PCB, PCDD/F and PBDE levels and profiles in crustaceans from the coastal waters of Brittany and Normandy (France)

Occurrence of polychlorinated biphenyls (PCBs) in the sea anemone Bunodosoma zamponii, sediments and seawater from the southwestern Atlantic

Polychlorinated biphenyls (PCBs) are persistent and bioaccumulable organic compounds. The occurrence of PCBs was assessed in two populations of the intertidal sea anemone Bunodosoma zamponii living under different anthropogenic strains. One location was in vicinity to a wastewater plant (Las Delicias, LD), and the other was a preserved location chosen as a reference site (Punta Cantera, PC). Anemone populations were sampled 4 times (spring, summer, autumn and winter) throughout a year, in addition to seawater and sediment from those areas. PCB loadings ranged from 2.89 to 79.41 ng L^-1 in seawater samples and from 0.07 to 6.61 ng g^-1 dry weight in sediment samples. Total PCB levels ranged from 0.22 to 14.94 and 2.79 to 24.69 ng g^-1 wet weight in anemones from PC and LD, respectively. PCBs concentrations in anemones from LD were significantly greater than PC during spring, summer and winter. The congeners 18 and 44 prevailed in seawater samples, 44 and 52 in sediment and 18 and 132+153 in anemones. Redundancy analysis integrated PCB levels from all matrixes and bolstered contrast between sampling sites. Seasonality was also a relevant factor since during winter PCB loading was greater in sediment and anemone samples, coincident with the rainiest season. Disparity between sites could be due to LD's proximity to the wastewater plant, effect of littoral drift direction and/or asymmetries in anemones physiological condition.

Physiological and histopathological alterations in Capoeta baliki and Squalius pursakensis after caused by some environmental pollutants

The present study was aimed to apply physiological and histological biomarkers of pelagic and benthic fish species as biomonitoring of environmental pollutants. Capoeta baliki and Squalius pursakensis were caught from 5 stations in Kirmir Stream (Turkey). After measuring the total length and weight for condition factor analysis, liver, gill, brain, and kidney tissues of fish were taken for histopathological analysis. Dorsal muscles of fish tissues were analyzed for polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs). The mean condition factor of C. baliki and S. pursakensis were 1.14 and 0.97, respectively. It was indicated that the first one was in good condition than the latter one. According to histopathological observations, the alterations in the tissues may be associated with the environmental pollutants' exposure. The total concentration of PAHs of dorsal muscle of C. baliki and S. pursakensis found ranged from 0.915 to 108.421 µg/kg and 0.601 to 675.248 µg/kg, respectively. The highest total concentrations of OCPs were found as 44.16 µg/kg for C. baliki and as 562.12 µg/kg for S. pursakensis. The PCB 28 (10.83 µg/kg), PCB 52 (10.92 µg/kg), PCB 138 (226.24 µg/kg), and the total concentrations of PBDEs were found as 151.74 µg/kg in only S. pursakensis. The result of the concentrations of the investigated pollutants was generally found higher in S. pursakensis which is a higher trophic level than C. baliki. Histopathological alterations were detected as hyperemia in liver, gill, and brain; as hydrophobic degeneration in liver; hyperplasia in gill; and tubular degeneration in kidney tissues of both species. The obtained result of the study shows that the environmental pollutants may affect the physiological and histological status of fish.

Sex and sex-related differences in gamete development progression impinge on biomarker responsiveness in sentinel mussels

In marine pollution monitoring, the biomarkers recorded in sentinel organisms are influenced by natural confounding factors that may jeopardise their interpretation. Among these confounding factors, little is known about the influence of sex along the annual reproductive cycle. The present investigation aims at contributing to understand how sex and sex-related differences in gamete development progression impinge on biomarker baseline values and on biomarker responsiveness to pollution in sentinel mussels. Mussels (Mytilus galloprovincialis) were collected from a relatively clean locality and from a chronically polluted site in the Basque Coast (Bay of Biscay) in January, April, August and November. Sex and gametogenesis stages were determined for each mussel. Tissue concentration of metals and PAHs was analysed. A battery of biomarkers was investigated: cytochrome c oxidase, pyruvate kinase and phosphoenolpyruvate carboxykinase enzyme activities; levels of protein carbonyls, malondialdehyde and 4-hydroxy-2-nonenal; lysosomal enlargement and membrane stability; intracellular neutral lipid accumulation; cell type composition and thinning of the digestive gland epithelium; and survival-in-air. Sex- and reproductive stage-related differences were found in bioaccumulation and in the values and responsiveness of most of the biomarkers. However, the patterns of sex-related differences were not consistent across all biomarkers. The differences in the biomarker responses between females and males also depended on the season, reflecting the progression of the gametogenesis cycle. Thus, selecting mussels of one specific sex does not seem to be a crucial requisite to carry out biomarker-based monitoring; yet, it is highly recommended to identify sex condition and gamete developmental stage of each mussel to test for the potentially confounding effects of sex, reproductive status and sex-related variability along the reproductive cycle.

Microplastic contamination and pollutant levels in mussels and cockles collected along the channel coasts

Nowadays, environmental pollution by microplastics (<5 mm; MP) is a major issue. MP are contaminating marine organisms consumed by humans. This work studied MP contamination in two bivalve species of commercial interest: blue mussel (Mytilus edulis) and common cockle (Cerastoderma edule) sampled on the Channel coastlines (France). In parallel, 13 plastic additives and 27 hydrophobic organic compounds (HOC) were quantified in bivalves flesh using SBSE-TD-GS-MS/MS to explore a possible relationship between their concentrations and MP contamination levels. MP were extracted using a 10% potassium hydroxide digestion method then identified by μ-Raman spectroscopy. The proportion of contaminated bivalves by MP ranged from 34 to 58%. Blue mussels and common cockles exhibited 0.76 ± 0.40 and 2.46 ± 1.16 MP/individual and between 0.15 ± 0.06 and 0.74 ± 0.35 MP/g of tissue wet weight. Some HOC and plastic additives were detected in bivalves. However, no significant Pearson or Spearman correlation was found between MP loads and plastic additives or HOC concentrations in bivalve tissues for the two species.

EStimating Contaminants tRansfers Over Complex food webs (ESCROC): An innovative Bayesian method for estimating POP's biomagnification in aquatic food webs

Pollution greatly impacts ecosystems health and associated ecological functions. Persistent Organic Pollutants (POPs) are among the most studied contaminants due to their persistence, bioaccumulation, and toxicity potential. Biomagnification is often described using the estimation of a Trophic Magnification Factor (TMF). This estimate is based on the relationship between contamination levels of the species and their trophic level. However, while the estimation can be significantly biased in relation to multiple sources of uncertainty (e.g. species physiology, measurement errors, food web complexity), usual TMF estimation methods typically do not allow accounting for these potential biases. More accurate and reliable assessment tool of TMFs and their associated uncertainty are therefore needed in order to appropriately guide chemical pollution management. The present work proposes a relevant and innovative TMF estimation method accounting for its many variability sources. The ESCROC model (EStimating Contaminants tRansfers Over Complex food webs), which is implemented in a Bayesian framework, allows for a more reliable and rigorous assessment of contaminants trophic magnification, in addition to accurate estimations of isotopes trophic enrichment factors and their associated uncertainties in food webs. Similar to classical mixing models used in food web investigations, ECSROC computes diet composition matrices using isotopic composition data while accounting for contamination data, leading to more robust food web descriptions. As a demonstration of the practical application of the model, ESCROC was implemented to revisit the trophic biomagnification of 5 polyfluoroalkyl substances (PFAS) in a complex estuarine food web (the Gironde, SW France). In addition to the TMF estimate and 95% confidence intervals, the model provided biomagnification probabilities associated to the investigated contaminants-for instance, 92% in the case of perfluorooctane sulfonate (PFOS)-that can be interpreted in terms of risk assessment in a precautionary approach, which should prove useful to environmental managers.

Persistent organic pollutants in sediments, intertidal crabs, and the threatened Olrog's gull in a northern Patagonia salt marsh, Argentina

Persistent organic pollutants (POPs) are of great concern for the environment. In this study we (a) determine levels and distribution of OCPs, PCBs, and PBDEs in sediments and two crab species (Neohelice granulata and Cyrtograpsus altimanus), (b) assess bioaccumulation in crabs, and (c) explore the occurrence of POPs in the Near Threatened Olrog's gull (Larus atlanticus) chicks and eggs in one of the most important salt marsh environments in the South West Atlantic. Sediments, crabs, and gull chicks and eggs showed POPs presence at low levels; being α-endosulfan, PCB-153, and BDE-47 the most represented compounds. In sediments, pollutant concentrations were lower than those reported in Canadian guidelines for the protection of the aquatic life. POP bioaccumulation was recorded in crabs, suggesting a risk to upper trophic level predators. Further studies are needed to understand the trophic effects of POPs in San Blas bay, particularly on the threatened Olrog's gull.

Polychlorinated dibenzo-P-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBS) in bivalve mollusk from Galician Rías (N. W., SPAIN)

The concentrations of PCDD/Fs (2,3,7,8-chlorosubstituted) and three dioxin-like PCBs (PCB 77, PCB 126 and PCB169) were analyzed in bivalve mollusk collected in several Galician Rías between 2006 and 2014. Levels of Total PCDD/Fs ranged from 0.03 to 0.62 pg WHO-TEQ g^-1 wet weight. Total dl-PCBs values were higher than Total PCDD/Fs and ranged from 0.01 to 2.11 pg WHO-TEQ g^-1 wet weight. These concentrations were below those considered safe for human consumption. The PCDD/Fs profile was dominated by 2,3,4,7,8-PeCDF and 2,3,7,8-TCDF with a percentage of 24.95 and 23.87 of the Total PCDD/Fs, respectively. In relation to Total dl-PCBs, CB126 was the priority congener with the highest TEF value (0.1). Principal component analysis (PCAs) indicated a clear separation between the northern (Rías de Ferrol and Coruña) and southern Rías (Ría de Pontevedra and Vigo). The northern Rías were the highest contaminated one. Temporal trends showed important reduction rates suggesting that the regulations on dioxin like contaminants have been effective for quality waters in Galician Rías.

Occurrence of selected halogenated flame retardants in Belgian foodstuff

This paper reports on the occurrence of halogenated flame retardants (HFRs), namely PBDEs, HBCDs, TBBPA, brominated phenols (BrPhs), dechlorane plus (DP) and emerging FRs in a variety of Belgian foodstuffs. A total of 183 composite food samples were analyzed by GC-MS and LC-MS/MS techniques for the presence of HFRs. The analyses revealed that 72% of the samples was contaminated with HFRs to some extent. The highest number of contaminated samples was observed within the group 'Potatoes and derived products', 'Fish and fish products' and 'Meat and meat products', while the least contaminated group was 'Food for infants and small children'. The total HFR content ranged from <LOQ to 35.4 ng/g ww with an average content of 1.2 ng/g ww and median of 0.25 ng/g ww. The samples with the highest total HFR levels were canned king crab, fresh mackerel, Emmental cheese, fresh eel and plaice. The most frequently detected HFRs were PBDEs and BrPhs being present in almost all food groups, and among the individual HFRs, the most frequently found compounds were BDE-47 (53%), BDE-209 (46%) and 246-TBP (40%). TBBPA, DPs, TBPH and γ-HBCD occurred with a frequency of less than 5%. TBBPS, 26-DBP, HBB, TBB and BTBPE were not detected in any of the analyzed food samples.

Concentration of polychlorinated biphenyl (PCB) congeners in the muscle of Clarias gariepinus and sediment from inland rivers of southwestern Nigeria and estimated potential human health consequences

The distributions of polychlorinated biphenyl (PCB) congeners were determined in sediment and muscle of the African sharptooth catfish (Clarias gariepinus) from the Ogun and Ona rivers, southwest Nigeria. In addition, the effect of PCB congeners on condition factor (CF) and associated human health risk was assessed using muscle levels for a noncarcinogenic hazard quotient (HQ) calculation. Elevated concentrations of high-molecular-weight (HMW) PCB congeners were detected in sediment and fish downstream of discharge points of both rivers. A significant reduction in fish body weight and CF was observed to correlate with high PCB congener concentrations in the Ona River. A principal component (PC) biplot revealed significant site-related PCB congener distribution patterns for HMW PCB in samples from the Ogun River (71.3%), while the Ona River (42.6%) showed significant PCB congener patterns for low-molecular-weight (LMW) congeners. Biota-sediment accumulation factor (BSAF) was higher downstream for both rivers, presenting PCB congener-specific accumulation patterns in the Ona River. Significant decreases in fish body weight, length and CF were observed downstream compared to upstream in the Ona River. The non-carcinogenic HQ of dioxin-like congener 189 downstream in both rivers exceeded the HQ = 1 threshold for children and adults for both the Ogun and Ona rivers. Overall, our results suggest that industrial discharges contribute significantly to PCB inputs into these rivers, with potential for significant health implications for neighboring communities that utilize these rivers for fishing and other domestic purposes.

Assessment of PCB and chlorinated pesticide accumulation in mussels at Kaštela Bay (Eastern Adriatic)

The biological response of mussels Mytilus galloprovincialis, resident and transplanted to cages, to contamination with anthropogenic pollutants from Kaštela Bay, located in the central part of the eastern Adriatic coast, was investigated. The main purpose of this paper is to trace the accumulation of PCBs and chlorinated pesticides (HCB, lindane, heptachlor, aldrin, p,p'-DDTs) as a direct measure of potential contaminant availability to organisms, in a period from 2000 to 2011. In order to do so, cultured mussels (Mytilus galloprovincialis) of the same size and age were transplanted from the unpolluted Mali Ston Bay to the Kaštela Bay. Sampling was performed bimonthly, and the level of target contaminants in whole soft tissue was determined. After two months of exposure, the concentration of PCBs in transplanted mussels increased on average 6.5-times, and of DDTs 2-times, while the intensity of changes for HCB, lindane, heptachlor and aldrin was negligible. Seasonal variation of pesticide content was similar without a significant change throughout the experimental period, while that of PCBs was somewhat different showing increased accumulation in summer. Seasonal and spatial variation of organochlorines in the Kaštela Bay was likely the result of prevailing environmental rather than biological parameters. In accordance with prevailing hydrodynamic cycling, contaminant concentration decreased in acyclonic direction towards the exit of the Bay. Measurement of target contaminants in resident mussels sampled from the most contaminated area of the Bay exhibited decreasing concentrations of lindane, aldrin and p,p'-DDTs. However, PCBs exhibited statistically significant increasing concentrations in relation to the slightly increasing concentrations of HCB. With regard to human health, organochlorine (OC) levels in the mussel tissue were below prescribed limits for human consumption.

The English Channel: Contamination status of its transitional and coastal waters

The chemical contamination (organic compounds, metals, radionuclides, microplastics, nutrients) of English Channel waters has been reviewed, focussing on the sources, concentrations and impacts. River loads were only reliable for Pb, whereas atmospheric loads appeared robust for Cd, Pb, Hg, PCB-153 and γ-HCH. Temporal trends in atmospheric inputs were decreasing. Contaminant concentrations in biota were relatively constant or decreasing, but not for Cd, Hg and HBCDD, and deleterious impacts on fish and copepods were reported. However, data on ecotoxicological effects were generally sparse for legacy and emerging contaminants. Intercomparison of activity concentrations of artificial radionuclides in sediments and biota on both Channel coasts was hindered by differences in methodological approaches. Riverine phosphate loads decreased with time, while nitrate loads remained uniform. Increased biomass of algae, attributable to terrestrial inputs of nutrients, has affected benthic production and shellfisheries. A strategic approach to the identification of contaminant impacts on marine biota is recommended.

Persistent organic pollutants in a marine bivalve on the Marennes-Oléron Bay and the Gironde Estuary (French Atlantic Coast) - part 1: bioaccumulation

The aim of this study was to determine 1) the relevance of using the Pacific oyster Crassostrea gigas as a sentinel organism, at a juvenile stage, for polycyclic aromatic hydrocarbon (PAH) and persistent organic pollutant (polychlorobiphenyl, PCB, polybromodimethylether, PBDE, and organochlorine pesticide, OCP) contamination, 2) the potential levels of chemical organic contamination in the Marennes-Oléron Bay, and their potential sources and 3) the potential influence of physiological or environmental factors on contaminant body burdens in oysters. To this end, juvenile oysters purchased from an oyster hatchery were transplanted to a reference site, in Bouin, and to different transplantation sites in the Marennes-Oléron Bay, the first oyster production area in France, and in the Gironde Estuary, the biggest estuary in Occidental Europe. Transplantations were done during summer and winter. Whole oyster soft tissues from each site were analysed for PAHs, PCBs, PBDEs and OCPs. Results obtained with a transplantation period of 3months suggest that C. gigas, at the juvenile stage, is a relevant sentinel organism for short-term assessment of contamination for these contaminants. In addition, no significant effects of physiological factors on contaminant body burdens were observed. Principal component analysis revealed two distinct groups of contaminants (PAHs and OPCs, and PCBs and PBDEs) and three groups of sites: 1) the reference site, 2) Les Palles (LP) and Boyard (BOY) in winter and 3) all the other sites. The group of LP and BOY was clearly defined by the levels of PAHs and OCPs, suggesting higher levels of contamination of these chemical compounds on these sites, potentially due to local contamination sources. In addition, no relevant effects of physiological or environmental factors on contaminant body burdens were observed. Results suggest also a predominance of contaminants related to agricultural activities along the Marennes-Oléron Bay, and therefore, further studies on the presence of pesticides in this region should be considered.

Monitoring of PCDD/Fs and dioxin-like PCBs and seasonal variations in mussels from the Mar Grande and the Mar Piccolo of Taranto (Ionian Sea, Southern Italy)

The levels and specific profiles of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in Mytilus galloprovincialis from the Mar Grande and the Mar Piccolo of Taranto were determined during the extensive monitoring plan of Local Health Authority to assess PCDD/Fs and DL-PCBs contamination in food and farm products, within 20 km from the industrial areas of Taranto, between March and December 2011. The average Total Toxicity Equivalence (TEQ) values for the sum of PCDD/F and DL-PCBs ranged from 1.61 to 5.63 pg WHO2005-TEQ g(-1) wet weight basis, with the highest in the first inlet of the Mar Piccolo. In particular, DL-PCBs were the dominant chemicals in all samples, followed by PCDFs and PCDDs. Congener patterns in mussels were similar, indicating a homogeneous behavior in studied areas and, probably, the same type of source. The seasonal concentrations trend showed a relevant increase of dioxin and dioxin-like PCBs TEQs during the summer months, exceeding the limits set by the European Community for food and foodstuff. Reducing PCDD/Fs and PCBs is necessary to decrease contamination levels in order to safeguard marine ecosystem and human health in the Taranto area.

Induction of CYP1A and ABC transporters in European sea bass (Dicentrarchus labrax) upon 2,3,7,8-TCDD waterborne exposure

The aim of this study was to characterize the responsiveness of CYP1A and ABC transport proteins in European Sea bass (Dicentrarchus labrax) waterborne exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) (46 pg/L) for 24 h and 7 days. Genes modulation (abcb1, abcc1-2, cyp1a), EROD activity were investigated in liver and 2,3,7,8-TCDD bioconcentration in liver and muscle. TCDD induced significantly cyp1a gene expression and EROD activity at 24 h and 7 d. A significant up-regulation of abcb1 was also observed but only after 7 days. No modulation of abcc1 and abcc2 genes was observed. Waterborne TCDD exposure was able to induce CYP1A and abcb1 encoding for P-glycoprotein in juvenile of European sea bass.

Analysis of estrogens and estrogen mimics in edible matrices--a review

This review provides a brief survey of the biological effects of selected endocrine-disrupting compounds that are formed after internal exposure of organisms. Further, the present analytical methods available for the determination of these compounds in foodstuffs are critically evaluated. The attention is primarily devoted to the methods for sample pretreatment, which are the main source of errors and are usually the most time-consuming step of the whole analysis. This review is focused on selected natural and synthetic estrogens, estrogen conjugates, and chemical additives used in the plastic industry that can act as estrogen mimics.

Genotoxicity and development effects of brominated flame retardant PBDEs and UV-exposed PBDEs on grass shrimp (Palaemonetes pugio) embryo

To understand how polybrominated diphenyl ethers (PBDEs) affect the hatching sensitivity of grass shrimp embryos in different developmental stages, the hatching rates of embryos were measured after PBDE exposure on the early- and late-stage embryo of grass shrimp. PBDEs had no clear influence on the hatching rate. Also, to investigate on the reproductive and genetic toxicities of UV-exposed PBDEs, the hatching rate and DNA damage of stage 7 embryos were also measured. PBDEs had no significant impact on the hatching rate and DNA damage of grass shrimp in most experimental conditions regardless of embryo developmental stage or UV exposure, but in the case of UV-exposed BDE-47, the hatching rate was decreased, suggesting a potential reproductive toxicity. This research is meaningful because it is the first study to propose that PBDEs can cause reproductive toxicity in marine organism, after flowing into the ocean and undergoing photochemical reactions stimulated by UV.

Polybrominated diphenyl ethers disrupt molting in neonatal Daphnia magna

Polybrominated diphenyl ethers (PBDEs) are flame-retardants which can bioaccumulate and biomagnify and are found worldwide despite their banned usage in some countries. In recent years, the possibility that PBDEs may disrupt endocrine functions in vertebrates has been well investigated, but little attention has been paid to the endocrine disrupting potential in aquatic invertebrates. The current study aimed to investigate whether PBDEs affect molting in neonatal Daphnia magna. Prior to molting studies, 48 h LC50 values were tested for several environmentally prevalent PBDEs: PBDEs-28, -47, -99, -100 and -209. The 48 h LC50s determined were 110.7, 7.9, 2.6, and 11.1 μg/L for PBDEs-28, -47, -99, and -100, respectively, but the highest concentration of PBDEs-209 tested (2.5 mg/L) did not affect survival at 48 h. Sublethal concentrations of these were used to investigate their potential effects on molting, assessed by the time taken to reach 4 molts. Molting studies found that PBDE-28 at 12 μg/L significantly increased the time it took to complete 4 molts. PBDE-47 at 20 μg/L inhibited daphnid molting initially but such an inhibitory effect disappeared with the prolongation of exposure due to the death of sensitive individuals. No other PBDEs affected molting at the concentrations tested, while still maintaining relatively high survival rates. In conclusion, this study found that PBDEs-28 and -47 can delay molting at μg/L concentrations, which raises concern for disrupted molting in crustaceans exposed to PBDEs.

Differences in cytochrome P450 enzyme activities between fish and crustacea: relationship with the bioaccumulation patterns of polychlorobiphenyls (PCBs)

Variations in cytochrome P450 enzyme (CYPs) distribution and function between animal groups could result in differential metabolism and elimination kinetics for certain contaminants. Although a number of studies have suggested that differences in polychlorobiphenyl (PCB) accumulation profiles between crustacea and fish might result from differential CYP patterns, the relationship between PCB bioaccumulation and CYP capacities has not been demonstrated in these organisms. In the present study we investigated the hepatic microsomal catalytic activities in three deep-sea fish species, Alepocephalus rostratus (Alepocephalidae), Coelorinchus mediterraneus (Macrouridae), and Lepidion lepidion (Moridae), and the decapod crustacean Aristeus antennatus (Decapoda), using six fluorescent CYP-mediated substrates, namely ER (7-ethoxyresorufin), PR (7-pentoxyresorufin), BR (7-benzyloxyresorufin), CEC (3-cyano-7-ethoxycoumarin), DBF (dibenzylfluorescein) and BFC (7-benzyloxy-4-trifluoromethylcoumarin). Furthermore, we related the metabolic activities to the accumulation patterns of 41 PCB congeners in the muscle of these organisms. The results indicated a marked difference in the presence and activities of CYP isoforms between fish and the crustacean A. antennatus. Liver microsomes of the three selected fish species were capable of metabolizing all six CYP-mediated substrates and enzymes were identified as primarily belonging to CYP1A and CYP3A subfamilies. In contrast, hepatopancreas microsomes from A. antennatus only showed activity for PR and DBF substrates, generally related to mammalian CYP2-like enzymes. Furthermore, a direct relationship between metabolic activities and PCB accumulation profiles could be established. Results revealed that A. antennatus accumulated significantly higher proportions of PCBs 28, 52, 118, 138, 158 and 169 than fish, which is in accordance with the previously observed lack of CYP1A-like biotransformation capacities. Moreover, A. antennatus exhibited lower levels of PCBs 87, 149, 153, 170, 180, 183, 194 and 206 indicating that this crustacean is able to metabolize congeners considered mammalian CYP2B inducers. Hence, the present findings highlight the role of CYP-mediated metabolism in the congener-specific accumulation of PCBs in aquatic organisms and stress the need to further investigate quantitative and qualitative differences in xenobiotic metabolism among animal groups.

Classic and novel brominated flame retardants (BFRs) in common sole (Solea solea L.) from main nursery zones along the French coasts

Brominated flame retardants (BFRs) were investigated in juvenile common sole from nursery zones situated along the French coast in 2007, 2008 and 2009. Extensive identification was performed with regard to PBDEs, novel BFRs 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) and decabromodiphenylethane (DBDPE), and other non-PBDE BFRs, namely, hexabromobenzene (HBB) and 2,2',4,4',5,5'-hexabromobiphenyl (BB-153). Polybrominated diphenyl ether (PBDE) concentrations (Σ 14 congeners) ranged from 0.01 ng/g to 0.16 ng/g wet weight (ww) in muscle, and 0.07 ng/g to 2.8 ng/g ww in liver. Concentrations were in the lower range of those reported in the literature in other European locations. Lower PBDE concentrations, condition indices and lipid contents were observed in the Seine estuary in 2009, possibly in relation to a lower water flow. The PBDE patterns and ratios we observed suggested that juvenile sole have a relative high metabolic degradation capacity. Non-PBDE BFRs were detected at lower levels than PBDEs, i.e., within the < method detection limit - 0.005 ng/g ww range in muscle, and < method detection limit - 0.2 ng/g ww range in liver. The data obtained is of particular interest for the future monitoring of these compounds in the environment.

Organochlorine pesticides, polychlorinated biphenyls and trace elements in wild European sea bass (Dicentrarchus labrax) off European estuaries

Polychlorinated biphenyls (PCBs) and organochlorine pesticides like dichloro-diphenyl-trichloroethane (DDTs), hexachlorocyclohexanes (HCHs), aldrin, dieldrin and trace elements (Cd, Cu, Se, Pb, Zn and Hg) were analysed in the muscle of European sea bass (Dicentrarchus labrax) sampled in Atlantic coastal regions near several important European river mouths (Gironde, Charente, Loire, Seine and Scheldt). High contamination levels were measured in the muscles of European sea bass sampled in the coastal regions near those river mouths (e.g. Σ ICES PCB=133-10,478 μg kg(-1) lw and Hg=250-2000 μg kg(-1) dw). The Scheldt and the Seine are still among the most contaminated estuaries in Europe. Each region presented their specific contamination patterns reflecting different sources due to the input of the respective rivers. As fish and fishery products are the main contributors of the total dietary intake of organochlorinated pollutants, regular consumption of European sea bass with the reported contamination levels may represent a significant exposure route for the general human population.

PCDD/Fs and dioxin-like PCBs in sediment and biota from the Mondego estuary (Portugal)

The concentrations of 17 polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) were measured in sediment and key species as an initial investigation on PCDD/Fs and dl-PCBs contamination in the Mondego estuary (Portugal). The results demonstrated that the values of the total PCDD/Fs (∑PCDD/Fs) concentrations were considerably lower than those of the sum of dl-PCBs (∑dl-PCBs) in all the studied samples. Regarding the contribution of individual congeners, OCDD was the predominant PCDD/F and the mono-ortho PCB 118 and PCB 105 were the dominant PCBs in the majority of the samples. Our results suggest that PCDD/Fs and PCBs behave quite differently along the aquatic food web: ∑PCDD/Fs concentrations were lower in higher trophic-level organisms with fish presenting a distinct PCDD/Fs congeners profile; on the contrary, the higher ∑dl-PCBs values were found in upper-level biota, although not exclusively, and quite similar dl-PCBs congener profiles were observed in nearly all the studied species.

Accumulation of current-use and organochlorine pesticides in crab embryos from northern California, USA

Invertebrates have long been used as resident sentinels for assessing ecosystem health and productivity. The shore crabs, Hemigrapsus oregonensis and Pachygrapsus crassipes, are abundant in estuaries and beaches throughout northern California, USA and have been used as indicators of habitat conditions in several salt marshes. The overall objectives of the present study were to conduct a lab-based study to test the accumulation of current-use pesticides, validate the analytical method and to analyze field-collected crabs for a suite of 74 current-use and legacy pesticides. A simple laboratory uptake study was designed to determine if embryos could bioconcentrate the herbicide molinate over a 7-d period. At the end of the experiment, embryos were removed from the crabs and analyzed by gas chromatography/mass spectrometry. Although relatively hydrophilic (log K(OW) of 2.9), molinate did accumulate with an estimated bioconcentration factor (log BCF) of approximately 2.5. Following method validation, embryos were collected from two different Northern California salt marshes and analyzed. In field-collected embryos 18 current-use and eight organochlorine pesticides were detected including synthetic pyrethroids and organophosphate insecticides, as well as DDT and its degradates. Lipid-normalized concentrations of the pesticides detected in the field-collected crab embryos ranged from 0.1 to 4 ppm. Pesticide concentrations and profiles in crab embryos were site specific and could be correlated to differences in land-use practices. These preliminary results indicate that embryos are an effective sink for organic contaminants in the environment and have the potential to be good indicators of ecosystem health, especially when contaminant body burden analyses are paired with reproductive impairment assays.

Organic pollutants in microplastics from two beaches of the Portuguese coast

Microplastics pose a threat to coastal environments due to their capacity to adsorb persistent organic pollutants (POPs). These particles (less than 5 mm in size) are potentially dangerous to marine species due to magnification risk over the food chain. Samples were collected from two Portuguese beaches and sorted in four classes to relate the adsorption capacity of pollutants with color and age. Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and DDTs were analysed on pellets through gas chromatography mass spectrometry (GC-MS), and types of plastic were identified using Fourier transformed infra-red spectroscopy (micro-FTIR). Microplastics were mostly polyethylene and polypropylene. Regarding sizes, some fibres ranged from 1 to 5 μm in diameter and were 500 μm in length. The majority of samples collected had sizes above 200 μm. Black pellets, unlike aged pellets, had the highest concentrations of POPs except for PAHs in Fonte da Telha beach. PAHs with higher concentrations were pyrene, phenantrene, chrysene and fluoranthene. Higher concentrations of PCBs were found for congeners 18, 31, 138 and 187. Further investigation is necessary to understand the relationship between plastic degradation and adsorption for different pollutants.

Occurrence of polybrominated diphenyl ethers in fish and shellfish downstream from electronic-waste recycling plants

We measured 39 polybrominated diphenyl ethers (PBDEs) in the muscle tissue of three species of fish (Sciaenops ocellatus, Sparus macrocephalus, and Lateolabraxjaponicus) and four species of shellfish (Tegillarca granosa, Cyclina sinensis, Sinonovacula constricta, and Ostrea cucullata) that were collected downstream of electronic-waste recycling plants in Taizhou, China. A total of 24 PBDE congeners (PBDE24) in the samples were detected. The sigma PBDE24 (total PBDE) ranged from 545.4 to 1688.7 ng/kg ww (wet weight). The mean sigma PBDE24 concentration was 1382.6 ng/kg ww in fish and 858.1 ng/kg ww in shellfish. The lower brominated congeners were detected at relatively high concentrations in all species. The penta-products, produced from e-waste, were found at relatively low levels. A principal component analysis suggested a significant correlation among di-, tri-, tetra-, and hepta-BDEs for the three species of fish. Similarly, we found a significant correlation between mono- and tri-BDEs in the shellfish. Our results suggested that the processes of PBDE metabolism and elimination were similar in both fish and shellfish. In addition, the primary source of PBDEs appeared to be from the debromination of high brominated PBDEs.

Dioxin and PCB contamination in Chinese mitten crabs: human consumption as a control mechanism for an invasive species

The Chinese mitten crab Eriocheir sinensis is an invasive species in North American and northeastern European rivers and estuaries, especially the Thames, England, with the potential to cause considerable ecological and structural environmental damage. The brown meat of sexually ripe mitten crabs is highly prized in far eastern restaurants, suggesting that harvesting for culinary purposes offers a potential population control mechanism. We have analyzed tissues of Thames and Dutch mitten crabs for potentially toxic dietary contaminants, showing that the brown meat contains raised concentrations of dioxins (polychlorinated dioxins and polychlorinated dibenzofurans) and PCBs (polychlorinated biphenyls), organochlorines which are chronic toxins. We have compared estimated daily intakes of these toxins by consumers of meals of mitten crab brown meat against their suggested European Tolerable Daily Intakes (TDI), concluding that a male adult or female beyond childbearing age could consume several portions per week derived from Thames crabs, but fewer from the Dutch crabs. With a caveat that excessive consumption of mitten crab brown meat could lead to exposures of potential concern, particularly in the case of children and women of child-bearing age, it does appear that the harvesting of mitten crabs from the Thames for culinary use need not be discouraged.

How to minimize formation and growth of tumours: potential benefits of decapod crustaceans for cancer research

Tumours have only rarely been observed in the decapod crustaceans, a large animal group of more than 10,000 species that includes the commercially important and well investigated shrimp, lobsters, crayfish and crabs. Analysis of the literature and information from cancer and diseases data bases revealed a total of 15 incidences, some of them being questionable. Even in the long-lived species, which can reach life spans of almost 100 years, neoplasias are virtually unknown. The data published so far suggest that the strikingly different frequencies of carcinogenesis between decapods and other well investigated animal groups like mammals, fish, insects and molluscs is based on differences of the metabolic pathways for carcinogens, the immune systems, and the regulation of stem cells. Therefore, representatives of the Decapoda may serve as useful models to study how organisms can successfully prevent or control spontaneously and environmentally induced cell proliferation. A particularly promising candidate for in-depth investigation of these topics is the marbled crayfish, a rather new clonal lineage that is presently being introduced as a laboratory model in development and epigenetics.

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in marine mussels from French coasts: levels, patterns and temporal trends from 1981 to 2005

The levels and temporal trends of toxic polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in archived marine mussels collected between 1981 and 2005 from selected sites along French coasts. The geographical distribution and levels of PCDD/Fs generally reflect regional inputs of these contaminants: the highest concentrations were determined in samples from the Seine river estuary (English Channel) and Toulon area (Mediterranean coast); the lowest levels were determined in Corsica (Mediterranean Sea). PCDD/F isomeric composition showed a fairly homogeneous distribution pattern throughout the various sampling sites. This pattern, dominated by 2,3,7,8-TCDF and OCDD, can be considered as typical for the study species. However, on a more local scale, some differences in isomeric composition in mussels were identified in relation to local source characteristics. The time trend study showed a pronounced decrease in PCDD/F concentrations over the 24-year period at most sites, except Toulon on the Mediterranean Sea, where the decrease was not significant. This overall decrease probably reflects the general drop in PCDD/F emissions in Europe since 1980. However, high concentrations were determined in mussels collected in recent years (1999, 2001 and 2005) from the mouth of the Seine river. These concentrations are related to particular hydrological conditions, and intensive sediment dredging due to a new port construction at the mouth of the estuary. The results presented in this paper provide reference data on the contamination of shellfish by persistent organic pollutants in the marine environment.

Profiles of Polybrominated Diphenyl Ethers in Aquatic Biota

The profiles (concentrations scaled to a sum of 100) of polybrominated diphenyl ethers (PBDEs) in aquatic fauna differ from those of the commercial PBDE formulations, particularly by a much higher proportion of the congener 47. At the same time, the profiles reported by different authors vary a great deal and no patterns related to species, localities, etc. are obvious. It seems that there are systematic differences among the reporting laboratories, and measurement errors within the same laboratory may also play a role. However, the profiles of PBDEs in fish from the Baltic are very similar and form a tight "cluster". PBDE profiles in crustaceans appear different from those in fish.

Levels and trends of HBCD and BDEs in the European and Asian environments, with some information for other BFRs

In this paper, we review recent data for brominated flame retardants (particularly BDEs, HBCD and TBBP-A) in samples from the European and Asian environments, including recent temporal trend studies. Research is active and we cite over 100 studies published during 2005-2007. Environmental compartments studied comprise the atmosphere, indoor and outdoor air, sewage sludges, soils and sediments and a variety of biological samples and food chains. Findings include that the lack of reference materials for use in analytical quality control and method validation identified earlier has been addressed, and certified concentrations are now available for a number of BDE congeners in six pre-existing and one new reference materials. BDE209 was certified in three samples of indoor dust. The analysis of BDE209 remains problematic, but suitable methods for its determination are available and need to be applied. The contamination of indoor environments with BFRs has been recognised as representing a significant uptake pathway, particularly via dust. Additional data for TBBP-A are needed from areas, where it is produced and used, primarily Asia, as the worst-case scenario. As a reactive flame retardant it is less likely to leach from finished products. Also, issues regarding the importance of e-waste recycling as a source of BFRs to the local populations and the local environment require urgent study, certainly in China and possibly elsewhere. Generally, trends show a levelling in concentrations of BDEs and increases in concentrations of HBCD wherever determined and BDE209 in Asia.

Toxicity and physiological effects of brominated flame retardant PBDE-47 on two life stages of grass shrimp, Palaemonetes pugio

This study examined the effects of a polybrominated diphenyl ether (PBDE) compound, PBDE-47, on adult and larval stages of the estuarine grass shrimp (Palaemonetes pugio). The 96-h LC50 test resulted in an estimate of 23.60 microg/L (95% confidence interval=14.51-38.37 microg/L) for larval shrimp. Adult shrimp had a higher 96-h LC50 of 78.07 microg/L (95% CI=65.1-93.63 microg/L). Four physiological biomarkers glutathione (GSH), lipid peroxidation (LPx), cholesterol (CHL) and acetylcholinesterase (AChE) were then assessed to study the sublethal effects of PBDE-47 exposure. GSH, LPx and AChE levels in both adults and larvae were not affected by PBDE-47 at concentrations up to 50 microg/L for 96 h. CHL levels were elevated in adults and larvae at the lowest exposure concentrations tested, but significant differences were found only in adult exposures. Effects associated with PBDE-47 aqueous exposures were observed at levels well above those reported in the environment.

Flame retardants (PBDEs) in marine turtles, dugongs and seafood from Queensland, Australia

Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in numerous products. These compounds have been found to enter the marine environment where they have the potential to bioaccumulate in biota. Limited information is currently available concerning the levels of PBDEs in Australian marine wildlife. This study presents baseline information on PBDE levels in a variety of marine species from Queensland, Australia and considers the influence of species-specific factors on contaminant levels and tissue distribution in marine turtles. Overall, the PBDE levels measured in this study are relatively low compared to marine biota from the northern hemisphere, indicating low level input into the marine system of Queensland. This is in general agreement with global estimates which suggest low PBDE usage in Australia. Previous studies, however, have found relatively high PBDE levels in Australian human milk and sera. This discrepancy in contamination trends between terrestrial and marine biota suggests that future transport of PBDEs may occur to the marine system in Australia.

Congener-specific accumulation and trophic transfer of polychlorinated biphenyls in spider crab food webs revealed by stable isotope analysis

Polychlorobiphenyls (PCB) and stable isotopes (delta15N and delta13C) were analyzed in the spider crab (Maja brachydactyla) food web from the Iroise Sea (Western Brittany) and the Seine Bay (Eastern English Channel). PCB concentrations were all significantly higher in organisms from the Seine Bay than those from the Iroise Sea. PCB patterns were strongly related to the feeding mode of the species, and increased influence of higher chlorinated congeners was highlighted with trophic position of the organisms. PCB concentrations (lipid normalized) were significantly related to the isotopically derived trophic level (TL) in spider crab food webs. The highest trophic magnification factors (TMFs) were calculated for the congeners with 2,4,5-substitution, and were lower in the Seine Bay compared to the Iroise Sea. The confrontation of PCB and TL data also revealed biotransformation capacity of decapod crustaceans for specific congeners based on structure-activity relations.