Distribution patterns of nitrobenzenes and polychlorinated biphenyls in water, suspended particulate matter and sediment from mid- and down-stream of the Yellow River (China)

Samples of water, suspended particulate matter (SPM) and sediment were collected from mid- and down-stream of the Yellow River. The distribution and concentration of 10 nitroaromatic compounds and polychlorinated biphenyls (PCBs) were extensively studied. The total concentration of 10 nitrobenzenes (SigmaNBs) varied from 0.269 to 9.052 microg l(-1) in water, from 2.916 to 164.4 microg kg(-1) dry weight in SPM, and from 0.954 to 14.72 microg kg(-1) dry weight in sediment. PCBs associated with the sediments, measured as the summed responses of Aroclor 1242, 1248, 1254, 1260 (in comparison to those of a standard 1:1:1:1 mixture), were found to be in the range of non-detectable to 5.98 microg kg(-1). In the samples collected, various PCB congeners showed similar distribution characteristics with congeners containing 3-5 chlorine atoms accounting for more than 96.4% of total PCB. In most of the samples, PCB concentrations occurred in the order: TetraCB > TriCB > PentaCB. Levels of SigmaNBs in the Yellow River were relatively low in comparison with values reported from other river and marine systems, and PCB levels were comparatively low. Relative to the PCBs, SigmaNBs showed significantly more difference among the various stations, presumably due to the influence of different pollution sources. No obvious correlation was observed between the pollutant concentrations and either the TOC or the grain size of the sediments.     

Effect of mono-ortho and di-ortho substituted polychlorinated biphenyl (PCB) congeners on leopard frog survival and sexual development

We tested the effect of mono-ortho and di-ortho PCB congeners on northern leopard frog (Rana pipiens) hatching success, survival and sexual development. Embryos and tadpoles were exposed to two levels (0.5 and 50 microg/l) of two PCBs. PCBs 101 and 70 were selected because they were present in amphibians collected in the Fox River-Green Bay ecosystem and they have the theoretical structural requirements to be able to bind to the estrogen receptor and mediate estrogenic responses. The exposure of leopard frog embryos and tadpoles to PCB 70 and 101 did not significantly affect hatchability, survival, deformities or growth. There were significant departures from the expected 50:50 sex ratio in tadpoles/froglets exposed to PCB 101 and PCB 70. In all the cases of significant departure, the bias was towards higher number of females. Decrease in the proportion of male gonads and increase in the proportion of intersex gonads were observed with increasing PCB tissue concentrations. The effects of PCB congeners on sexual differentiation occur at concentrations higher than observed in frogs in the Fox River/Green Bay ecosystem.     

Concentration of bioactive compounds in mussels Mytilus galloprovincialis as an indicator of pollution

The polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organotins were analyzed in mussels Mytilus galloprovincialis from polluted and unpolluted sites from Mokpo Bay, Korea. The total PAH's concentrations (10(-3)mgkg(-1)) measured by GC-MS were in the range from 31+/-23 to 1+/-1. Among the eight PAHs the predominant ones were fluoranthene, phenanthrene and pyrene and accounted approximately 63% of the total PAHs. Among the four detected PCBs the highest content was of PCB 153, which accounted about 47% of the total PCBs. The main organotin compounds were dibutyltindichloride (DBT) and tributyltinchloride (TBT) and their composition was approximately 33% and 24%. PAHs, PCBs and organotins were found only in the mussels from polluted site. The antioxidant activity by ABTS [2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid)] test was higher in mussels from polluted than from unpolluted sites (P<0.05). It was found a correlation between the determined compounds (PAHs, PCBs and organotins) and the antioxidant activity of the mussel tissue from polluted site and the correlation coefficients were 0.96, 0.92 and 0.80, respectively. Such correlation can be explained by the properties of mussels. Since the mussel cell wall and tissues are hydrophobic, they can concentrate a number of hydrophobic pollutants like PAHs and PCBs from the marine environment by solubility rules. On the other hand, proteins are lipophilic compounds having antioxidant properties. Certain amino acid residues and thiol (-SH) groups, contained in proteins, respond to the ABTS antioxidant activity assay. Thus there may be a correlation between the total antioxidant activity of the organism and the PAH-PCB pollutants which were concentrated from its environment. The studied properties of mussels from polluted site can be used as an additional indicator of pollution.     

Occurrence of PAHs, PCBs and organochlorine pesticides in the Tonghui River of Beijing, China

Tonghui River, a typical river in Beijing, People's Republic of China, was studied for its water and sediment quality, by determining the levels of 16 polycyclic aromatic hydrocarbons (PAHs), 12 polychlorinated biphenyls (PCBs) and 18 organochlorine pesticides in water and sediment samples. Total PAHs, PCBs and organochlorine pesticides concentrations in water varied from 192.5 to 2651 ng/l, 31.58-344.9 ng/l and 134.9-3788 ng/l, respectively. The total PAHs, PCBs and organochlorine pesticides concentrations in surficial sediments were 127-928 ng/g, 0.78-8.47 ng/g and 1.79-13.98 ng/g dry weight, respectively. The results showed that the concentration of these selected organic pollutants in sediment was higher than those in surface water. It may be due to the fact that organic hydrophobic pollutants tend to stay in the sediments. The PAHs were dominated by 2-, 3-ring components in water samples and by 3- and 4-ring compounds in sediment. For organochlorines, alpha-HCH, delta-HCH, Heptachlor, Endosulfan II, DDT are the major organochlorine pesticides in water while Heptachlor, Dieldrin and DDE composed of 95% of total organochlorine pesticides in sediment. For HCHs (HCHs=alpha-HCH+beta-HCH+gamma-HCH+delta-HCH), the predominance of alpha-HCH of total HCHs were clearly observed in water and sediment. PCB18, PCB31 and PCB52 were predominant in water, on average these compounds collectively accounted for 67% of total PCBs. But in sediment, the predominant compounds were PCB28, PCB31 and PCB153, which accounted for 71% of total PCBs in sediment. The levels of micro pollutants in our study areas were compared with other studies.     

Atmospheric deposition of polycyclic aromatic hydrocarbons to Izmit Bay, Turkey

Wet deposition and dry deposition samples were collected in an urban/industrialized area of Izmit Bay, North-eastern Marmara Sea, Turkey, from September 2002 to July 2003. The samples were analyzed for sixteen polycyclic aromatic hydrocarbon (PAH) compounds by using HPLC-UV technique. Wet and dry deposition concentrations and fluxes of PAHs were determined. The results showed that PAH concentrations were high because of industrial processes, heavy traffic and residential areas next to the sampling site. Total dry deposition flux of the fifteen 3-6 ring PAHs was 8.30 microg m(-2)day(-1), with a range of 0.034-1.77 microg m(-2)day(-1). The total wet deposition flux of the fifteen 3-6 ring PAHs was 1716 microg m(-2) 11 month(-1), with a range of 10-440 microg m(-2) 11 month(-1). Significant seasonal differences were observed in both types of deposition samples. The winter fluxes of total PAHs were 1.5 and 2.5 times greater than those of the warm period for wet and dry deposition samples, respectively. Factor analysis of dry deposition samples and back trajectory analysis of wet deposition samples were also used to characterize and identify the PAH emission sources in this study.     

Polychlorinated biphenyls in Narragansett Bay surface sediments

Polychlorinated biphenyls (PCBs) were evaluated in 41 surface sediments collected from Narragansett Bay, RI in 1997-1998. Highest concentrations of total PCBs (1760 ng/g) were in rivers at the head of the bay and the values decreased southward toward the mouth of the bay, with elevated concentrations in some of the coves. The PCB levels in approximately 43% of the samples exceeded the effects range median (ERM) guideline [Environ. Manage. 19 (1995) 81] indicating possible adverse biological effects at these stations. Principal component analysis (PCA) of the surface sediment PCBs separated the Taunton River samples from the rest of the samples. This result suggests that this river has a different PCB composition and sources than the other areas investigated. It also showed that this river has a limited influence on other bay stations as the adjacent samples downstream did not have the same chemical signature. Congener ratios derived from the PCA were useful in distinguishing stations that had different sources of PCBs than the bulk of the bay sediments. Although Aroclor 1268 and 1270 accounted for <1% of all PCB production, their major components, CB206 and CB209, account for 3-6% of the CBs in most bay samples. This may reflect more local use of these Aroclor mixtures and/or be indicative of their relative stability, compared to less chlorinated mixtures. Using linear alkyl benzenes (LABs) as a marker for sewage derived PCBs suggested that up to 95% of the PCBs at the most contaminated sites in the Seekonk, Providence, and Taunton Rivers were sewage derived. This analysis also showed that there is a high background level (167 ng/g) of PCBs in the Seekonk and Providence River, while the Taunton River had a relatively low background level (23.7 ng/g). At the furthest stations south in the Providence River, the sewage derived PCBs only accounted for 23% of the total which suggests that PCB associated with sewage particles are rapidly deposited and are therefore not the most significant source of these compounds to the lower reaches of Narragansett Bay.     

Chloroaromatic pollutants in mussels incubated in two finnish watercourses polluted by industry

Concentrations of different chlorinated compounds were measured in mussels incubated in two polluted watercourses, a river (the River Kymijoki) and a lake (Lake Vanaja) for four weeks in summer 1995. The sum concentrations of polychlorinated phenols (PCP) and biphenyls (PCB) were both about 1 μg/g lipid weight (lw) in Lake Vanaja mussels, while in the River Kymijoki mussels PCPs were non-detectable and PCBs were measured 120 ng/g lIw. The concentrations of toxic polychlorinated dibenzo-p-dioxin (PCDD) and dibenzofuran (PCDF) congeners ranged between <17 and 370 pg/g Iw in Lake Vanaja mussels and between <38 and 11,000 pg/g lw in the River Kymijoki mussels. Polychlorinated diphenyl ethers (PCDE) were detected in the mussels incubated in the River Kymijoki (0.4–1.1 ng/g Iw), but not in those incubated in Lake Vanaja. Polychlorinated phenoxyanisoles (PCPA) were measured 33 ng/g lw and polychlorinated phenoxyphenols (PCPP) 300 ng/g lw in the mussels incubated in the River Kymijoki. PCPAs were also detected in reference samples, which were sediment and pike from the River Kymijoki and Baltic salmon, seal and white-tailed sea eagle.     

Concentrations and accumulation patterns of organochlorine contaminants in the blubber of harbour porpoises, Phocoena phocoena, from the coast of Newfoundland, the Gulf of St Lawrence and the Bay of Fundy/Gulf of Maine

Concentrations of 99 organochlorine compounds were measured in the blubber of 196 harbour porpoises, Phocoena phocoena, killed in commercial gill net fisheries in the western North Atlantic. PCBs and chlorinated bornanes (CHB) were the dominant contaminants in all porpoises. Mean concentrations (with standard deviations) of PCBs and CHBs from the three regions were as follows: Bay of Fundy/Gulf of Maine, PCB males 17.3 +/- 11.2 microg/g, PCB females 11.4 +/- 4.8 microg/g, CHB males 11.5 +/- 6.6 microg/g, CHB females 8.4 +/- 5.3 microg/g; Gulf of St Lawrence, PCB males 10.6 +/- 5.4 microg/g, PCB females 7.2 +/- 3.9 microg/g, CHB males 14.1 +/- 8.8 microg/g, CHB females 9.0 +/- 6.3 microg/g; southeast Newfoundland, PCB males 5.2 +/- 2.5 microg/g, PCB females 5.5 +/- 4.4 microg/g, CHB males 7.0 +/- 2.2 microg/g, CHB females 5.5 +/- 3.0 microg/g. The relative composition of the major contaminant groups found in male and female harbour porpoise blubber from the three locations varied. In order of decreasing concentration, porpoises from Fundy/Maine had PCBs > CHB > DDT > chlordanes (CHL), whereas Gulf of St Lawrence and Newfoundland porpoises had CHB > PCB > DDT > CHL. Significant increases with age were observed for most contaminants in male harbour porpoises, and significant decreases were observed in females. Females lose about 15% of their contaminant burden per birth. PCB and DDT levels in porpoises from the Bay of Fundy are significantly lower than those recorded in the 1970s.     

Integrated biomarker response index as a useful tool for environmental assessment evaluated using transplanted mussels

Mytilus galloprovincialis mussels from a clean area were transplanted from 2003 to 2005 to several stations in the Bay of Cannes (North-Western Mediterranean Sea) including a site considered as reference, for 1 month at the end of spring (May). Several biomarkers (AChE, GST and CAT activities, TBARS and MT concentrations) were measured in the transplanted organisms. The concentrations of metals (Cd, Cu and Zn) were determined in the transplanted mussels, PAH and PCB analyses were performed in the mussels caged in 2004. The integrated biomarker response (IBR) was calculated; pollutant concentrations in mussels were displayed as star plots and compared to IBR star plots. Visualization was thus possible between sites for comparison with exposure conditions. Results demonstrated that the mussels from the Old harbour site (VP) are characterized by elevated copper and PCB concentrations, those from Canto harbour (PC) presented high PCB contents and those from the mouth of the Siagne River (ES) high PAH concentrations compared to the animals transplanted in the reference site (IL). In 2003, there was a visual correlation between the copper gradient measured in the transplanted mussels and the IBR variation. In 2004, the agreement between the copper gradient and the PCB gradient measured in the caged mussels and the IBR variation was good whereas the PAH gradient did not seem to contribute to the IBR demonstrating that the chosen biomarkers did not respond to PAHs. In 2005, IBR showed that other contaminants, not measured might be present in VP, PC and ES compared to the reference station (IL).     

Polybrominated diphenyl ethers (PBDEs) in marine fish and blue mussels from southern Greenland

Levels of polybrominated diphenyl ethers (PBDEs) have not previously been reported in Greenland. In this study shorthorn sculpins (Myoxocephalus scorpius) were sampled at three locations in southern Greenland; Usuk (no population), Igaliko (population 40) and Qaqortoq (population 3200). Furthermore uvak (Gadus ogac), spotted wolffish (Anarhichas minor), starry ray (Raja radiata), and blue mussels (Mytilus edulis) were collected at Usuk. Pooled samples of fish liver and blue mussel were analysed for lower brominated PBDEs (BDE-47, BDE-99, BDE-100 and BDE-153). The highest PBDE levels were found in Qaqortoq followed by Igaliko and Usuk. The measured sum PBDE concentrations in shorthorn sculpin collected at Qaqortoq, Igaliko and Usuk, were 8.2, 3.1 and 2.1 all in units of microg kg(-1) wet weight. In female and male uvak collected at Usuk PBDE levels of 7.1 and 12.0 microg kg(-1) wet weight were measured, while the concentrations were 1.2 microg kg(-1) in spotted wolffish, 1.4 microg kg(-1) in starry ray and 0.11 microg kg(-1) in blue mussels from the same locality all measured on a wet weight basis. The highest concentrations were measured in uvak, a top-predator on fish indicating that PBDEs are biomagnifying. The level of tetra-hexa BDEs is 15-24 times lower than PCB levels measured in the same samples, except for shorthorn sculpin collected at Qaqortoq, where the level of PBDEs was 40 times lower than the level of PCBs. The high concentration of PCBs relative to PBDEs in shorthorn sculpin collected at Qaqortoq signifies a local emission of PCBs, which is higher than the local emission of PBDEs.     

Residues of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides in organically-farmed vegetables

The residues of polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in soils from organic farms and their uptake by four varieties of organic-produced potatoes and three varieties of organic carrots from England were investigated. Samples of the soils, crop peels and cores were all Soxhlet-extracted in triplicate, cleaned up by open-column chromatography and analysed by a multi-residue analytical method using gas chromatography with mass selective detection. The concentrations of PAHs, PCBs and OCPs in soils from organic farms ranged from 590+/-43 to 2301+/-146 microg/kg, 3.56+/-0.73 to 9.61+/-1.98 microg/kg and 52.2+/-4.9 to 478+/-111 microg/kg, respectively. Uptake by different crop varieties were 8.42+/-0.93 to 40.1+/-4.9 microg/kg sigmaPAHs, 0.83+/-0.19 to 2.68+/-0.94 microg/kg sigmaPCBs and 8.09+/-0.83 to 133+/-27 microg/kg sigmaOCPs. Residue uptake from soils depended on plant variety; Desiree potato and Nairobi carrot varieties were more susceptible to PAH contamination. Likewise, uptake of PCBs and OCPs depended on potato variety. There were significant positive correlations between the PCB and OCP concentrations (P<0.05) in soils and carrots but no significant correlation was found between the concentrations of any contaminants in soils and potatoes. Peeling carrots and potatoes was found to remove 52-100% of the contaminant residues depending on crop variety and the properties of the contaminants. Soil-crop bioconcentration factors (BCFs) decreased with increasing logK(ow) for PAHs up to about 4.5 and for PCBs up to about 6.5, above which no changes were discernible for either class of contaminants. No relationship was observed between soil-crop BCFs and logK(ow) for OCPs, most likely because their concentrations were low and variable.     

Polychlorinated biphenyls in surface sediments of Yueqing Bay, Xiangshan Bay, and Sanmen Bay in East China Sea

The spatial distribution and source of polychlorinated biphenyls (PCBs) in 30 surface sediments of Yueqing Bay, Xiangshan Bay, and Sanmen Bay in Eastern China were analysed. Total concentrations of PCBs ranged from 9.33 to 19.60 ng g⁻¹ dry weight for all the sampling stations. The observed PCB levels were lower than those in areas of high urbanisation or contamination in the bay. Low-chlorinated PCBs, dominated by tri-PCB, were identified as the prevalent contaminate of surface sediments, and the top three PCB congeners were lighter chlorinated congeners (PCB 8, PCB 18 and PCB 28). These results were in agreement with the fact that tri-PCB compounds are the dominant contaminants in China. The result of the principal component analysis revealed that all samples were similar in composition to Aroclor 1242, suggesting they might originate from electrical capacitors and transformers. The levels of PCBs were significantly correlated with the total organic carbon in the sediments.     

Polychlorinated biphenyls (PCBs) and Polybrominated Diphenyl Ethers (PBDEs) in surface sediments from Monastir Bay (Tunisia,Central Mediterranean): Occurrence,distribution and seasonal variations

An assessment of PCB and PBDE contamination of surface sediments in Monastir Bay was carried out in two contrasted seasons of the year. Samples were collected from 5 sites and analyzed for the ∑₇ marker PCBs (i.e. PCBs 28, 52, 101, 118, 138, 153 and 180) and ∑₄ PBDE congeners (PBDEs 47, 99, 119 and 153) by GC/ECD. Concentrations of both PCBs and PBDEs showed seasonal variations. PCB concentrations were in the range of 3.1–9.3 ng g⁻¹ and 1.1–8.1 ng g⁻¹ in wet and dry season respectively, and sediments were considered moderately contaminated with PCBs. All PCBs analyzed were detected in surface sediments. PCB 153 and 52 congeners showed the highest relative abundance in both winter and summer. PBDE concentrations ranged from not detect to 0.1 ng g⁻¹, with only BDE-47 congener detected in sediments and only in winter. Analysis of spatial and seasonal variations indicated that PCB distribution is governed by hydrodynamics and temporal variability of inputs. While the PCB contamination appeared to be mainly land-based, PBDEs are suspected to originate from atmospheric deposition.     

Organochlorine,PCB, PAH,and metal concentrations in eggs of loggerhead sea turtles (Caretta caretta) from northwest Florida,USA

Abstract

Composite samples of unhatched and physically unaltered loggerhead sea turtle, Caretta caretta, eggs collected from 20 nests along northwest Florida were analyzed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and metals. Chemical analyses revealed that turtle eggs contained detectable amounts of metals, PAHs, and PCBs. Only one OCP, p, p'‐DDD, was detected, and its presence was restricted to eggs from two nesting sites. None of the PCB concentrations exceeded the Food and Drug Administration's (FDA) action limit. Concentrations of dioxin‐like PCB congeners, 105, 118, and 126, and total PCBs were also detected and are contributors to the toxic burden of loggerhead sea turtle eggs. Concentrations of PAHs, 1,2,5,6‐dibenzanthracene, 1‐methyl naphthalene, Cl‐naphthalene and naphthalene were variable at nesting sites. Comparison of mean metal burdens in eggs from different beaches suggested that no uniform geographic gradients exist. Presence of OCPs, PCBs, PAHs and metals and their additive or synergistic toxicity is a concern to loggerhead sea turtle eggs; however, additive or synergistic impacts for loggerhead sea turtles are largely undocumented.     

Organochlorine, PCB, PAH, and metal concentrations in eggs of loggerhead sea turtles (Caretta caretta) from northwest Florida, USA

Composite samples of unhatched and physically unaltered loggerhead sea turtle, Caretta caretta, eggs collected from 20 nests along northwest Florida were analyzed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and metals. Chemical analyses revealed that turtle eggs contained detectable amounts of metals, PAHs, and PCBs. Only one OCP, p,p'-DDD, was detected, and its presence was restricted to eggs from two nesting sites. None of the PCB concentrations exceeded the Food and Drug Administration's (FDA) action limit. Concentrations of dioxin-like PCB congeners, 105, 118, and 126, and total PCBs were also detected and are contributors to the toxic burden of loggerhead sea turtle eggs. Concentrations of PAHs, 1,2,5,6-dibenzanthracene, 1-methyl naphthalene, C1-naphthalene and naphthalene were variable at nesting sites. Comparison of mean metal burdens in eggs from different beaches suggested that no uniform geographic gradients exist. Presence of OCPs, PCBs, PAHs and metals and their additive or synergistic toxicity is a concern to loggerhead sea turtle eggs; however, additive or synergistic impacts for loggerhead sea turtles are largely undocumented.     

Impacts of urbanization on surface sediment quality: evidence from polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) contaminations in the Grand Canal of China

Introduction

Organic pollutants, especially synthetic organic compounds, can indicate paces of anthropogenic activities. Effects of urbanization on polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) distributions in surface sediment were conducted in urban sections of the Grand Canal, China, consisting of a four-level urbanization gradient.

Materials and methods

The four-level urbanization gradients include three countryside towns, two small-size cities, three medium-size cities, and a large-size city. Diagnostic ratio analysis and factor analysis?Cmultiple linear regression model were used for source apportionment of PAHs. Sediment quality guidelines (SQGs) of USA and Canada were employed to assess ecological risks of PAHs and PCBs in surface sediments of the Canal.

Results and discussion

Ranges of PAH and PCB concentrations in surface sediments were 0.66?C22?mg/kg and 0.5?C93???g/kg, respectively. Coal-related sources were primary PAH sources and followed by vehicular emission. Total concentration, composition, and source apportionment of PAHs exhibited urbanization gradient effects. Total PCB concentrations increased with the urbanization gradient, while total PAHs concentration in surface sediments presented an inverted U Kuznets curve with the urbanization gradient. Elevated concentrations of both PAHs and PCBs ranged at effect range low levels or interim SQG, assessed by USA and Canadian SQGs.

Conclusions

PAHs and PCBs in surface sediments of the Grand Canal showed urbanization gradient effects and low ecological risks.     

Organochlorine pesticides and polychlorinated biphenyls in California sea lions

Concentrations of polychlorinated biphenyls (PCBs), DDTs, chlordanes, HCHs, hexachlorobenzene (HCB), dieldrin, heptachlor epoxide, tris(4-chlorophenyl)methane (TCPMe), and tris(4-chlorophenyl)methanol (TCPMOH) were measured in the blubber of California sea lions (Zalophus californianus) collected in 2000. DDTs were the most predominant contaminants, followed by PCBs, chlordanes, TCPMe, HCHs, TCPMOH, dieldrin, and heptachlor epoxide. Concentrations of PCBs and DDTs varied from a few microg/g to several hundreds of microg/g on a lipid weight basis. Concentrations of DDTs have declined by an order of magnitude over the last three decades in California sea lions; nevertheless, the measured concentrations of PCBs and DDTs in California sea lions are still some of the highest values reported for marine mammals in recent years. Concentrations of organochlorines were highly correlated with one another. Concentrations of PCBs and DDTs in the blubber of gray whale, humpback whale, northern elephant seal, and harbor seal, and in the adipose fat of sea otter, were lower than the levels found in California sea lions, and were in the range of a few to several microg/g on a lipid weight basis.     

Environmental assessment of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Santander Bay,Northern Spain

Samples of intertidal surface sediments (0-2 cm) were collected in 17 stations of the Santander Bay, Cantabric Sea, Northern Spain. The concentrations of polycyclic aromatic hydrocarbons (PAHs), 16, were analysed by HPLC and MS detection. Surface sediments show a good linear correlation among the parameters of the experimental organic matter evaluation, where total carbon (TC) and loss on ignition (LOI) are approximately 2.5 and 5 times total organic carbon (TOC). A wide range of TOC from 0.08% to 4.1%, and a broad distribution of the sum of sigma16PAHs, from 0.02 to 344.6 microg/g d.w., which can be correlated by an exponential equation to the TOC, has been identified. A qualitative relationship may be established between the industrial input along the rivers and the concentration of sigma6PAHs in the sediments of the estuaries: Boo estuary (8404-4631 microg/g OC), Solia-San Salvador estuaries (305-113 microg/g OC) and Cubas estuary (31-32 microg/g OC). This work shows a dramatic change in the spatial distribution in the concentration of PAHs of intertidal surface sediments. The left edge of the Bay has the main traffic around the city and the major source of PAHs is from combustion processes and estuarine inputs, leading to medium values of PAHs in the sediments; the right edge of the Bay has much lesser anthropogenic activities leading to lower values of PAHs in sediments. The distribution of individual PAHs in sediments varies widely depending on their structure and molecular weight; the 4-6 ring aromatics predominate in polluted sediments due to their higher persistence. The isomer ratio does not allow any clear identification of the PAHs origin. Environmental evaluation according to Dutch guidelines and consensus sediment quality guidelines based on ecotoxicological data leads to the same conclusion, sediments in the Santander Bay show a very different environmental quality depending on the spatial position from heavily polluted/medium effects to non-polluted/below threshold effects. These results indicate that local sources of PAHs, especially estuary discharges, lead to very different qualities of sediments in coastal zones, where traffic and industrial activities take place.     

Polychlorinated naphthalenes in urban soils: analysis,concentrations, and relation to other persistent organic pollutants

We determined the concentrations of 35 PCNs, 12 PCBs, and 20 PAHs in 49 urban topsoils under different land use (house garden, roadside grassland, alluvial grassland, park areas, industrial sites, agricultural sites) and in nine rural topsoils. The sums of concentrations of 35 PCNs (sigma35 PCNs) were <0.1-15.4 microg kg(-1) in urban soils and <0.1 to 0.82 microg kg(-1) in rural soils. The PCN, PCB, and PAH concentrations were highest at industrial sites and in house gardens. While rural soils receive PCNs, PCBs, and PAHs by common atmospheric deposition, there are site-specific sources of PCNs, PCBs, and PAHs for urban soils such as deposition of contaminated technogenic materials. The PCN, PCB, and PAH concentrations decreased from the central urban to the rural area. In the same order the contribution of lower chlorinated PCNs and PCBs increased because they are more volatile and subject to increased atmospheric transport. The PCNs 52+60, and 73 were more abundant in soil samples than in Halowax mixtures, indicating that combustion contributed to the PCN contamination of the soils.     

A spatial temporal assessment of pollution from PCBs in China

This research represents an assessment of the current state of pollution from polychlorinated biphenyls (PCBs) in China. Various environmental media including sediment, water, organism and soil were analyzed and the spatial character of PCB pollution in each environmental medium was determined. On a national basis, PCB levels in all environmental media were relatively low, with little evidence of major contamination in China's main regions and rivers. However, there were some locations with high PCB concentrations. Sediments in Pearl River (83.1 ng/g) and its estuary (58.9 ng/g), Dalian Bay (58.1 ng/g) and Songhua River (36.8 ng/g) had relatively high level of PCBs. There were also some areas, which were mainly the industrial pollution sites or PCB equipment storage locations, remained seriously polluted with the highest PCB residue level of 150,000 ng/g. In addition, Minjiang Estuary (985.2 ng/g) and Taihu Lake (631 ng/g) had high levels of water pollution, while Pearl Estuary (635.7 ng/g) and Jiaozhou Bay (273.3 ng/g) had relatively high PCB levels in organisms. PCB pollution in soil was limited to a few special pollution areas with the highest PCB level of 4.5448 x 10(6) ng/g. Point source pollution was the common pattern of contamination, influenced primarily by local geographic, economic and historical factors. Analysis of PCB concentrations from the 1980s to 1990s shows an increasing trend, possibly due to the improper disposal of and leakage from PCB containers, chemical transfers, and the general rise of industrial pollution.