Biomagnification of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) studied in pike (Esox lucius), perch (Perca fluviatilis) and roach (Rutilus rutilus) from the Baltic Sea

Seasonal variations in the atmospheric concentrations of polybrominated diphenyl ethers in Kuwait

The study reports fortnightly atmospheric concentrations of PBDEs concomitantly measured at an urban and a remote location over a twelve-month period in Kuwait to examine seasonal variability and urban-rural concentration gradients. The annual mean (and range) of ∑PBDE concentrations was 32 (3-208) pgm(-3) at the remote site and 57 (0.3-445) pgm(-3) at the urban site. Although not statistically significant, the median (29 pg m(-3)) and mean (57 pg m(-3)) concentrations at the urban location were higher than those measured at the remote location (18 and 29 pg m(-3) respectively), consistent with the view that urban centers are an important net source of these compounds to the environment. Although Clausius-Clapeyron plots showed statistically significant correlations (p<0.05) with temperature for low molecular weight congeners (BDEs 28, 47, 100), correlations with the ΣPBDE concentrations were not significant at both urban and remote sites. The seasonal variations in ΣPBDE concentrations were not markedly different at the urban location, but the median summer ΣPBDE concentration at the remote location was significantly higher than winter median ΣPBDE concentrations. The absence in seasonality at the urban location may be due to ongoing primary emissions in urban areas.

Application of compound-specific stable carbon isotope analysis for the biotransformation and trophic dynamics of PBDEs in a feeding study with fish

The debromination and trophic dynamics of PBDEs in fish and whether or not compound-specific isotopic analysis (CSIA) can be used to trace these processes were investigated. Two predator/prey relationships were established in laboratory by two predatory fish species, oscar fish (OF) and redtail catfish (RF) feeding on tiger barb (TB) exposed to a commercial PBDE mixture. Metabolic debromination of PBDEs was observed in the TB and the OF, but not in the RF. The calculated biomagnification factors (BMFs) were uniform for most of the congeners in RF/TB but varied in OF/TB, which can be attributed to the metabolic debromination in the OF. The δ(13)C values of BDE47 and BDE28 were lower in fish than in those in the commercial mixture but the δ(13)C values of BDE99 were slightly higher. These results indicated that CSIA can be used to trace the biotransformation of PBDEs in biota.

Effects of decabromodiphenyl ether (BDE-209) on inter-specific competition between two species of marine bloom-forming microalgae

Decabromodiphenyl ether (BDE-209), a new kind of persistent organic pollutants, was selected to investigate its influence on population growth and inter-specific competition between two species of marine bloom-forming microalgae, Heterosigma akashiwo and Karenia mikimotoi. (1)BDE-209 showed acute toxic effects on both microalgae and H. akashiwo was more sensitive from view of 96 h-EC₅₀ and the ultrastructure variation. (2)The microalgal population growth patterns in mono-culture were density-dependent and the growth of both species in the normal co-culture was significantly depressed by competition (P<0.05) with different initial biomass ratios. BDE-209 exposure significantly changed the growth. (3) Lotka-Volterra competition model was used to simulate the interaction between the microalgae. BDE-209 exposure broke the competitive balance to make competition gradually shift in favor of H. akashiwo. Results suggested BDE-209 did have toxic effects on either microalgal growth or the inter-specific competition, which was quite different from previous reports. Further exploration of the mechanism is needed.

Bioaccumulation of polybrominated diphenyl ethers and several alternative halogenated flame retardants in a small herbivorous food chain

Little is known about the bioaccumulation behavior of polybrominated diphenyl ethers (PBDEs) and other halogenated flame retardants (HFRs) in plants and in herbivores. In the present study, PBDEs and several alternative HFRs (AHFRs) were examined in a small herbivorous food chain (paddy soils-rice plant-apple snails) from an electronic waste recycling site in South China. Mean concentrations of total PBDEs were 40.5, 1.81, and 5.54 ng/g dry weight in the soils, rice plant, and apple snails, respectively. Levels of total AHFRs in the samples were comparable to or even higher than those of PBDEs. The calculated plant to soil concentration ratios for most AHFRs (0.05-3.40) were higher than those for PBDEs (0.02-0.23), indicating the greater bioavailability of the AHFRs in the rice plant. All PBDE congeners and Dechlorane Plus (DP) isomers were biomagnified from the rice plant to apple snails, with mean biomagnification factors (BMFs) of 1.1-5.0.

Polychlorinated dibenzodioxins, dibenzofurans, and biphenyls in fresh water fish from Campania Region, southern Italy

Twenty-eight fish muscle specimens from the main water bodies of the Campania Region were analyzed in our laboratory. On average, results showed a low contamination by PCDDs+PCDFs and a relatively more important presence of DL-PCBs. All specimens were compliant with EU regulatory maximum levels. Cumulative PCDD+PCDF+DL-PCB concentrations (TEQ(TOT)) were comprised in the range 0.223-11.4 pgWHO(97)-TEQ g(-1) fresh weight (fw). DL-PCB contribution to TEQ(TOT) was on average greater than 86% (range, 50.2-97.1%). The cumulative concentrations of 30 non-dioxin-like PCB congeners (Σ(30)(NDL-PCBs)) and of the six indicators (Σ(6)(NDL-PCBs)) were respectively in the ranges 3.30-515 and 1.30-195 ng g(-1) fw. The hybrid clustering approach adopted to analyze the sample-specific congener profiles indentified the main analytical patterns present in the database and, in particular, two main diverse exposure macro-areas that seem to exist north and south of the city of Naples. The distribution of PCDD and PCDF congeners among different species showed significant variations from chub (Leuciscus cephalus), characterized by a higher proportion of low-chlorinated congeners (e.g. 2,3,7,8-T(4)CDD), to eel (Anguilla anguilla), whose contamination consisted mainly of highly chlorinated congeners (e.g. O(8)CDD). To have a more complete perspective in relation to the contaminants present in the environment, the study suggestion is to use benthic as well as pelagic species to obtain an integrated characterization of fish tissue contamination.

Extraction, isolation, and purification of analytes from samples of marine origin--a multivariate task

The development of a multivariate study for a quantitative analysis of six different polybrominated diphenyl ethers (PBDEs) in tissue of Atlantic Salmo salar L. is reported. An extraction, isolation, and purification process based on an accelerated solvent extraction system was designed, investigated, and optimized by means of statistical experimental design and multivariate data analysis and regression. An accompanying gas chromatography-mass spectrometry analytical method was developed for the identification and quantification of the analytes, BDE 28, BDE 47, BDE 99, BDE 100, BDE 153, and BDE 154. These PBDEs have been used in commercial blends that were used as flame-retardants for a variety of materials, including electronic devices, synthetic polymers and textiles. The present study revealed that an extracting solvent mixture composed of hexane and CH₂Cl₂ (10:90) provided excellent recoveries of all of the six PBDEs studied herein. A somewhat lower polarity in the extracting solvent, hexane and CH₂Cl₂ (40:60) decreased the analyte %-recoveries, which still remain acceptable and satisfactory. The study demonstrates the necessity to perform an intimately investigation of the extraction and purification process in order to achieve quantitative isolation of the analytes from the specific matrix.

Biomonitoring of polychlorinated biphenyls (PCBs) in heavily polluted aquatic environment in different fish species

The distribution and concentrations of polychlorinated biphenyls (PCBs) were determined in fish species (European perch Perca fluviatilis, northern pike Esox lucius, pike perch Sander lucioperca, wels catfish Silirus glanus, common carp Cyprinus carpio, European eel Anguilla anguilla, freshwater bream Abramis brama, goldfish Carassius auratus, and roach Rutilus rutilus) in a heavily polluted water reservoir Zemplínska šírava (Slovakia). The study performed at two different time points 5 years apart (2004 and 2009) revealed serious PCB contamination of fish muscle tissue and significant interspecies as well as tissue-specific differences in PCB uptake by fish. Total PCBs broadly correlated with the trophic position of individual fish species within a food chain (P < 0.01). The concentrations were particularly high in predatory fish species, perch, pike, and pike perch (108.0, 90.1, and 113.0 mg kg(-1) lipid wt, respectively), but comparable PCB values were also found in non-predatory detrivorous freshwater bream (128.0 mg kg(-1) lipid wt). The lowest PCB values were surprisingly assessed in European eel (17.1 mg kg(-1) lipid wt). Tissue analysis showed the highest storage capacity of the liver (hepatopancreas in cyprinids) with maximum concentrations recorded found in northern pike (214.0 mg kg(-1) lipid wt) and freshwater bream (163.0 mg kg(-1) lipid wt). Negative correlations, mostly not significant, between the total PCB concentrations and fish weight were observed (P > 0.05). The study has shown that the kind of fish, its feeding habit, and specific conditions of the habitat are mutually interrelated factors that are responsible for significant variations in fish body burdens. A tendency to PCB biomagnification was also proved in some fish species of this water reservoir.

Toxic effects of two brominated flame retardants BDE-47 and BDE-183 on the survival and protein expression of the tubificid Monopylephorus limosus

The toxic effects of two brominated diphenyl ethers (BDE), BDE-47, and BDE-183, on a benthic oligochaete tubificid, Monopylephorus limosus were studied under laboratory conditions. Investigated responses included survival, growth, and protein expression profiles, at BDE concentrations of 1, 10, 100, and 700 ng/g on a dry soil weight basis, with isooctane as the carrier solvent. Body weight losses among treatments were insignificant after 8 weeks of exposure. The 8-wk LC(50) of BDE-47 and -183 were 2311 and 169 ng/g, respectively. By applying multivariate analysis techniques, protein expression patterns were compared and correlated with stressful sources of long-term culture, carrier solvent, BDE-47 and -183. The treatment of 8-wk 100 ng/g BDE-47 was most closely clustered to the 10 ng/g BDE-183 treatment, based on the 40 examined protein spots. This indicated that BDE-183 was more potent to M. limosus, than was BDE-47. The 2-wk and 8-wk controls clustered into different groups indicating the occurrence of physiological changes due to long-term laboratory culture. Additionally, solvent effect was shown by grouping the isooctane carrier to different clusters. With further characterization by principle component analysis, it was found that the separation was mainly contributed by the 2nd principal-component. And, the primarily inhibitory variation was at spots 2 (UMP-CMP kinase) and 40 (plasma retinol-binding protein precursor) in the 8-wk groups. On the contrary, protein spots 16 (cell division control protein 2 homolog) and 24 (mitochondrial DNA mismatch repair protein) showed stimulatory variation. In all, the observed proteomic responses suggest that BDEs disrupted metabolic function in M. limosus and multivariate analysis tool offers significant potential for the assessment of various stress sources at biochemical level.

Seasonal fluctuations of DDTs and PCBs in zooplankton and fish of Lake Maggiore (Northern Italy)

Concentrations of DDTs and PCBs were determined in the zooplankton and in three different fish species (shad, whitefish and roach) collected seasonally during 2009 and 2010 in three sites in Lake Maggiore, a south-alpine lake that has been contaminated by DDT since 1996. As previously observed in 2008, even during 2009 DDTs concentrations were higher in zooplankton than in fish, probably due to the very unstable situation of the lake still influenced by local inputs. The situation changed in 2010, when all DDT compounds increased in fish to levels much higher than those measured in zooplankton. Biomagnification was statistically demonstrated for pp'DDE in all the three fish species, indicating a probable signal of recovery of the lake. Although with respect to total PCBs we observed that the contamination levels varied across time periods and across fish species, biomagnification was evident from zooplankton to fish both in 2009 and in 2010. As concern individual PCBs, biomagnification from zooplankton to all three fish species was significant for PCB 153 and PCB 138.

Occurrence of polybrominated diphenyl ethers, polychlorinated biphenyls, and phthalates in freshwater fish from the Orge river (Ile-de France)

Polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and phthalates were investigated from July 2009 to April 2010 in three fish species from the Orge river, which flows in a densely populated area of Ile-de-France. In two Cyprinidae (roach and chub) and one Percidae (perch), muscle contents in increasing order ranged as follows: 12-18 ng g(-1) dw for PBDEs (Σtri-hepta), 120-170 ng g(-1) dw for PCBs (Σ7), and 2,250-5,125 ng g(-1) dw for phthalates (Σ7). No variation was observed between contaminant contents and lipid levels. No biomagnification was found according to the trophic level for PBDEs and PCBs, whereas for phthalates the highest contents were found in perch. Seasonal variations were observed with the lowest PBDE and PCB contents occurring in July after spawning in roach and perch (p < 0.001). PBDE content followed a decreasing trend-gonad > liver > muscle-whatever the period. For PCBs, gonad and liver contents remained greater than that of muscle (p < 0.05). Our results indicate a preferential accumulation of halogenated compounds in gonad and liver outside the reproduction period. Bioaccumulation factors for PCBs in muscle were significantly correlated to their chlorination degree in perch (p < 0.01) and roach (p < 0.01). In roach, that correlation slope was by decreasing importance order as follows: gonad > liver > muscle. The biota-sediment accumulation factors varied from 0.1 to 29.2, from 1.6 to 4.8, and from 1 to 123.5 for PBDEs, PCBs, and phthalates, respectively. These results contribute to document the use of freshwater fish as bioindicators of river quality.

Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean

Consumption of marine organisms represents one of the main exposure sources of contaminants for human populations. To obtain a global view of the contamination in commercial fish in the NW Mediterranean Sea, we analysed four types of priority contaminants (PCBs, PBDEs, Hg and (137)Cs) in the European hake, Merluccius merluccius, from the Gulf of Lions in relation with organism's trophic level (δ(15)N). All contaminants presented a significant increase in concentration in hake muscle with trophic level. However, obvious differences between contaminants were evidenced. Biomagnification factors (BMF and FWMF) along the hake food web were higher for Hg and CB-153 than for BDE-47 and (137)Cs, and increase in contaminant concentration with trophic level occurred at different rates depending on contaminants. Such differences of biomagnification patterns can be related to physico-chemical properties of the different contaminants.

Polybrominated diphenyl ethers and polychlorinated biphenyls in freshwater fish from Taihu Lake, China: their levels and the factors that influence biomagnification

Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs), two types of persistent organic pollutants that have been used widely, can be released into the environment and accumulate in organisms. To obtain a better understanding of the biomagnification of PBDEs and PCBs in fish, as well as the influences on biomagnification by fish size and physical properties of PBDEs and PCBs, a total of 200 samples of 24 fish species were collected and analyzed from Taihu Lake, the second largest freshwater lake in China. The concentrations of PBDEs and PCBs ranged from 8.59 to 74.28 ng/g lipid weight (lw) and from 10.30 to 165.20 ng/g lw, respectively. Trophic magnification factors (TMFs) were used to estimate the PBDE and PCB biomagnification potentials. The TMF values of PBDEs and PCBs ranged from 0.78 to 2.95 and from 0.92 to 2.60, respectively. Most of the TMFs were greater than 1, indicating that these contaminants were biomagnified in food chains. Fish size might influence the biomagnification evaluation, because different sized fish had different lipid content, leading to different lipid-based concentrations of PBDEs and PCBs. Parabolic relationships were observed between the TMFs and logK(OW) , as well as between the TMFs and the molecular volumes of PBDE and PCB congeners. The congeners with logK(OW) values of approximately 7 or molecular volumes of approximately 8 × 10⁻⁵  nm³ had the greatest biomagnification potentials. Compared to molecular weight, molecular volume seems to be the better standard for analyzing the influence of molecular size on biomagnification.

Changes in patterns of persistent halogenated compounds through a pelagic food web in the Baltic Sea

The concentrations and patterns of persistent halogenated compounds (PHCs), including polychlorinated biphenyls (PCBs), DDT, hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB) and polybrominated diphenyl ethers (PBDEs) were examined in a pelagic food web from the southern Baltic Sea consisting of sediment, zooplankton, sprat, Atlantic salmon and anadromous brown trout. Lipid-normalized concentrations generally increased from low trophic levels to high trophic levels, with the exception of HCHs. Due to high concentrations of PBDEs in some zooplankton samples, biomagnification of BDE-47 was only observed for salmon/sprat and trout/sprat. Sprat collected individually and from salmon stomach had significantly different lipid-normalized concentrations and varied in their PHC pattern as well, possibly indicating a large natural variation within the Baltic Sea. The highest lipid-normalized concentrations were found in brown trout. Salmon and brown trout were similar in their PHC pattern suggesting similar food sources. Variation in PHC patterns among trophic levels was not smaller than that among geographically distinct locations, confirming the importance of comparable trophic levels for the assessment of PHC patterns, e.g. for tracing migratory fish.

Bioaccumulation of persistent organic pollutants (POPs) in fish species from Lake Koka, Ethiopia: The influence of lipid content and trophic position

The concentrations and bioaccumulation of persistent organic pollutants (POPs) were determined in four fish species from Lake Koka, Ethiopia, representing 2-3 levels in the food chain of the lake. Dichlorodiphenyltrichloroethanes (DDTs), endosulfans, polychlorinated biphenyls (PCBs) and chlorpyrifos were identified, with DDTs as the most predominant pesticide, with concentration ranging from 0.05 to 72.53ngg(-1) wet weight (ww). All fish tissue samples collected from different species of the lake contained residues of DDTs. The maximum level of DDTs was found in the fattiest, African sharptooth catfish (Clarias gariepinus) sampled from the lake, with a mean concentration of 15.15ngg(-1)ww. The significant (P<0.05) relationship between concentrations of DDTs and δ(15)N indicates that DDTs biomagnified in the food web of the lake. The 4,4'-DDE to 4,4'-DDT ratio in Oreochromis niloticus (0.6) and Cyprinus carpio (0.5) were below 1, indicating ongoing use of DDTs in the study area and recent exposure of these fish species.

Decabromodiphenyl ether (BDE-209) enters the food web of the River Po and is metabolically debrominated in resident cyprinid fishes

Decabromodiphenyl ether (BDE-209), the primary constituent of a widely used flame retardant formulation, is present at relatively high levels in sediments and macroinvertebrates of the River Po. Since it was demonstrated that BDE-209 can be biotransformed to smaller and more toxic polybrominated dipheyl ethers (PBDEs), the main objective of this study was to assess whether the large quantities of BDE-209 present in the River Po are bioavailable to the higher levels of the food web and are biotransformed in feral fishes. To this aim, 23 cyprinids, mainly common carp, were analysed for the hepatic contents of PBDEs. Contrary to sediments and invertebrates of the same area, no fish sample contained detectable levels of BDE-209. All fishes contained typical PBDE representatives, e.g. BDE-47, BDE-99, BDE-100, BDE-153 and BDE-154, but more importantly they contained three congeners, i.e. BDE-179, BDE-188 and BDE-202, which are not present in any technical formulations and are known products of BDE-209 debromination in fish. The age of carps had no effects on the bioaccumulation of PBDEs. Conversely, the contents of PCBs, which also were determined in the same fish samples, showed a positive correlation with age. Both groups of chemicals displayed a tendency to a higher contamination in male fish. This study shows that BDE-209 enters the food web of the River Po contributing to the load of lower brominated PBDEs and thus to the load of chemical stressors threatening the aquatic life of the major Italian watercourse.

Is PCBs concentration variability between and within freshwater fish species explained by their contamination pathways?

Many chemical, physiological, and trophic factors are known to affect bioaccumulation of polychlorinated biphenyls (PCBs) in biota. Understanding the primary factors affecting fish contamination is critical for predicting and assessing risks to upper-trophic level consumers, including humans. Here we identify PCB contamination pathways that could explain within- and between-species variability in fish concentration levels. Three freshwater river fish species (barbel, chub and bream) were sampled at three sites along the Rhone River (France) where fish consumption is partially prohibited because of PCB levels exceeding the European health-based benchmark. The trophic position was assessed using an innovative approach based on stable isotope analyses and Bayesian inference, which takes into account both isotope data variability and parameter uncertainty. The effect of foraging habitat on fish contamination was addressed using stable isotope mixing models. The fish trophic position and PCB concentrations were found to be unrelated while the exploitation of sediment detrital carbon as a food source appeared to be a critical factor affecting fish contamination. Fish length, PCB concentration of the sediment, and individual fish foraging habitat (exploitation of detrital versus planktonic carbon sources) explained 80% of within- and between-species variability observed in PCB concentrations. These results, obtained for species that have overlapping TPs and exploit different carbon sources, reveal that the important factor in fish PCB contamination is not only what fish consume, but also and essentially the feeding location.

Dietary uptake of polybrominated diphenyl ethers (PBDEs), occurrence and profiles, in aquacultured turbots (Psetta maxima) from Galicia, Spain

Polybromodiphenyl ethers (PBDEs) are one of the many toxic chemicals present in the environment and in the food we eat every day, being fish one of the main sources of persistent organic pollutants in our diet; like other lipid-related contaminants, they are of concern since they can bioaccumulate and biomagnify through the trophic chain. We published a study focused on the dietary uptake of dioxins and furans (PCDD/Fs) and dioxin-like polychlorobiphenyls (dl-PCBs) in a set of samples of Spanish farmed turbot (Blanco et al., 2007). In the present paper, we extend the study to PBDEs to provide more information about the uptake and transfer from feed to fish of halogenated contaminants. PBDEs in the feeds (2.35-4.76 ng g(-1)) were reflected in turbot fillets (0.54-2.05 ng g(-1)): predominant congeners were tetra-BDE 47, penta-BDEs 99 and 100. It is remarkable that tetra-BDE 49, accounting for only 2% in the feed, contributed to 15% of total PBDEs in turbot fillets. Dietary net accumulation values, 30-45%, showed that tri-, tetra-, penta- and hexa-BDEs were as efficiently transferred into turbot as dl-PCBs and tetra- and penta-chlorinated PCDD/Fs. Lipid-normalized biomagnification factors relating concentration in fish and in feed, BMFs>1 were obtained, except for BDE 209. BDE 49 accumulation, 90%, was possibly contributed by metabolism of higher brominated BDEs. Implication in aquaculture management is a need for uncontaminated fish feed to offer safe products.

Complete debromination of tetra- and penta-brominated diphenyl ethers by a coculture consisting of dehalococcoides and desulfovibrio species

Polybrominated diphenyl ethers (PBDEs) are widespread global contaminants due to their extensive usage as flame retardants. Among the 209 PBDE congeners, tetra-brominated diphenyl ether (tetra-BDE) (congener 47) and penta-BDEs (congeners 99 and 100) are the most abundant, toxic, and bioaccumulative congeners in the environment. However, little is known about microorganisms that carry out debromination of these congeners under anaerobic conditions. In this study, we describe a coculture GY2 consisting of Dehalococcoides and Desulfovibrio spp., which is capable of debrominating ∼1180 nM of congeners 47, 99, and 100 (88-100% removal) to the nonbrominated diphenyl ether at an average rate of 36.9, 19.8, and 21.9 nM day(-1), respectively. Ortho bromines are preferentially removed during the debromination process. The growth of Dehalococcoides links tightly with PBDE debromination, with an estimated growth yield of 1.99 × 10(14) cells per mole of bromide released, while the growth of Desulfovibrio could be independent of PBDEs. The growth-coupled debromination suggests that Dehalococcoides cells in the coculture GY2 are able to respire on PBDEs. Given the ubiquity and recalcitrance of the tetra- and penta-BDEs, complete debromination of these congeners to less toxic end products (e.g. diphenyl ether) is important for the restoration of PBDE-contaminated environments.

Polybrominated diphenyl ethers in three commercially important fish from the northwestern Arabian Gulf: occurrence, concentration, and profiles

Polybrominated diphenyl ethers (PBDEs) were measured in three species of fish (yellowfin seabream [Acanthopagrus latus, a predatory fish]; Klunzinger's mullet [Liza klunzingeri, a pelagic fish]; and large-scaled tonguesole [Cynoglossus arel, a demersal fish]) collected from two sites in the northwestern part of the Arabian Gulf, a marginal sea of the tropical Indo-Pacific Ocean. Concentrations of ΣPBDEs ranged from 11 to 57 ng g(-1) lipid weight (lw) for mullet, 5.0-38 ng g(-1) lw for tonguesole, and 2.8-48 ng g(-1) lw for seabream in Kuwait Bay, whereas in the open gulf, concentrations ranged from 6.0 to 160 lw for mullet, 8.3-190 lw for tonguesole, and 7.1-62 for lw for seabream. The congener composition in all species from both sites was dominated by BDEs 47, 99, and 100, which together constituted approximately 90% of the congeners detected. Although no statistically significant intersite differences were found, ΣPBDEs concentrations in mullet were significantly higher than those in seabream (p = 0.01). However, no significant differences existed between mullet and tonguesole (p = 0.28) or between tonguesole and seabream (p = 0.06). ΣPBDE concentrations were negatively correlated with fish mass for all species; however, the correlations were statistically insignificant, suggesting a growth dilution effect.

Halogenated persistent organic pollutants in deep water fish from waters to the west of Scotland

Halogenated persistent organic pollutants [polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs)] along with total lipid, were measured in the liver and muscle of three species of deep water fish (black scabbard, black dogfish (liver only) and roundnose grenadier) collected from the Rockall fishing area, to the west of Scotland, between 2006 and 2008. Both contaminant groups were detected in the muscle and liver, with concentrations of PCBs being higher than PBDEs. There were no significant differences in the PCB or PBDE concentrations between the three species, or different sampling locations in the Rockall fishing area. PCB concentrations (ΣICES (International Council for the Exploration of the Sea)7 PCBs) greater than 500 μg kg(-1) lipid weight were found in 26 of the 106 liver samples. PCB concentrations were compared to OSPAR assessment criteria, concentrations were above background but below Environmental Assessment Criteria. Estimated Toxic Equivalent (TEQ) concentrations, calculated using published models, in the fish muscle and liver indicated that consumption of deep water fish is unlikely to represent a risk to human health. The high squalene content in some of the black dogfish liver necessitated an additional clean-up step, involving gel permeation chromatography, when analyzing for PBDEs. Concentrations of PBDEs were low with many congeners being below detection limits, particularly in the muscle. There are currently no assessment criteria available for PBDEs. Furthermore, there is only very limited data on PBDEs in deep water fish. However, the concentrations observed in this study were similar to the concentrations recently reported in Mediterranean deep water fish.

Distribution, source and risk assessment of polychlorinated biphenyls (PCBs) in urban soils of Beijing, China

The concentration of PCBs in urban soils of Beijing across six land types including business districts (BD), cultural and educational areas (CE), classical gardens (CG), public green (PG), residential areas (RA), and roadsides (RD) was investigated. The total concentrations of PCBs ranged from below method detection limit (M.D.L.) to 37.11×10(-3)mgkg(-1) dry weight (mean: 11.70×10(-3)mgkg(-1); median: 13.28×10(-3)mgkg(-1)), which was at a medium level compared with other cities around the world. In general, the levels of PCBs decreased from the center of Beijing city to the suburb, suggesting the increasing PCBs concentrations with the age of the urban area. For different types of land use, the highest level of PCBs was observed in CG soils which have the oldest age, and the homologue profiles were similar, which were predominated by lowly chlorinated congeners including di-, tri- and tetra-CBs. Principal component analysis indicated that local sources such as Aroclor 1016, 1242, and 1248 were important sources in addition to long-range transport of PCBs all over the world. Although the toxic equivalency (TEQ) concentrations of dioxin-like PCBs in all soil samples of Beijing were higher than those in other urban areas of China, they met the Canadian soil quality standard.

Several current-use, non-PBDE brominated flame retardants are highly bioaccumulative: evidence from field determined bioaccumulation factors

With the phaseout of brominated flame retardants (BFRs) polybrominated diphenyl ethers (PBDEs), some non-PBDE BFRs have prompted to be alternatives to the discontinued PBDEs. To assess the bioaccumulation potential of these chemicals, field bioaccumulation factors (BAFs) for several non-PBDE BFRs including hexabromocyclododecanes (HBCDs), 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE), pentabromotoluene (PBT), pentabromoethylbenzene (PBEB), and hexabromobenzene (HBB), were determined in the aquatic species from a natural pond in an electronic waste recycling site in South China. The log BAFs ranged 2.58-6.01, 3.24-5.58, 3.44-5.98, 2.85-5.98, 3.32-6.08, 2.04-4.77, 2.72-4.09 and 3.31-5.54 for α-HBCD, β-HBCD, γ-HBCD, ∑HBCDs, BTBPE, PBT, PBEB, and HBB, respectively. The log BAF values for HBCD isomers, BTBPE, and HBB were greater than 3.7 (corresponding BAF value 5000) in most of the investigated species, demonstrating their highly bioaccumulative properties. α-, β-, and γ-HBCDs, BTBPE, and HBB appeared comparable or had even greater BAFs compared to PBDE congeners with similar K(OW), suggesting that these BFRs may have a potentially high environmental risk. The BAFs for the given BFR compound were largely variable between species, due to the species-specific feeding ecology, trophic level, and metabolic capacity for these pollutants. Positive linear relationships between log BAF and log K(OW) (r² = 0.59, p = 0.04), and molecular weight (r² = 0.54, p = 0.06) of non-PBDE BFRs were observed in the species with low trophic level (Chinese mysterysnail), suggesting that the chemical's physicochemical properties also played key roles in the bioaccumulation processes.

Diurnal fluctuations in polybrominated diphenyl ether concentrations during and after a severe dust storm episode in Kuwait City, Kuwait

Concentrations of polybrominated diphenyl ethers (PBDEs) were quantified in four-hour integrated air samples obtained serially over a five day period in May 2007 in Kuwait City during and after a severe dust storm. The ∑PBDE concentrations ranged from 51 to 1307 pg m(-3) for the first two days of sampling and 20 to 148 pg m(-3) for the rest of the sampling period. The first two days of sampling occurred during a severe dust storm episode when the total suspended particulates (TSP) in air exceeded 1000 μg/m(3) with concentrations peaking during the day and decreasing at night. During this dust episode, the peak nighttime PBDE concentration was 30 times higher than the minimum daytime concentration. Although ∑PBDE concentrations peaked at night during the first two sampling days, the fluctuations in the BDE 47:99 ratio tracked changes in ambient temperature remarkably well, following a clear diurnal pattern. The fraction of congeners in the gas phase varied inversely with solar flux and was lower on days with a high number of hours of sunshine, suggesting that photolytic degradation of gas-phase PBDEs was occurring.

Bioaccumulation and distribution of polybrominated diphenyl ethers in marine species from Bohai Bay, China

Polybrominated diphenyl ethers (PBDEs) were analyzed in invertebrate and fish species collected from Bohai Bay, China in 2007 to 2008. The concentrations of the 16 detected PBDE congeners were in the range of 1.4 to 425 and 2.9 to 767 ng/g lipid for invertebrates and fish, respectively. The summed concentrations of the six major PBDE congeners (BDE-28, 47, 99, 100, 153, 154) (Σ(6)PBDEs) in fish were significantly higher than in invertebrates, while demersal fish concentrations were higher than pelagic fish. The congeners BDE-47, 99, and 100 contributed more in viscera or liver than in muscle, indicating that the metabolic capability of the viscera or liver is greater than that of muscle. The ratio of BDE-47/99 was relatively higher in fish than in invertebrate samples, suggesting a more developed metabolism capacity in fish. Polybrominated diphenyl ether congeners tend to accumulate in viscera or liver rather than in muscle. The fully brominated congener BDE-209 was detected in some species, suggesting that it can be accumulated by organisms. Uptake from sediment may be the major uptake pathway for most brominated PBDEs in benthic species.

Bioaccumulation behavior of polybrominated diphenyl ethers (PBDEs) in the freshwater food chain of Baiyangdian lake, north China

Polybrominated diphenyl ethers (PBDEs) are of great environmental concern due to bioaccumulation in different food chains. Trophodynamics of PBDEs in freshwater food chain is an important criterion for assessing their ecological risk. In the study, PBDEs were analyzed in sixteen aquatic species collected from Baiyangdian Lake, North China. The concentrations of nine PBDE congeners (BDE-28, -47, -66, -99, -100, -85, -153, -154, and -183) in aquatic organisms ranged from 3.4 to 160.2ng/g lipid weight. BDE-47 was the predominant PBDE congener in most samples except for river snails and swan mussels. BDE-209 was detected in 50% of biota samples, which indicated the bioavailability of BDE209. Correlation between lipid-normalized concentrations of PBDEs and trophic levels determined by stable isotope nitrogen technologies confirmed that PBDEs were biomagnified in the freshwater food chain. The trophic magnification factors (TMFs) ranged from 1.3 to 2.1 for PBDE congeners, greater than one, indicating the biomagnification potential for the PBDE congeners in the freshwater food chain. The relationship between TMFs and Log K(ow) (octanol-water partition coefficient) indicated that the phenomenon of trophic magnification for lowly brominated congeners was obvious in the freshwater food chain.

Bioaccumulation and biomagnification of polybrominated diphenyl ethers in a food web of Lake Michigan

Polybrominated diphenyl ethers are hydrophobic chemicals and can biomagnify in food chains. Little is known about the biomagnification of PBDEs in the Lake Michigan food web. Plankton, Diporeia, lake whitefish, lake trout, and Chinook salmon were collected from Lake Michigan in 2006 between April and August. Fish liver and muscle and whole invertebrates were analyzed for six PBDEs (BDE-47, 99, 100, 153, 154, and 209). Carbon and nitrogen stable isotope ratios (delta(13)C and delta(15)N) were also quantified in order to establish the trophic structure of the food web. Geometric means of Sigma PBDE concentrations in fish ranged from 0.562 to 1.61 microg/g-lipid. BDE-209 concentrations ranged from 0.184 to 1.23 microg/g-lipid in all three fish species. Sigma BDE-47, 99, and 209 comprised 80-94% of Sigma PBDE molar concentration. Within each fish species, there were no significant differences in PBDE concentrations between liver and muscle. The highest concentration of BDE-209 (144 microg/g-lipid) was detected in Diporeia. Based on analysis of delta(15)N and PBDE concentrations, BDE-47 and 100 were found to biomagnify, whereas BDE-209 did not. A significant negative correlation between BDE-209 and trophic level was found in this food web. Biomagnification factors were also calculated and again BDE-47 and 100 biomagnified between food web members whereas BDE-209 did not. Diporeia could be one of the main dietary sources of BDE-209 for fish in Lake Michigan; BDE-47 and 100 biomagnified within this food chain; the concentration of BDE-209 decreased at higher trophic levels, suggesting partial uptake and/or biotransformation of BDE-209 in the Lake Michigan food web.

Occurrence and levels of polybrominated diphenyl ethers (PBDEs) in recent sediments and marine organisms from Xiamen offshore areas, China

Surface sediments and porewater from 12 sites within Xiamen offshore areas and organisms from a heavily contaminated site Yuandang Lagoon were sampled and analyzed for eight polybrominated diphenyl ethers (PBDEs) congeners (-28, -47, -99, -100, -153, -154, -183 and -209). The total concentrations of eight PBDEs ( summation operator(8)PBDEs) and BDE-209 in sediments ranged from 0.27 to 76.54ng/g with an average of 16.31ng/g and from 0.10 to 70.11ng/g with an average of 14.94ng/g, respectively. Concentrations of summation operator(8)PBDEs in porewater ranged from 2.5 to 34.1ng/L, with a mean value of 15.3ng/L. In this study, the partition coefficients (log K(oc)(')) of PBDE congeners (without -209) were significantly correlated with their octanol-water partition coefficients (log K(OW)) (r(2)=0.74, P<0.01). summation operator(8)PBDE concentrations ranged from 0.33 to 1.26ng/g (lipid weight) in marine organisms, and PBDE congener patterns were significantly different between fish and clam, crab.

Polybrominated diphenyl ethers (PBDEs) in selected fish species from the southern Baltic Sea

This paper reports concentrations of seven polybrominated diphenyl ether (PBDE) congeners in selected fish species that were collected from the southern Baltic in the 2004-2006 period. Differences in concentrations of PBDEs among the fish species were observed. The mean summation Sigma(7)PBDE concentrations measured in herring (Clupeaharengus), sprat (Sprattus sprattus), and salmon (Salmo salar) samples were 1.2 ng g(-1) wet weight, 1.6 ng g(-1) wet weight, and 2.5 ng g(-1) wet weight, respectively. PBDE-47 was the prevalent congener in all the samples tested. PBDE concentrations in the herring samples tested in the current study were similar to those determined in herring sampled in the northern Baltic, but slightly lower in comparison with concentrations in fish from the Belgian North Sea. PBDE levels occurring in salmon sampled in the southern Baltic were lower than those measured in the northern and northeastern Baltic, but similar to levels determined in salmon from the central part of the Baltic Sea. The risk posed by consuming the fish tested in the current study was evaluated according to the Provisional Tolerable Weekly Intake (PTWI) value for PBDEs recommended by the European Food Safety Authority (EFSA).

Behavioral changes in aging but not young mice after neonatal exposure to the polybrominated flame retardant decaBDE

BACKGROUND

After several decades of commercial use, the flame-retardant chemicals polybrominated diphenyl ethers (PBDEs) and their metabolites are pervasive environmental contaminants and are detected in the human body. Decabrominated diphenyl ether (decaBDE) is currently the only PBDE in production in the United States.

OBJECTIVES

Little is known about the health effects of decaBDE. In the present study we examined the effects of neonatal decaBDE exposure on behavior in mice at two ages.

METHODS

Neonatal male and female C57BL6/J mice were exposed to a daily oral dose of 0, 6, or 20 mg/kg decaBDE from postnatal days 2 through 15. Two age groups were examined: a cohort that began training during young adulthood and an aging cohort of littermates that began training at 16 months of age. Both cohorts were tested on a series of operant procedures that included a fixed-ratio 1 schedule of reinforcement, a fixed-interval (FI) 2-min schedule, and a light-dark visual discrimination.

RESULTS

We observed minimal effects on the light-dark discrimination in the young cohort, with no effects on the other tasks. The performance of the aging cohort was significantly affected by decaBDE. On the FI schedule, decaBDE exposure increased the overall response rate. On the light-dark discrimination, older treated mice learned the task more slowly, made fewer errors on the first-response choice of a trial but more perseverative errors after an initial error, and had lower latencies to respond compared with controls. Effects were observed in both dose groups and sexes on various measures.

CONCLUSIONS

These findings suggest that neonatal decaBDE exposure produces effects on behavioral tasks in older but not younger animals. The behavioral mechanisms responsible for the pattern of observed effects may include increased impulsivity, although further research is required.

Stable isotope-guided analysis of congener-specific PCB concentrations in a Japanese coastal food web

Organisms collected from a coastal ecosystem in Japan were analyzed for concentrations of 205 polychlorinated biphenyls (PCBs) congeners; analyses were guided by delta(13)C and delta(15)N measurements. The regression slopes of log PCB concentration on delta(15)N value are regarded as indices of biomagnification in food webs. The slope (wet weight basis) of SigmaPCBs was +0.104; the slope (lipid weight basis) was close to zero. Lipid content increased from 0.06% in a primary producer to 8.32% in the highest trophic level consumer. Hence, biomagnification of SigmaPCBs (wet weight basis) can be attributed to increase of lipid content through the food web. For most of the congeners, the slopes (wet weight basis) exceeded those (lipid weight basis) by ca. 0.10. Slopes increased with increasing PCB chlorination levels between chlorine numbers 1-6; slopes decreased at higher chlorination levels. This decrease is likely caused by a decrease in membrane permeability with increasing molecular weight.

Bioaccumulation and trophic transfer of polybrominated diphenyl ethers (PBDEs) in biota from the Pearl River Estuary, South China

Two hundred and fifty-four biota samples (four species of invertebrates and ten species of fish) were collected from the Pearl River Estuary between 2005 and 2007 and one hundred and twenty four individual or composite samples were analyzed for polybrominated diphenyl ethers (PBDEs). The concentrations of PBDEs in organisms varied from 6.2 to 208ng/g lipid weight. This PBDE level was significantly lower than those collected in 2004, showing a decreasing trend of PBDEs in biota in the study area. Trophic magnification factors (TMFs) for nine BDE congeners were calculated with values ranging from 0.78 to 3.0. TMFs of BDE47, 66, 100, 99, 154, and 153 were statistically greater than one, indicating a biomagnifcation potential for these congeners. Significant positive correlations were also found between concentrations of the total PBDEs, BDE28, 47, 66, 100, 99, 154, and153 and lipid content in biota, indicating the that bioconcentration also played an important role in the accumulation of PBDEs. No correlation between trophic level and lipid content was found, suggesting that biomagnification was not the result of lipid content effect but indeed occurred. The concentration ratios of BDE99 to BDE100 were much lower in biota than that in water implying that potential congener-specific biotransformation of PBDEs occurred and influenced the biomagnification of BDE congeners.

Bioaccumulation of organochlorine pollutants in the fish community in Lake Arungen, Norway

Organochlorine pollutants in the major fish species (pike Esox lucius, perch Perca fluviatilis, and roach Rutilus rutilus) of Lake Arungen, Norway, were investigated after an extensive removal of large pike in 2004. The organochlorine pollutants detected in fish liver samples in 2005 were dichlorodiphenyltrichloroethane (DDTs), polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and heptachlor epoxide (HCE). DDTs were the dominant among all analyzed OCs. Sigma PCB and HCB, detected in fish from two clearly distinct trophic levels (prey and predators), give an indication of biomagnification. All OC concentrations in female pike were significantly lower compared to males, which might be due to the removal of high concentrations of pollutants in roe during spawning.

Organochlorines in the Vaccarès Lagoon trophic web (Biosphere Reserve of Camargue, France)

During a decade (1996-2006), ecotoxicological studies were carried out in biota of the Vaccarès Lagoon (Biosphere Reserve in Rhone Delta, France). A multicontamination was shown at all levels of the trophic web due to a direct bioconcentration of chemical from the medium combined with a food transfer. Here, the pollutants investigated were organochlorines, among which many compounds banned or in the course of prohibition (or restriction) (PCB, lindane, pp'-DDE, dieldrin, aldrin, heptachlor, endosulfan...) and some substances likely still used in the Rhone River basin (diuron, fipronil). The results confirmed the ubiquity of contamination. It proves to be chronic, variable and tends to regress; however contamination levels depend on the trophic compartment. A biomagnification process was showed. A comparison of investigation methods used in other Mediterranean wetlands provides basis of discussion, and demonstrates the urgent need of modelling to assess the ecotoxicological risk in order to improve the management of such protected areas.

Residues of polybrominated diphenyl ethers in frogs (Rana limnocharis) from a contaminated site, South China: tissue distribution, biomagnification, and maternal transfer

Environmental pollutants are suspected to be a cause of global declines in amphibian populations, but few data are available on the bioaccumulation of polybrominated diphenyl ethers (PBDEs) in amphibians. To examine the tissue distribution, biomagnification potential, and maternal transfer of PBDEs in frogs, eighteen PBDE congeners were measured in the muscle, liver, and egg tissues of rice frogs (Rana limnocharis) and insects collected from an electronic waste (e-waste) recycling site in South China. PBDE levels in the frogs ranged from 0.63 to 11.6, 4.57 to 56.2, and 10.7 to 125 ng/g wet wt in the muscles, livers, and eggs, respectively. The frogs exhibited a unique congener profile, compared to those in aquatic and terrestrial species, with BDEs 99, 153, 183, 209, and 47 as the dominant congeners, intermediating between aquatic and terrestrial species. Most of the PBDE congeners in general showed higher affinity to liver than to muscle tissue. Except for BDEs 28, 47, 66, 138, and 206, the average biomagnification factors (BMFs) for all PBDE congeners were greater than 1.0, providing clear evidence of their biomagnification from insects to frogs. A parabolic relationship between log BMFs and bromine atom numbers or log Kow of PBDEs was observed, with the maximum BMF values for PBDEs with 6 bromine atoms (or at a log K(ow) of approximately 8.0). Relatively higher levels of 3-MeO-BDE 47 were found in male frogs, suggesting that male frogs in the present study might have higher metabolic capacity for PBDEs compared to female frogs. The ratio of levels in egg/female liver, indicating mother-to-egg transfer capacity, increased with increasing bromine atom numbers up to 7 and then declined as the bromine atom numbers rose. This indicated that the physicochemical properties of the congeners (e.g., K(ow), molecular sizes, and structures), resulting in different affinities to transport proteins, might impact their maternal transfer in frogs.

Patterns of bioaccumulation of polybrominated diphenyl ether and polychlorinated biphenyl congeners in marine mussels

Marine mussels (Modiolus modiolus) and sediment from 14 stations near a municipal outfall and three reference locations were analyzed for polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) to evaluate and compare patterns of bioaccumulation of individual congeners between these two groups of chemicals. Of the 47 PBDEs and 209 PCBs analyzed, 34 PBDE and 153 PCB congeners or coeluting groups of congeners were detected in one or more matrices. The predominant PBDE congeners were BDEs 47, 99, 100, and 209, accounting for 80-90% of the total PBDEs in all matrices. PCBs and PBDEs exhibited a parabolic relationship of the biota-sediment accumulation factor (BSAF) versus the log octanol-water partition coefficient(Kow). Below Kow 10(5.5), BSAFs ranged between 1 and 3, reflecting approximate equilibrium between mussels and sedimentforthese relatively water soluble congeners. BSAFs increased with increasing Kow to maximum values of approximately 30-100 for congeners with Kow approximately 10(7) and then declined at higher Kow to a value of approximately 1 for BDE 209. BSAFs for PBDEs were generally 2- to 3-fold higher than those for PCBs of a similar Kow. The calculated BSAFs for PBDE congeners indicate that PBDEs have a pattern of bioaccumulative behavior in mussels similar to that of the PCBs, and that some PBDE congeners may be more bioaccumulative in mussels than PCBs.

Identification and evaluation of a novel heterocyclic brominated flame retardant tris(2,3-dibromopropyl) isocyanurate in environmental matrices near a manufacturing plant in southern China

A brominated flame retardant (BFR), hexabrominated heterocyclic tris-(2,3-dibromopropyl) isocyanurate (TBC), was identified,forthe first time, in the natural environment.The chemical was found in river water (2.33-163 ng/L), surface sediments (85.0 ng/g-6.03 microg/g dry weight (dw)), soils (19.6-672 ng/g dw), earthworm (9.75-78.8 ng/g dw), and carp samples (12.0-646 ng/g dw) from a factory-polluted area in southern China. It was found that TBC can strongly adsorb to organic material in sediment, and a trend of decreasing concentration with distance from the source in soil and earthworm samples, combined with calculated Kow (octanol-water partition coefficient) and Koa (octanol-air partition coefficient), suggests its potential ability to undergo regional transportation through dust deposition. Calculated results showed high Kow (log Kow = 7.37) and bioaccumulation factor (BAF) (log BAF = 4.30) of this BFR and indicate that TBC has semivolatile properties and bioaccumulation characteristic in certain biological species. Quantitative structure property relationships (QSPRs) modeling revealed that TBC has Koa (log Koa = 23.68) and Kaw (air-water partition coefficient) (log Kaw = -16.31) values several orders higher than those of other BFRs. The identification of this chemical additive further reminds us that the production and usage of heterocyclic BFRs may cause potential contamination to the surrounding environment

Persistent organic pollutants in two fish species of Percidae and sediment from the Sulejowski Reservoir in central Poland

Two predatory fish species, pikeperch and perch, and sediment from the Sulejowski Reservoir in Poland were analyzed for several classes of persistent organic pollutants. Polychlorinated biphenyls (PCBs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), heptachlor, and DDTs were measured in the fish muscles. In addition, the distribution and profile of PCBs in muscles, livers, and gonads was examined. In sediment, PCBs and polychlorinated dibenzo-p-dioxins (PCDDs) and furans (PCDFs) were analyzed. The main contaminant in the muscles of both species was p,p'- DDE reaching an average of 1072 and 694 ng g(-1) lipid in pikeperch and perch, respectively. SigmaPCBs, with an average concentration of 454 and 261 ng g(-1) lipid, respectively, were the second dominant contaminants. The two species differed in their PCB congener profile as a result of differences in feeding habits. Sediment PCDD/F concentrations ranged from 10.8 to 162.7 pg g(-1) dry mass, TEQ(PCDD/Fs) from 1.13 to 4.13 pg g(-1) dry mass, and the sum of indicator PCBs (SigmaPCB(7)) from 2.8 to 5.2 ng g(-1) dry mass. Biota-sediment accumulation factors (BSAFs) for SigmaPCB(7) were generally greater in pikeperch than in perch as a result of greater lipid content in the latter. Based on the contaminant levels in the sediment and fish, the Sulejowski Reservoir compares well with other, freshwater environments relatively uncontaminated with persistent organic pollutants.

Biomagnification of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls in a highly contaminated freshwater food web from South China

To evaluate the biomagnification extent of polybrominated diphenyls ethers (PBDEs) and polychlorinated biphenyls (PCBs) in a highly contaminated freshwater food web from South China, trophic magnification factors (TMFs) for 18 PBDE congeners and 53 PCB congeners were calculated. The TMF values ranged 0.26-4.47 for PBDEs and 0.75-5.10 for PCBs. Forty-five of 53 PCBs and BDEs 47, 100 and 154 had TMFs greater than one, suggesting their biomagnification in the present food web. The TMFs for PBDEs were generally smaller than those for PCBs with the same degree of halogenation, indicating a lower biomagnification potential for PBDEs compared to PCBs. For PCBs, it followed a parabolic relationship between TMFs and logK(OW) (octanol-water partition coefficient). However, this relationship was not significant for PBDEs, possibly due to the more complex behaviors of PBDEs in the food web (e.g., metabolism), compared to that of PCBs.

Ecotoxicological effects of mixed pollutants resulted from e-wastes recycling and bioaccumulation of polybrominated diphenyl ethers in Chinese loach (Misgurnus anguillicaudatus)

To understand potential ecotoxicological effects of electrical and electronic equipment waste (e-waste) recycling and polybrominated diphenyl ethers (PBDEs) bioaccumulation in loaches, a semi-field experiment using Chinese loach (Misgurnus anguillicaudatus) as experimental fish was performed. Larval loaches were kept in net-cage for three months in an e-wastes recycling site and a reference site in Southeastern China. There was significant difference of the survival rate between the loaches from the e-wastes recycling site (27%, 19/70) and from reference site (70%, 49/70). Histopathological responses were also found in all the livers examined in loaches from the e-wastes recycling site. These results showed that mixed pollutants resulted from e-wastes recycling led to ecotoxicological effects on loaches. The bioaccumulation of polybrominated diphenyl ethers (PBDEs), the main pollutants in e-waste, in loaches was also studied, the mean concentration of total PBDEs in sediment was 6726.17 ng/g wet weight and in water samples was 4.08 ng/L (dissolved phase). BDE 209 was the dominant congener in sediment and with relatively high concentration in water. Relatively low concentration of BDE 209 (less than 0.01% of total PBDEs) and high concentration of BDE47 (up to 39.34% of total PBDEs) were detected in loaches.

Biomagnification profiles of tributyltin (TBT) and triphenyltin (TPT) in Japanese coastal food webs elucidated by stable nitrogen isotope ratios

The measurement of organotins in the various biotas of coastal food webs with stable nitrogen isotope ratios (delta(15)N), which increase 3.4 per thousand per trophic level, can provide a biomagnification profile of organotins through food web. In this study, various biological samples were collected from three localities in Western Japan between 2002 and 2003 for analyses. Tributyltin (TBT) and triphenyltin (TPT) were still detected with a maximum of 99.5 and 8.7 ng wet weight g(-1), respectively. Unlike TBT, significant biomagnification of TPT through the food web (expressed by delta(15)N) was found in all three localities. The log transformed octanol-water partition coefficient (log K(ow)) of TPT of 2.11-3.43 was overlapped by, but was slightly lower than, that of TBT of 3.70-4.70. Thus, this study demonstrates that although these chemicals have a log K(ow) lower than 5, at least TPT undergoes significant biomagnification through the food web.

Anthropogenic and naturally occurring organobrominated compounds in two deep-sea fish species from the Mediterranean Sea

Polybrominated diphenyl ethers (PBDEs) were investigated in 15 composite liver samples from two deep-sea fish species, the hollowsnout grenadier (Trachyrinchus trachyrinchus, TT) and the roughsnout grenadier (Coelorhynchus coelorynchus, CC). Mean concentrations of sum tri- to hepta-BDEs were higher in CC species than in the TT species (16.9 vs. 4.5 ng/g lipid weight (lw), respectively). BDE 47 and BDE 100 were the major congeners in both species. Methoxylated PBDEs (MeO-PBDEs), reported as being naturally produced in marine environments, were also measured in all samples. Similar to those of PBDEs, mean concentrations of sum MeO-PBDEs (sum congeners 2'-MeO-BDE 68 and 6-MeO-BDE 47) were higher in the CC species (28.9 vs 6.6 ng/g lw, respectively). Interestingly, polybrominated hexahydroxanthene derivatives (PBHDs) had the highest contribution to the total load of organobromines in the deep-sea fish samples. Contraryto those of PBDEs and MeO-PBDEs, the mean concentrations of PBHDs were higher in the TT species (7040 vs. 530 ng/g lw, respectively). Furthermore, an unusual profile was seen in the TT species, for which a tetrabrominated BHD isomer was the predominant isomer (up to 98% of the sum PBHDs). This differs from the profiles of PBHDs dominated by a tribrominated BHD isomer reported until now in the literature. The mixed halogenated monoterpene (MHC-1) and 2,4,6-tribromoanisole (TBA) were detected as well, albeit at lower concentration (<5 ng/g lw), supporting the hypothesis that these two natural products are rather abundant in shallow waters.

Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in 0+ juvenile cyprinids and sediments of the Po River

PBDE and PCB content has been determined in 0+ bleak (Cyprinus alburnus), nase (Chondrostoma soetta), gudgeon (Cyprinus gobio), chub (Cyprinus cephalus), and barbel (Barbus sp.) as well as in bed sediments sampled from the River Po upstream and downstream of the confluence of a tributary draining a highly industrialized and urbanized subbasin. Both groups of chemicals were present at higher levels in fish and sediments downstream from the confluence. In addition, whole-body concentrations of PBDEs and PCBs were different among species despite the young specimen age. The fact that PBDEs and PCBs were higher in benthivorous versus planktivorous fish, as well as in carnivorous versus herbivorous species, suggests that feeding behavior is a major controlling factor that may help differentiate the accumulation levels of 0+ juveniles. Of the five species, the pelagic/planktivorous cyprinid bleak (C. alburnus) showed the lowest concentrations (111 ng PBDE/g lipid weight [l.w.], 2016 ng PCB/g l.w.), whereas the benthic dweller and feeder barbel (Barbus sp.) had the highest concentrations of both groups of chemicals (259 ng PBDE/g l.w., 4785 ng PCB/g l.w.). The rank order of species contamination was essentially stable upstream and downstream from the tributary, and the congener contribution of PBDEs was also similar. In general, BDE-47 was the dominant congener, followed by BDE-100, -154, -153, and -28. BDE-209 dominated the PBDE congener profiles of sediments but was not found in any fish sample. Conversely, an unidentified hexa-BDE congener, which was not detected in sediments, was found in all fish species. The levels of PBDEs and PCBs determined in adult goby (Padogobius martensii), a small demersal predator also examined in the same river stretches, provided additional useful insights with which to interpret results.

Polychlorinated biphenyls in contaminated soil samples evaluated by GC-ECD with dual-column and GC-HRMS

We present and compare results obtained from the analysis of polychlorinated biphenyls (PCBs) of a limited number of contaminated soil samples collected in three areas of Basilicata region (south of Italy). The levels of PCBs were evaluated by using two analytical methods: (i) parallel dual-column gas-chromatography with dual electron capture detectors (GC-ECD) and (ii) gas-chromatography coupled to high-resolution mass spectrometry (GC-HRMS) via electron impact ionization (EI) in the multiple ion monitoring mode (MIM, two ions per compound). Two extraction methods prior to sample cleanup were also examined: microwave-assisted extraction (MAE) and ultrasonic-assisted extraction (UAE). The MAE was the extraction procedure adopted using acetone/n-hexane (1:1, v/v) as it is mainly characterized by higher sample throughput and allowed reduced consumption of organic solvents. While extraction and analysis of spiked soil samples showed the applicability of both methods, systematic differences between the results were obtained for the sum of PCBs as a result of some non-detected congeners by GC-ECD compared with GC-HRMS. Indeed, high resolution MS using EI mode (electron energy 40eV) with a resolving power of 10,000 provides additional information about the contamination pattern. The GC-ECD screening of 11 soil samples led to just one sample non-compliant to as it was close to the guide value for soils fixed by the Italian legislation (i.e., 60ppb for private or urban soil). Using GC-HRMS, the amount of all PCBs found ranged from 5.4 to 127ppb with five soil samples non-compliant to the guide value. The number of identified congeners ranged from 1 to 9 and 9 to 18 using dual-column GC-ECD and GC-HRMS, respectively.

Biomagnification of organic pollutants in benthic and pelagic marine food chains from the Baltic Sea

The trophic transfer of organic pollutants with varying physical chemical properties was determined in both a pelagic and benthic food chain using delta 15N as a continuous variable for assessing trophic levels. The trophic transfer of organic pollutants through the entire food chain in terms of food chain magnification factors (FCMFs) was quantified from the slope of the regression between ln [concentration] and delta 15N. Organic pollutants with statistically significant FCMFs >1 were considered to biomagnify within the food chain, whereas those with FCMFs <1 were considered to trophically dilute. Statistically significant FCMFs >1 were found for PCB congeners and organochlorine pesticides in the Baltic food chains whereas statistically significant FCMFs <1 were found for PAHs and PCNs due to trophic dilution resulting from metabolism. FCMFs were generally greater in the pelagic food chain than in the benthic food chain. However, estimated FCMFs for the benthic food chain are likely in error, as the delta 15N method suggested a food chain structure which was not consistent with the known dietary patterns of the species. Biomagnification factors (BMFs) were additionally calculated as the ratio of the lipid normalized concentrations in the predator and prey species with adjustment for trophic level and were generally consistent with the FCMFs with BMF >1 for PCBs and organochlorines.

Polybrominated diphenyl ethers (PBDEs) in biota representing different trophic levels of the Hudson River, New York: from 1999 to 2005

It has been hypothesized that a principal route of human exposure to polybrominated diphenyl ethers (PBDEs), used as flame retardants, is through fish consumption. Between 1999 and 2005 PBDE-47, -99, -100, -153, and -154 were analyzed in 3797 biological samples of 33 species of the Hudson River, New York. Approximately 98.4% of the samples contained PBDEs between 0.5 and 37 169 ng g(-1) lipid, with a median concentration of 772 ng g(-1) lipid. Yearly median sigmaPBDE concentrations fluctuated. Samples from river miles 112 and 153 contained higher sigmaPBDEs than those from other locations of the river. The 7-year median sigmaPBDE concentrations were the highest in large carnivorous fishes and the lowest in insects. The median abundance of congener PBDE-47 decreased from 80% to 63% with decreasing levels of sigmaPBDEs in the samples, while an increase from 2% to 23% was observed for PBDE-99. The median abundance of other congeners did not change with concentrations of sigmaPBDEs. Positive-, negative-, and no-correlation between sigmaPBDE concentrations and fish weight were observed for different species and for the same species from different locations of the river. The sources of PBDE contamination, diet, metabolic activity, and sediment chemistry might affect the levels of PBDEs in a fish.