos samples were incubated
for 30 h in control and test solutions. After incubation, the percentage of developed 4-arm
pluteus larvae was recorded in each group and embryonic abnormalities were studied by a
microscope. Results of this study indicate that exposure of embryos to increasing mercury
concentrations lead to abnormalities such as changes to shape and size of pluteus larval arms
and also arrested development in early embryonic stages. Furthermore, embryos were
analyzed to determine mercury absorption by cold vapour atomic absorption spectrometry
method (AAS). The median effective concentration (EC50) value calculated for mercury was
17/42 μg/L.
Each book has two main goals 1. Determine baseline concentrations of metals and metalloids in tissues of representative field populations of estuarine coastal, and open ocean organisms (Book 1:algae and macrophytes, protists, sponges, coelenterates, molluscs, crustaceans, insects, chaetognaths, annelids, echinoderms, and tunicates) (Book 2: elasmobranchs, fishes, reptiles, birds, mammals) and their significance to organism health and to the health of their consumers. 2. Synthesize existing information on biological, chemical, and physical factors known to modify uptake, retention, and translocation of each element under field and laboratory conditions. Recognition of the importance of these modifiers and their accompanying interactions is essential to the understanding of metals kinetics in marine systems and to the interpretation of baseline residue data. Synthesizes existing information on biological, chemical, and physical factors known to modify uptake, retention, and translocation of each element Aids understanding of metals kinetics in marine systems Allows the interpretation of baseline residue data.
In this work, A weak acid cation exchange textile (CET) was prepared by 60Co γ-rays irradiation grafting with acrylic acid (AA) onto polypropylene (PP) non-woven (PP-g-AA). The feasibility of PP-g-AA as ion exchanger for enrichment and removal of four heavy metal ions (Cu(II), Zn(II), Cd(II), Pb(II)) in seawater was investigated. The exchange capacity of CET with the grafting degree of 45% is 3.7 mmol/g. The results indicated that the PP-g-AA CET could efficiently absorb the Cu(II), Zn(II), Cd(II), Pb(II) metal ions although there are large amount of Na(I), K(I), Mg(II), Ca(II) ions existing in seawater. The CET in Na+ form (PP-g-AA being deal with NaOH) was better for the enrichment of these four metals than CET in H+ form. The dynamic adsorption for metal ions by CET was superior to the static adsorption. Metal ions retained on CET could be desorpted with 1mol/L HNO3. All the results indicated that carboxylic acid cation exchange polypropylene textile had great potential for the enrichment and removal of heavy metals in seawater.
Data on Serpulidae collected in the Suez Canal were assembled and analyzed. Five serpulid taxa are reported from the canal for the first time bringing the number of serpulids to at least 16. The Systematic Section compiles revised literature records, confirmed synonymies of the taxa, redescriptions where necessary, photographic studies of taxa and remarks on the populations studied. The possible Indo-West-Pacific or Mediterranean origins of the taxa in the Suez Canal are considered and their chronological records and distributions tracked within the Red Sea, the Gulfs of Aqaba and Suez, the Suez Canal and the Levant Basin based on the compiled literature and our extensive databases. Two Lessepsian migrants, Hydroides heterocerus and H. homoceros, show evidence of morphological variability along their migration route; the last also provides an example of a founder effect. Problems of identifying Protula and Salmacina taxa are addressed, along with remarks on the “cosmopolitan” designations of some taxa. Various hypotheses concerning Lessepsian migration are discussed, and attributes making Lessepsian migrant serpulid tubeworms successful invasive species are evaluated.
The purpose of this paper was to evaluate the capacity of anion ion exchange fiber to uptake the heavy metal(Co(2+), Cu(2+), Zn(2+), Cd(2+), Pb(2+), Ag(+)) from the water. A new polyamine-type ion exchange fiber(IEF) based on polyacrylonitrile (PAN) with higher exchange capacities was prepared by crosslinking through hydrazine hydrate, followed reacting with diethylene triamine. FT-IR analysis indicated that amine, imido, acylamino and carboxyl groups were introduced into PAN fiber through the surface modified reaction of cross linking and amination. The structures of the IEF were characterized by means of SEM. The results showed that the surface of fiber became rougher and thicker and more heterogeneous. The static and dynamic. adsorption experiments demonstrated the high selective adsorption property of the IEF for Ag(+) and Cu(2+). Furthermore, the adsorption mechanism for the metal ions with IEF was investigated with the FT-IR spectra studies.
As the most widely used plasticizers in the world, phthalate esters (PAEs) are potential endocrine disruption compounds (EDCs).
In the present study, the toxicity of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl)
phthalate (DEHP) on embryogenesis and larvae development of the marine univalve Haliotis diversicolor supertexta was examined in laboratory. The results show that the malformation of embryos appeared during the experiment, such as embryos
died or lysed, small transparent flocculent rings studded on the periphery of the embryo, and the larvae could failed to hatch.
In embryo toxic test, embryos incubated at the highest concentration of DMP, DEP and DBP solutions showed significantly high
abnormal rate compared with the control, while DEHP solutions displayed no significant difference. In larval toxic test, in
all concentrations of DMP, DEP and DBP solutions, larval settlement rates were low significantly than that of the control.
Similarly, DEHP solutions show nearly no effect on the larval settlement. The order of toxicity on embryos and larvae is DBP>DEP>DMP>DEHP.
Being a simple and easy stimulation to indoor spawn, sensitive to environmental factors, and short culture time, the embryos
of H. diversicolor supertexta can be used to indicate toxicity of the PAEs.
Biomonitors are commonly used to assess levels of bioavailable contaminants in the environment, however the relationships between biomonitor tissue concentrations and ecological effects are rarely assessed. The present study investigated metal contamination within a highly industrialised harbour and ecological effects on sessile invertebrates. The native oyster Saccostrea glomerata was deployed as a biomonitor across twenty-six sites to test for correlations between metal levels in their tissues and the recruitment of hard-substrate invertebrates. Concentrations of lead and copper in oyster tissues were negatively correlated with densities of the dominant barnacle, Amphibalanus variegatus, and positively correlated with densities of the dominant polychaete, Hydroides elegans, and the two native encrusting bryozoans Celloporaria nodulosa and Arachnopusia unicornis. Results suggest that highly localised events drive contaminant availability and that these events pose a significant risk to fauna. Biomonitoring studies may be enhanced by running concurrent ecological surveys.
Acute toxicity tests revealed that, in red sea bream (Pagrus major) embryos, 24 and 48 h LC(50) values of waterborne HgCl(2) were 67.3 and 39.1 μg Hg(2+) L(-1). In larvae, 48, 72 and 96 h LC(50) values were 41.9, 36.1 and 34.8 μg Hg(2+) L(-1), respectively. Sub-chronic toxicity tests indicated that mercury concentrations ≥20 μg Hg(2+) L(-1) decreased hatching success, increased mortality and induced teratogenicity in embryos and larvae. The NOEC, LOEC and MATC values were 8.0, 16.3 and 11.4 μg Hg(2+) L(-1) for hatching success, mortality and teratogenicity; while those were 27.0, 36.9 and 31.6 μg Hg(2+) L(-1) for body length and specific growth rate, respectively.
The effects and associated toxicological mechanisms of five phthalate esters (PAEs) on abalone embryonic development were investigated by exposing the embryos to a range of PAEs concentrations (0.05, 0.2, 2 and 10 μg/mL). The results showed that PAEs could significantly reduce embryo hatchability, increase developmental malformations, and suppress the metamorphosis of abalone larvae. The possible toxicological mechanisms of PAEs to abalone embryos included, affecting the Na+-K+-pump and Ca2+-Mg2+-pump activities, altering the peroxidase (POD) level and the malondialdehyde (MDA) production, damaging the extraembryonic membranes structure, as well as disrupting endocrine-related genes (gpx, cyp3a, and 17β-hsd 12) expression properties. Taken together, this work showed that PAEs adversely affected the embryonic ontogeny of abalone. The abilities of PAEs affecting the osmoregulation, inducing oxidative stress, damaging embryo envelope structure, and causing physiological homeostasis disorder, are likely to be a part of the common mechanisms responsible for their embryonic toxicity.
Siriella armata (Crustacea, Mysidacea) is a component of the coastal zooplankton that lives in swarms in the shallow waters of the European neritic zone, from the North Sea to the Mediterranean. Juveniles of this species were examined as standard test organisms for use in marine acute toxicity tests. The effects of reference toxicants, three trace metals (Copper, Cadmium and Zinc), and one surfactant, sodium dodecyl sulfate (SDS) were studied on S. armata neonates (\24 h) reared in the laboratory. Acute toxicity tests were carried out with filtered sea water on individual chambers (microplate wells for metals or glass vials for SDS) incubated in an isothermal room at 20 degrees C, with 16 h light: 8 h dark photoperiod for 96 h. Each neonate was fed daily with 10-15 nauplii of Artemia salina. Acute (96 h) LC50 values, in increasing order, were 46.9 lg/L for Cu, 99.3 lg/L for Cd, 466.7 lg/L for Zn and 8.5 mg/L for SDS. The LC(10), NOEC and LOEC values were also calculated. Results were compared with Daphnia magna, a freshwater cladoceran widely used as a standard ecotoxicological test organism. Acute (48 h) LC(50) values were 56.2 lg/L for Cu, 571.5 lg/L for Cd, 1.3 mg/L for Zn and 27.3 mg/L for SDS. For all the reference toxicants studied, the marine mysid Siriella armata showed higher sensitivity than the freshwater model organism Daphnia magna, validating the use of Siriella mysids as model organisms in marine acute toxicity tests.
In contrast to the classification of most invertebrate shredders being sensitive to uranium, a G. pulex L. population with reproduction was found in a stream at a former uranium mining site with uranium concentrations of 150 microg l(-1) in water and up to 2000 mg kg(-1) DW(-1) (dry weight) in litter born organic sediments. The survival of G. pulex, collected from a site without uranium contamination, was tested in a laboratory microcosm experiment using synthetic uranium-contaminated water and uranium-contaminated but nutrient rich food, simulating physicochemical conditions of water from former uranium mining sites. The results reveal that there are no significant differences in survival rate between individuals exposed and those not exposed to uranium. The uptake of uranium by G. pulex in environments with concentrations in food of 1152 mg kg(-1) in DM (dry mass, organically bound) and in water of 63.9 microg L(-1) is very low (4.48(1.93-8.46) mg kg(-1) in DM). The accumulation of uranium in these invertebrates was verified to be via two pathways: body surface and food. A relevant amount of uranium adsorbs to the body surface where it can readily be desorbed.
Two experiments were performed to examine the sensitivity of Hydroides elegans to copper stress. The first experiment tested the development of 4 distinct early stages in copper solutions from 10 to 250 mug l(-1). Copper significantly reduced survivorship of the newly released oocyte and trochophore stages at concentrations greater than or equal to10 mug l(-1), and of the 2-cell and blastula stages at greater than or equal to25 mug l(-1). The EC50 values were 47, 50, 71 and 29 mug Cu l(-1) for the newly released oocytes, 2-cell embryos, blastulae and trochophores, respectively. After 2 h into the bioassay, where Isochrysis galbana was used as food for the trochophores, algal sorption resulted in a reduction in copper concentration from 32% in the 10 mug l(-1) treatment to 6% in the 250 mug l(-1) treatment. Duration of development did not significantly differ among the treatments, except in the oocyte to 2-cell stage where higher copper concentration resulted in longer developmental time. In the second experiment, adult H. elegans were exposed to copper concentrations from 125 to 4000 mug l(-1) for 48 h. Significant mortality occurred only at copper concentrations greater than or equal to500 mug l(-1). This study thus shows that the embryogenesis and larval development of H. elegans are sensitive to copper stress, and that algal sorption can substantially reduce soluble copper concentration and may affect the larval toxicity result.
Assessing the risk of effluents and other anthropogenic inputs to the receiving environment is ultimately best done on a site-specific basis, which often requires toxicity tests using organisms relevant to that environment. Additionally, the test species or life stage needs to be available for a reasonable portion of the year to allow temporal fluctuations to be assessed. A 48-h larval development toxicity test using the marine polychaete Galeolaria caespitosa was developed. This test was developed as G. caespitosa releases viable gametes year-round, and the test species is environmentally relevant to the marine system receiving the liquid effluent being evaluated. Toxicity tests were conducted using G. caespitosa from different locations and evaluating the gamete response to copper. All population responses were comparable, with EC50 values ranging from 16 to 40 microg/L copper (as CuCl2, x 2H2O). Toxicity tests were also conducted using G. caespitosa gametes with an effluent produced by a lead smelting operation. The response of the G. caespitosa test with this effluent was compared with three other test methods using two microalgal species, Isochrysis sp. and Nitzschia closterium, and gametes from the mussel Mytilus edulis. The G. caespitosa larval development toxicity test was the most sensitive test to the effluent, with EC50 values ranging from 1-23% effluent, while it ranked second in sensitivity to copper. This test could be applied to other common serpulids worldwide.
To document the impact of naphthalene, a comparative toxicological research was performed in the estuarine crab Scylla tranquebarica habitant of Ennore creek (polluted site) and Kovalam creek (pristine site) for a period of 6 months. The biochemical constituents, such as protein, carbohydrate, lipid and enzyme activities like acid and alkaline phosphatase, aspartate and alanine transaminase were analysed in hepatopancreas, heamolymph and ovary of the female crabs collected from the two creeks. The results revealed that there was a significant measurable difference in these parameters in the tissues of crabs sampled from the polyaromatic hydrocarbon (PAH) polluted site (Ennore creek) when compared with the reference site (Kovalam creek). In addition naphthalene was detected in gill, hepatopancrease, heamolymph and ovary of the crabs sampled from the polluted creek. The results indicate that the indicators selected for toxic impact in S. tranquebarica may be related to the uptake of naphthalene in the tissues examined and support the feasibility of employing these types of analyses as biochemical biomarkers for PAH contaminant-exposed organisms.
Description
This book offers the reader a series of case histories of actual use of complex test systems together with a discussion of their advantages and disadvantages. A substantial amount of information and methodology is provided that can be used in the validation process at the community level of biological organization.
A p H‐dependent model for the speciation of divalent Cu, Zn, Cd, and Pb ions in seawater was constructed with available and estimated thermodynamic stability constants and individual ion activity coefficients. This model was used to calculate the degree of interaction between each of the metal ions and the anions Cl ⁻ , SO 4 ²⁻ , HCO 3 ⁻ , CO 3 ²⁻ , and OH ⁻ as a function of p H. Interactions between a cation and an anion were assumed to result only in the formation of complexes with coordination numbers of 1 to 4; polynuclear and mixed‐ligand complexes were not included in the model.
The calculations showed the following: All four metals are complexed to a considerable extent in seawater; with the exception of Cd, the distributions of chemical species of the metals vary greatly with changes in pH; Cu interacts primarily with OH ⁻ and CO 3 ²⁻ , Zn with OH ⁻ , Pb with CO 3 ²⁻ and Cl ⁻ , and Cd with Cl ⁻ ; complexes with high coordination numbers (i.e. 3 and 4) are not formed to any appreciable extent in seawater.
Tens of thousands of synthetic substances are in existence today and hundreds of new compounds are being introduced every year. Because of the complexity of the physico-chemical interactions between pollutants and the marine environment, the potential toxicity of contaminants can be assessed adequately only by means of bioassays with living organisms. From a practical point of view, a bioassay needs to be sensitive and scientifically valid, yield rapid results at moderate cost, and the organism in question must be readily available. Ecotoxicological bioassays with bivalve embryos and larvae fitll these criteria better than most other tests. They have increasingly come into use during the past three decades and are now commonly employed to ascertain the biological effects of pure chemicals, as well as to determine the quality of effluents, coastal waters and sediments sampled in the field. There do not appear to be very great differences bet\veen bivalve species with regard to larval sensitivity to toxicants. The principal species for bioassays are oysters (Crassostrea gigas and C. virginica), and mussels (Mytilus edulis and M. galloprovincialis. Bioassays are conducted with gametes and larvae of all ages: sperm and unfertilized eggs, embryos, young D-larvae, intermediate umboned larvae, and pediveligers towards the end of the pelagic period. Embryos are usually the most sensitive stage. Recent advances now also permit bioassays on metamorphosing pediveligers, a method particularly suited to investigate the effects of adsorbate-contaminated surfaces. There are various criteria for the assessment of toxic effects, including embryogenesis success (abnormalities), larval growth, mortality, physiology (e.g. feeding or swimming activity), and metamorphosis success. Chronic toxicity studies may be carried out over periods of several weeks, but larval rearing in the laboratory requires considerable effort (e.g. ' cultivation of algal food). The method of choice for investigations of acute toxicity and for routine monitoring studies is the embryo bioassay because it is very sensitive, relatively simple, and produces results within 24 or 48 hours. The data obtained by different investigators are often difficult to compare, however, because of differences in methodology. There is no firmly established procedure, and further simplification and standardization of techniques is required. In bioassays with a single pollutant, the effective toxic concentration may span several orders of magnitude, depending on bioassay procedures, larval stage and choice of response. Tributyl-tin (TBT) is the most toxic compound ever bioassayed with bivalve larvae, with effective concentrations (EC50) as low as a few nanograms per litre (i.e. 10~3 ppb). Heavy metals (particularly mercury, silver and copper) are next in order of toxicity, with EC50 values between a few micrograms per litre (ppb) and several hundred ppb. Chlorine and some organochlorine pesticides may also have EC50 values of less than 100 ppb, while detergents and petroleum products are generally less toxic.
Larval behaviour in G. caespitosa is described from trochophore to settled juvenile. The trochophore swims, spiralling counterclockwise, with the apical tuft outstretched. Large cilia on the lips of the mouth assist in food intake. Two sphincter muscles control passage of food along the gut. By 4-5 days; the trochophore has circular, oblique, radial and longitudinal larval muscles. The radial muscles move the apical tuft. The other muscles brace the larval body and assist the passage of food through the gut. At 6-7 days the larva becomes demersal. Feeding and growth continue. At 8-9 days three pairs of setal sacs develop in rapid succession. Metamorphosis now takes place. beginning at 11 days with collapse of the prototroch. Tentacle buds and thoracic membrane rudiments develop even if settlement is not achieved. Other events of metamorphosis (collar evagination, tube secretion. tentacle growth and shrinkage of the head region) require prior settlement. Larval muscles play a part in the shape changes occurring during metamorphosis. Settlement conditions are complex and may include a response to light-coloured surfaces. Development to the three- setiger stage appears to be genetically preprogrammed. Metamorphosis and settlement must involve an interplay of several internal and external causal processes in a sequential manner.
The toxicity of copper, mercury and zinc to the larvae of oysters, shrimp, crab and lobsters has been examined over periods of up to 64 hours. Mercury was found to be more toxic than copper and zinc, which had similar levels of toxicity. Over the experimental period, the relationship between toxicity and concentration was linear. Larvae were from 14 to 1,000 times more susceptible than adults of the same species. The median lethal concentrations (LC50) of each metal to the most sensitive species of larvae, tested over a 48 hour period, exceeded the concentrations found in natural sea water by a factor of 100. For longer test periods, the LC50 would be considerably less and this factor would then be considerably reduced. Hence the continued addition of these metals to confined waters should give cause for concern.
Reproduction ofHeliocidaris erythrogramma (Valenciennes) andH. tuberculata (Lamarck) was compared through examination of oogenesis, spermatogenesis and monthly measurement of the gonad index. These species occur sympatrically in the Sydney region. Their reproduction was examined at two sites near Botany Bay, New South Wales, Australia, from February 1989 through January 1990.H. erythrogramma produces buoyant, 450µm-diam eggs and the sperm have a head region 10µm in length. By contrast,H. tuberculata produces negatively-buoyant, 95µm-diam eggs and the sperm have a head region 4µm in length. Histochemical examination of the gonads revealed that periodic acid Schiff-positive (PAS +) material stored in the nutritive phagocytes appears to support vitellogenesis in both species. InH. tuberculata this material is utilized in the formation of PAS + yolk oligolecithal eggs, whereas inH. erythrogramma the PAS + material appears to be converted to lipid yolk in macrolecithal eggs.H. erythrogramma had a seasonal reproductive pattern with a 3 mo summer spawning period, whereas both populations ofH. tuberculata had a 9 mo breeding period characterized by the continual presence of nutrient reserves and vitellogenic oocytes which rapidly replaced spawned ova. Spawning ceased only for 3 mo over the summer. Due to the 9 mo spawning ofH. tuberculata it is not clear what factors serve to cue reproduction in this species.
Low molecular weight, metal-binding proteins have been shown to occur in several marine invertebrate species. The molecular weights, metal contents, and induction of these proteins by metals such as cadmium, zinc, copper, and mercury suggest close similarities to metallothionein, a sulphydrl-rich, metal-binding protein of widespread occurrence in vertebrates. Metallothionein has, to date, been identified in two species of brachyuran crabs. The identity of the protein in other marine invertebrate groups such as molluscs is still to be determined. Continued study of the metal-binding proteins will undoubtedly contribute to our understanding of both the normal metabolism and toxicology of certain trace metals in marine species. It appears that these proteins may be involved in the sequestration and detoxification of metals. Organisms which have been exposed to metals such as cadmium, zinc, copper, or mercury in the laboratory or field exhibit enhanced levels of metals which are associated with the metal-binding proteins. Additional studies will be required in order to determine the biochemical and physiological significance of such bound metals.
Oxidizing agents of sulfhydryl groups such as iodosobenzoate, alkylating agents such as iodoacetamide, and mercaptide-forming
agents such as cadmium chloride, mercuric chloride, p-chloromercuribenzoate, sodium arsenite, and p-carboxyphenylarsine oxide, added in small concentrations to a suspension of sea urchin sperm produced an increase in respiration.
When the concentration was increased there was an inhibition. These effects are explained by postulating the presence in the
cells of two kinds of sulfhydryl groups: soluble sulfhydryl groups, which regulate cellular respiration, and fixed sulfhydryl groups, present in the protein moiety of enzymes. Small concentrations of sulfhydryl reagents combine only with the first, thus producing an increase in respiration; when the concentration is increased, the fixed sulfhydryl groups are also attacked
and inhibition of respiration is the consequence.
Other inhibitors of cell respiration, such as cyanide and urethanes, which do not combine with —SH groups, did not stimulate
respiration in small concentration.
Three rapid marine toxicity tests were evaluated to determine their potential usefulness in a toxicity testing program: early embryo growth test and sperm cell toxicity test, both using the sea urchin Arbacia punctulata , and Microtox. Toxicity values (EC50s) were derived for eight organic chemicals and five metals using each system. Results were compared with LC50 values for the same chemicals from standard aquatic tests with Pimephales romelas and Daphnia magna and for the metals with Menidia menidia and Mysidopsis bahia. The EC50 values for the sea urchin early embryo growth test for organics and the LC50 values for fish and crustaceans for organics and metals with which the rapid tests were compared were from the literature.
For organic chemicals, EC50s from rapid tests closely approximated LC50s and toxicity rankings, except that the sperm cell test was particularly sensitive to 2,4‐pentanedione and 2‐methyl‐2,4‐pentanediol. EC50s for metals were generally comparable with each other and with other tests using embryo and sperm of other sea urchins and oysters but not with LC50s for Mysidopsis and Menidia.
These results indicate the potential value of rapid tests to screen and rank substances for toxicity. Additional information on the usefulness of these tests will be gained through continuing comparisons using a broad spectrum of single substances and complex mixtures with varying modes of action.
Embryos of sea urchins show a differential response to Cd, Cu, Cr, Ni and Zn. The responses are also stage-specific. The different morphological effects of various metals reflect the differentiation of the early embryonic cells. Since fertilization can be inhibited in the presence of metals, especially Cu, the ability of the gametes to undergo fertilization can then be used as a biological indicator for a rapid assay, 10–20 min., of marine pollutants. Since embryo-genesis up to plutei stage requires only 20 h, this duration is also short compared to other systems utilizing embryonic or larval forms.
The toxicity studies of free 5-((E)-2-(aryl)-1-diazenyl)-2-hydroxybenzoic acid and 2-((E)-2-(3-formyl- 4-hydroxyphenyl)-1-diazenyl)benzoic acid and their tri-n-butyltin(IV) complexes were evaluated by using sea urchin early developmental stages as recommended model organisms for toxicity tests. The novel complexes, as the parent tri-n-butyltin(IV) chloride (TBTCl), caused mitosis block and induced high embryonic mortality in sea urchin. Copyright 2005 John Wiley & Sons, Ltd.
A simple sperm/fertilization bioassay, primarily using sea urchin (and sand dollar) gametes, was improved to yield a quick, sensitive, and cost-effective procedure for measuring toxicity in marine waters. Standard sperm bioassays are conducted by exposing sperm cells to test solutions for 60 min prior to addition of eggs to the test solution for fertilization. Reduced fertilization success (as indicated by the presence or absence of the obvious fertilization membrane) is used as an indicator of toxic effects on sperm viability and/or the fertilization response. This study, in conjunction with earlier work, has shown that the results of sperm bioassays can be affected by a number of factors including temperature, pH, salinity, sperm:egg ratios, sperm exposure times, test materials, and echinoid species. Each of these factors have been considered in designing the standard conditions for the improved test. Examples of the effect of these factors on the test results are illustrated, using silver as a reference toxicant.
The sensitivity to some chemical agents was examined comparatively at sperm, fertilization, cleavage, blastula, gastrula, pluteus and metamorphosis stages of a sand dollar from Japanese waters (Peronella japonica) and a sea urchin from the Pacific coast of Australia (Heliocidaris erythrogramma). These agents included Cu sulphate, ABS and NH3 chloride. Responses observed included departures from control rates of fertilization and developmental reduction at the attainment of first cleavage, gastrula, pluteus or metamorphosis. Developmental anomalies were noted at the fertilization, 2-cell, gastrula, pluteus and metamorphosis stages. Using minimum effective concentrations of the 3 chemicals at various developmental stages of P. japonica, it was found that sensitivity to chemicals varies from fertilization to metamorphosis. It seems that sperm activity is the most sensitive, and that fertilization and gastrulation are more sensitive than first cleavage, blastulation and pluteus formation. H. erythrogramma seems to show nearly the same responses to Cu, but is more sensitive at metamorphosis.
Oxidizing agents of sulfhydryl groups such as iodosobenzoate, alkylating agents such as iodoacetamide, and mercaptide-forming agents such as cadmium chloride, mercuric chloride, p-chloromercuribenzoate, sodium arsenite, and p-carboxyphenylarsine oxide, added in small concentrations to a suspension of sea urchin sperm produced an increase in respiration. When the concentration was increased there was an inhibition. These effects are explained by postulating the presence in the cells of two kinds of sulfhydryl groups: soluble sulfhydryl groups, which regulate cellular respiration, and fixed sulfhydryl groups, present in the protein moiety of enzymes. Small concentrations of sulfhydryl reagents combine only with the first, thus producing an increase in respiration; when the concentration is increased, the fixed sulfhydryl groups are also attacked and inhibition of respiration is the consequence. Other inhibitors of cell respiration, such as cyanide and urethanes, which do not combine with -SH groups, did not stimulate respiration in small concentration.
There is active uptake of radioactive nickel by fertilized eggs and embryos of the sea urchin Lytechinus pictus. The nickel taken into the cells is free and can be released by the addition of exogenous, non-radioactive nickel. The morphological development of embryos raised in sea water containing 10−2 to 10−6M NiCl2 was investigated. Nickel uptake is initiated right after fertilization, but its effect on development does not appear until much later. Embryos grown in 10−2 and 10−3M NiCl2 cleaved at a normal rate and formed blastulae but did not gastrulate. Embryos grown in 10 −4 to 10−6M NiCl2 were able to gastrulate but failed to develop dorsoventral symmetry and formed radialized larvae.
Sea urchin embryos ( Sphaerechinus granularis) offer the opportunity to analyse toxicity towards cell division and stages of early development. Mercuric chloride (HgCl(2)) arrested early development at the level of the first cell cycle. The toxic effect occurred in a very sharp concentration range around 7 microM HgCl(2). At sub-toxic concentrations of HgCl(2), the morphology and kinetics of early development were comparable to control embryos. The time-dependence of toxicity was short; a 5-min exposure to the toxic concentration of 10 microM HgCl(2) was sufficient to provoke developmental dysfunction whereas continuous exposure to 5 microM HgCl(2) allowed development to occur normally. The effects on early development over this range of concentrations were specific to HgCl(2) toxicity since other heavy metal chlorides had no effect at 30 microM. Thus, the sea urchin model may provide new clues to the molecular mechanisms of HgCl(2) toxicity.
Statistical analysis of water quality parameters including trace metal speciation was undertaken with a view to seeing the interrelationship between different variables and also to identify probable source components in order to explain the pollution status of Chennai Ennore coastal environmental system. Factor analysis has been used in the present work. This is essentially a data reduction technique and will suggest how many variates are important to explain the observed variances in the data. The possible variances in the water quality parameters may be due to either sources of anthropogenic origin or natural variances due to the season or due to different biogeochemical processes that are taking place in the system. When this analysis was carried out with our data on water quality parameters in the above coastal environmental system, we found that the prominent factor or the first factor called the eutrophication factor explained 24.51% of the total variance (comprised of variables like DO, pH, SS, ammonia-N, phosphate and silicate). The second factor called the copper contamination factor explained 10.61% (comprised of variables like labile Cu, total Cu and particulate Cu) and the third factor called metal removal factor explained 10.11% (comprised of variables like particulate Zn, particulate Pb and water temperature) of the variances, respectively. Although there are four more factors, they are all having variances less than 10%. From this study, it is seen that eutrophication is the main source component of pollution to the surface waters of this estuary and its adjacent coastal waters compared to dissolved trace metals.
Algae are often used as food in aquatic metal toxicity tests to maintain the well-being of test animals. Such food addition may change metal bioavailability because of the reduction of aqueous metal concentration and the increase in particle-bound metal concentration. While the importance of aqueous exposure pathway is widely recognized, few studies have determined the contribution of the dietary pathway to the overall metal toxicity to aquatic invertebrates. In this study, we determined the toxicity of both algal-bound copper alone and copper solution containing algae to the larvae of marine polychaete Hydroides elegans. Algae that had been pre-exposed to copper at up to 1024 microg l(-1), when fed to the larvae, did not cause significant abnormal larval development. However, when larvae were exposed to algal-copper mixture, percentage of normal larvae could be modeled as a logistic function of aqueous copper concentration, with a 48-h EC(50) (mean +/- S.E.) of 64.9 +/- 4.8 microg Cul(-1). When the toxicity was expressed using total copper concentration, the EC(50) ranged from 58.4 +/- 4.5 microg l(-1) in the control to 121.9 +/- 9.9 microg l(-1) in the 10(6) cells ml(-1) algal treatment. This study highlights the dependency of copper toxicity on the aqueous exposure pathway in this polychaete and the importance of considering algal binding of the metal in larval toxicological tests.
Hydroides elegans (Haswell) an ideal organism to study pollution in seawater
- P V Raja
- PV Raja
Standard guide for conducting acute, chronic and life cycle aquatic toxicity tests with polychaetous annelids
- American Society
- Testing
Responses of poly-chaete Hydroides elegans life stages to copper stress Our sea, our future: State of the marine environment report for Australia
- Zc
- Wong Nc
- P-Y, Qiu J-W Qian
ZC, Wong NC, Qian P-Y, Qiu J-W (2005) Responses of poly-chaete Hydroides elegans life stages to copper stress. Mar Ecol Prog Ser 285:89–96 Zann LP (1995) Our sea, our future: State of the marine environment report for Australia. Great Barrier Marine Park Authority, Queensland, Australia, pp 54–64
A 48-h larval development toxicity test using the marine polychaete Galeolaria caespitosa Lamarck (Fam. Serpulidae) Annelida: Polychaeta Reproduction of marine invertebrates
- Ke
- Jr
KE, Bidwell JR (2001) A 48-h larval development toxicity test using the marine polychaete Galeolaria caespitosa Lamarck (Fam. Serpulidae). Arch Environ Contam Toxicol 40:489–496 Schroeder PC, Hermans CO (1975) Annelida: Polychaeta. In: Giese AC, Pearse JS (eds) Reproduction of marine invertebrates. Vol-ume 3. Annelids and echiurans. Academic, New York, pp 85–92
The sea urchin: Bioassay for the assessment of damage from environmental contaminants Hydroides elegans (Haswell) an ideal organism to study pollution in seawater. XXVI International Ethological Conference
- G M Cipollaro
- G Corsale
- Ragucci A E Esposito
- Giordano
- Gg
G, Cipollaro M, Corsale G, Esposito A, Ragucci E, Giordano GG, et al. (1986) The sea urchin: Bioassay for the assessment of damage from environmental contaminants. In: Cairns J Jr (ed) Community toxicity testing, ASTM STP 920. American Society for Testing and Materials, Philadelphia, PA, pp 66–92 Raja PV (1999) Hydroides elegans (Haswell) an ideal organism to study pollution in seawater. XXVI International Ethological Conference, August 29, 1999, Bangalore. Adv Ethol 34:225
Legislation and ecotoxicity testing (editorial)
- C W Hickey
- CW Hickey
Toxicidad del mercurio, cobre, cadmio y plomo sobre la embriogenesis del erizo de mar (Paracentrotus lividus)
- N Fernandez
The effects of copper on sperm and eggs of Hydroides elegans
- S Gopalakrishnan
- P V Raja
Metal-ion speciation studies in coastal environmental systems of Chennai Ennore and Palar, Mahabalipuram. Doctoral thesis
- Kuppusamy
Chemical versus biological pollution monitoring Pollution and biomonitoring
- J Cairns
Protocol for using the doughboy scallop Chlamys asperrima (Mollusca: Pectinidae) L. to test the sublethal toxicity of single compounds and effluent. National Pulp Mills Research Program
- R Krassoi
- D Everett
- I Anderson
The optimisation and validation of a marine toxicity test using the New Zealand echinoid, Fellaster zelandiae
- M G Nipper
- M L Martin
- E K Williams
- MG Nipper
Effects of copper and aluminium on reproductive behaviour, gametes, fertilization and early development of a sedentary polychaete Hydroides elegans (Haswell 1883). Doctoral thesis
- S Gopalakrishnan
Effects of oil and pesticides on fertilization and early developmental stages of sedentary polychaete, Hydroides elegans (Haswell, 1883). Doctoral thesis
- M Sellappan
Hydroides elegans (Haswell) an ideal organism to study pollution in seawater. XXVI International Ethological Conference
- Pv Raja
Introduction to aquatic toxicology Fundamentals of aquatic toxicology: Effects, environmental fate and risk assessment
- Gm Rand
- Pg Wells
- Ls Mccarty
Our sea, our future: State of the marine environment report for Australia. Great Barrier Marine Park Authority
- L P Zann
- LP Zann
Protocol for using the doughboy scallop Chlamys asperrima (Mollusca: Pectinidae) L. to test the sublethal toxicity of single compounds and effluent
- R Krassoi
- D Everett
Principles of biological assay
- C W Emmens
- CW Emmens
Standard guide for conducting acute, chronic and life cycle aquatic toxicity tests with polychaetous annelids
- American Society for Testing, Materials
Fundamentals of aquatic toxicology: Effects, environmental fate and risk assessment
- G M Rand
- P G Wells
- L S Mccarty
- GM Rand