Persistent organochlorines in beluga whales (Delphinapterus leucas) from the St Lawrence River estuary--I. Concentrations and patterns of specific PCBs, chlorinated pesticides and polychlorinated dibenzo-p-dioxins and dibenzofurans

Blubber samples from beluga whales (Delphinapterus leucas) in the St Lawrence River estuary were analysed for PCB congeners (ortho- and non-ortho-substituted) and other persistent organochlorines as well as chlorinated dibenzo-dioxins/furans (PCDD/Fs). Major individual components (mean concentrations > 1 microg g(-1)) were 4,4'-DDE, -DDD and -DDT, T12 (a toxaphene-related compound), trans-nonachlor, oxychlordane, mirex, HCB, tris(p-chlorophenyl) methane and dieldrin. Concentrations of SigmaPCBs (8.3-412 microg g(-1)), SigmaDDT (3.36-389 microg g(-1)) and mirex (0.18-6.8 microg g(-1)) were particularly elevated relative to other odontocetes in Canadian waters. SigmaDDT, PCBs (as Aroclor), mirex and T12 concentrations were positively correlated with age of adult females (> 10 years) but only weakly, or not significantly, correlated with age of adult males. PCDD/Fs were present at low ng kg(-1) levels and consisted mainly of penta- and hexachlorofurans, and hepta- and octachlorodioxin. CB126 (3,3',4,4',5-PCB) was the most prominent non-ortho-substituted PCB congener in beluga blubber. Total TCDD toxic equivalents averaged 330 ng kg(-1) in females and 1400 ng kg(-1) in males and were dominated by CB126, and the mono-ortho-substituted congeners CB105 and CB118. Biomagnification factors (BMFs) for mirex and SigmaPCB from fish to beluga ranged from 11 to 16, and were similar to BMFs in Arctic animals, indicating that elevated levels in St Lawrence animals are a consequence of relatively high levels of recalcitrant organochlorines in prey of the beluga in the St Lawrence river system.     

Extractable organohalogens in tissues of beluga whales from the Canadian Arctic and the St. Lawrence estuary

Samples of blubber, brain, kidney, liver, and muscle of individual beluga whales were extracted and analyzed for extractable organic Cl (EOCl), Br (EOBr), and I (EOI) by neutron activation analysis. The highest levels of EOCl (554 microg g(-1) lipid) were found in the kidney of Arctic beluga and the lowest (24 microg g(-1) lipid) in the blubber. Levels in brain and liver lipids were on average of equal magnitude. The unequal distribution of EOCl in tissue lipids is in marked contrast to the equal distribution, in lipid, demonstrated for organochlorines such as DDTs and PCBs by a number of investigations. The distribution of brominated (EOBr) and iodinated (EOI) compounds was similar and markedly different from that of EOCl. The tissue distribution of EOCl seems to be related to the proportion to polar lipids in the tissues. Beluga from St. Lawrence had significantly higher brain EOCl levels than the Arctic samples whereas the levels of EOCl in liver and kidney were higher in the Arctic whales.     

Temporal and biogeographic comparisons of PCBs and persistent organochlorine pollutants in the blubber of fin whales from eastern Canada in 1971-1991

Concentrations of PCB congeners and organochlorine (OC) pesticides were studied in archived fin whale (Balaenoptera physalus) blubber samples collected in 1971-1972 from Newfoundland (Nfld) and Nova Scotia (NS) with the objective of obtaining a historical perspective on contaminant levels and proportions at a time when many persistent OCs were still in use. Concentrations of sigmaPCBs and sigmaDDTs in the blubber of 17 fin whales from historical whaling stations in 1971-1972 were generally in agreement with previously reported values for fin whales from Atlantic Canada. Although some differences in sex and body length (age) distribution of samples occurred, significant differences were detected in the concentrations and patterns of PCBs, DDTs and chlordanes in whales from Nfld and NS, supporting ecological evidence that whales from these regions represent relatively separate stocks. Temporal and geographical variations were examined by comparing data to those reported for fin whales from the St Lawrence Estuary (StL) in 1991 by Gauthier et al. (1997a). Significantly higher levels of sigmaDDT, sigmaCHL and HCB were found in the NS (1971-1972) stock compared with the StL (1991) animals, and in HCB between the Nfld stock (1971-1972) and the StL (1991) animals, as well as higher p,p'-DDE/sigmaDDT and lower p,p'-DDT/sigmaDDT ratios in the 1991 whales suggesting that temporal trends in these whales between the 1970s and 1990s were consistent with those in other marine mammals in Atlantic Canada. Evidence also suggests that geographical variations in patterns may occur for individuals from two relatively distinct stocks of fin whales in Atlantic Canada (NS, Nfld) and perhaps for one population (StL) related to, but recognisably different from the NS stock.     

PCBs and organochlorine pesticides (OCPs) in edible fish and shellfish from China

A wide variety of fish and shellfish were collected from local supermarkets of Dalian, Tianjin and Shanghai in China and analyzed for the concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) such as hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), chlordane compounds (CHLs, including trans-chlordane, cis-chlordane, trans-nonachlor and cis-nonachlor) and dichlorodiphenyltrichloroethane (DDT) and its metabolites (DDTs, including o,p'-DDE, p,p'-DDE, o,p'-DDD, p,p'-DDD, o,p'-DDT and p,p'-DDT). Concentrations of PCBs in samples collected from Dalian, Tianjin and Shanghai ranged from 1.11 to 8.04 ng/g, 1.26 to 5.60 ng/g and 0.83 to 11.4 ng/g on wet weight basis, respectively. The concentrations were lower compared to those in developed countries such as Japan and Italy. Average concentrations of HCB, HCHs, CHLs and DDTs were 0.38, 0.92, 0.47 and 28.9 ng/g on wet weight basis, respectively. The daily intake of PCBs and organochlorine pesticides ingested by people living in these cities in China through fish and shellfish was estimated and compared with those observed in other areas.     

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.     

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.     

Sources and fate of butyltins in the St. Lawrence Estuary ecosystem

Butyltins (BTs) were determined in sediment, zooplankton, benthic fish and invertebrates in the St. Lawrence Estuary and its mixing zone with the Gulf of St. Lawrence (Canada) in an attempt to assess sources and fate of these compounds in a large ecosystem before the enforcement of the world-wide ban of TBT-based antifouling paints. All BTs (MBT, DBT and TBT) were found along the studied area (450 km) where the traffic of large vessels occurs around the year. Concentrations of total butyltins (BTs) in surface sediment were below 6 ng Sn g(-1) d.w. Total BTs concentrations found in zooplankton samples at the mouth of the Saguenay Fjord were the highest (793 ng Sn g(-1) d.w.), indicating the influence of the Fjord on the St. Lawrence contamination. Although a relatively low contamination level was measured in sediment, total BTs concentrations ranged from 9 to 489 ng Sn g(-1) d.w. for benthic organisms. Biota-sediment accumulation factors (BSAFs), calculated on the basis of the organic carbon content in the sediment (concentrations normalized to 1% Corg), ranged from 0.9 to 98.3, and are an indicator of an important source of BTs from the Saguenay Fjord particulate matter. This may be explained by the fact that when TBT is released in a large and deep well stratified coastal environment, it could bind to the suspended particulate matter and then be taken in charge by water column organisms and may be mostly metabolised before it reaches bottom sediment. Sediment is not considered as the main contributor to the contamination of fish and invertebrates. It is expected that any reduction of direct inputs of TBT from ship hulls in a near future should result in a rapid reduction of butyltins in the St. Lawrence ecosystem.     

Organochlorine levels in subcutaneous blubber biopsies of fin whales (Balaenoptera physalus) and striped dolphins (Stenella coeruleoalba) from the Mediterranean Sea

Polychlorinated biphenyls (PCBs) and DDT compounds were determined in subcutaneous blubber of fin whales (Balaenoptera physalus) and striped dolphins (Stenella coeruleoalba) from the Mediterranean Sea. From 1990 to 1993, 68 fin whale and 89 dolphin blubber biopsies were analysed. The whales were sampled while passing through the Ligurian Sea, whereas the dolphins were collected in different areas of the Mediterranean: the Ligurian, Tyrrhenian and Ionian Seas. Total PCBs and DDTs were 5.5-7.1 ppm and 4.2-9.5 ppm, respectively, in the whales and 15.5-86.0 ppm and 15.6-63.5 ppm, respectively, in the dolphins. Thirty PCB congeners were identified for each sample, IUPAC numbers 153, 138, 187, 180 and 170 being the most abundant, totalling an average of 55% of total PCBs in the whale and 60% in the dolphin. The large differences in accumulation are related to position in the food chain. In striped dolphins significant differences were found in relation to sampling site, and in fin whales in relation to sex.     

Thirty year monitoring of PCBs, organochlorine pesticides and tetrabromodiphenylether in eel from The Netherlands

Because of their excellent properties as a biomonitor, yellow eels (Anguilla anguilla) have been used for time-trend monitoring of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and tetrabrominated diphenylether (tetra-BDE). The program has now lasted for thirty years and has delivered valuable information on trends and spatial differences of these compounds in the delta of the rivers Rhine and Meuse and other Dutch canals, rivers and lakes. Specific local PCB, HCH and dieldrin contaminations were identified. Temporal trends show a slow decrease of PCB concentrations since 1977. Eels from the rivers Rhine and Meuse still exceed present European maximum residue limits for dioxin-like PCBs. Apart from some exceptions, OCP and tetra-BDE concentrations have also decreased, and more than those of PCBs. Fat contents of eel have decreased from an average of 21 to ca. 13%. This decrease in fat contents, coincides with the strong reduction of the European eel stock.     

Distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in human serum from urban areas in Korea

Concentrations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were determined in serum samples from residents of a Korean urban area (Seoul). This study was performed on 40 Koreans in the general population, aged 27-58, who had resided in urban areas for more than 10 years without occupational exposure to organochlorine pollutants. To our knowledge, this study was the first report on serum concentrations of OCPs in Korean residents. p,p'-DDE, beta-HCH, p,p'-DDT, HCB, and trans-nonachlor were the dominant OCPs in most samples. In addition, concentrations of 22 OCPs were measured by the isotope dilution method with GC-HRMS, which gave accurate and precise data for investigations of trend and international comparisons. The dominant PCBs were PCB153, 138, 180, 187, and PCB118, which contributed 60% to total PCBs. The median concentrations of total OCPs and total PCBs were 315 ng g(-1) lipid and 104 ng g(-1) lipid, respectively. In females, the serum concentrations of all determined organochlorine compounds except beta-HCH were positively correlated with age, and higher concentrations of organochlorine pollutants were found in males than in females. Compared to our previous studies, PCB concentrations in serum from urban areas have substantially decreased during the last decade leading to the observation that the strict regulation of PCBs was helpful in controlling the concentration of PCBs in the environment. Extensive monitoring programs are required for evaluating the concentrations of OCPs and PCBs in serum samples of the general population as an indicator of possible adverse health effects.     

A multibiomarker approach on the Atlantic tomcod (Microgadus tomcod) in the St. Lawrence Estuary

A multibiomarker approach was developed on juvenile Atlantic tomcod (Microgadus tomcod) to evaluate the pertinence of this approach for low-cost screening assessment of the environmental quality of various coastal sites within estuaries. Several biometric indices and biomarkers (ethoxyresorufin-O-deethylase (EROD) activity, metallothionein concentration, and immune responses) were investigated on immature and maturing tomcods (≤31 months) collected in four environmentally contrasted sites in the St. Lawrence Estuary (SLE). Simultaneous examination of various age classes provides the opportunity to detect short-term responses in sensitive young-of-the-year fish (e.g., EROD induction) and longer-time effects associated with chronic exposure and bioaccumulation (e.g., metallothionein induction). Principal component analysis was helpful to discriminate between responses possibly related to contaminant exposure (EROD, metallothionein) and responses that could be affected by upstream–downstream gradient (immune response, biometric indices). Measurement of a battery of biomarkers in young tomcods at several sites along the shore of the SLE is a low-cost screening investigation useful to identify hot spots requiring further investigation with chemical analysis and additional reference sites.     

Concentrations and characteristics of organochlorine pesticides in aquatic biota from Qiantang River in China

The Qiantang River is a typical river flowing through an agricultural area in China. It was studied in 2006 for its aquatic biota quality by determining 13 organochlorine pesticides (OCPs) in the edible parts of crabs, clams, shrimp, fish, aquatic plants, as well as water and sediments collected from seven sites along its upper reaches all the way downstream. The levels of all insecticides were in the range of 17+/-13 (water plants), 35+/-36 (shrimp), 32+/-14 (crabs), 39+/-21 (clams), 47+/-35 (fish) ng/g wet weight (ww) and in the range of 2936+/-2356 (water plants), 5827+/-6013 (shrimp), 2102+/-966 (crabs), 1859+/-1018 (clams), 3624+/-11331 (fish) ng/g lipid. DDT and its metabolites were the predominant contaminants in most biota. A linear relationship was observed between the log bio-concentration factor (BCF) and log octanol-water partition coefficients (Kow) for fish, clams and shrimp. Composition analyses in various environmental media indicated a recent usage of lindane and dicofol into the river.     

Study on PCBs,PCDD/Fs,organochlorine pesticides,heavy metals and arsenic content in freshwater fish species from the River Turia (Spain)

In this study samples of common trout, European eel and barbel have been analysed for the levels of heavy metals such as lead (Pb), cadmium (Cd), zinc (Zn), copper (Cu), and the metalloid arsenic (As). Polychlorinated biphenyls (PCBs), including three non-ortho substituted PCBs, 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and DDT and its two main metabolites were also analysed in some selected samples, in order to evaluate the extent of contamination of the River Turia basin. All samples presented detectable levels of the elements analysed, presenting zinc the highest concentrations. European eel was the species found to highly accumulate these contaminants. Regarding organochlorinated compounds, seven samples exhibited detectable levels of the most toxic PCDD/Fs congener, the 2,3,7,8-TCDD. Non-ortho PCBs were not detected or not quantified in almost all samples and the sum of the individual PCB congeners determined were low compared to other aquatic ecosystems with similar fish species.     

Tris (4-chlorophenyl) methane and tris (4-chlorophenyl) methanol in marine mammals from the Estuary and Gulf of St. Lawrence

Levels of tris (4-chlorophenyl) methanol (TCPM) and its presumed precursor tris (4-chlorophenyl) methane (TCPMe) are reported in marine mammals from the Estuary and Gulf of St. Lawrence, Canada. These compounds were measured in blubber samples of seals and whales using ion trap mass spectrometry (MS/MS) detection. Detectable concentrations of both TCPM and TCPMe were observed in all of the samples analysed. Concentrations of these compounds varied with species ranging from 1.7 to 153 and from 1.3 to 50.6 ng/g lipid wt. for TCPM and TCPMe, respectively. TCPM was from 1.3 to 10 times more concentrated than TCPMe. The highest levels of both TCPM and TCPMe were observed in adult male beluga whales (Delphinapterus leucas) from the St. Lawrence Estuary, while adult female beluga whales from the same area showed levels similar to those in the seals examined. Among the four seal species investigated, TCPM and TCPMe levels were the highest in grey (Halichoerus grypus) and hooded (Cystophora cristata) seals, and lowest in harp seals (Phoca groenlandica). Intermediate levels were found in harbour seals (Phoca vitulina); however, their concentrations might be underestimated considering the younger mean age of these animals. Ratios of both 4,4'-DDE/sigma DDT and TCPM/sigma TCP were very similar between animals from the same species. Strong correlations between sigma TCP and sigma DDT were also observed for each species of mammals, most likely indicating that both sigma TCP and sigma DDT are bioaccumulated in marine mammals. The relationships between sigma DDT and sigma TCP also demonstrate that sigma TCP are less bioaccumulated than sigma DDT by the marine mammal species examined.     

The levels and distribution of organochlorine pesticides (OCPs) in sediments from the Haihe River, China

The levels and distribution patterns of the selected organochlorine pesticides (OCPs=p,p'-DDT, o,p'-DDT, p,p'-DDE, p,p'-DDD, alpha-, beta-, gamma- and delta-HCH) in surficial sediments from the Haihe River and Dagu Drainage River of Tianjin were investigated by means of gas chromatography coupled with micro-electronic capture detector (GC-microECD). Concentrations of OCPs in the sediments from the Haihe River ranged from 1.88 to 18.76ng g(-1) (mean 7.33ng g(-1)) for sum HCH, 0.32-80.18ng g(-1) (mean 15.94ng g(-1)) for sum DDT. Compared with the Haihe River, the Dagu Drainage River was much more contaminated by HCHs and DDTs, wherein sum HCH ranged from 33.24 to 141.03ng g(-1) (mean 87.74ng g(-1)) and sum DDT ranged from 3.60 to 83.49ng g(-1) with a mean value of 35.52ng g(-1). The concentration distribution of sum DDT and sum HCH was different indicated their different contamination sources. Composition analyses indicated that a recent usage or discharge of HCH and DDT into the Dagu Drainage River.     

Distribution and ecological risk of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in surface sediments from the Bizerte lagoon,Tunisia

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in 18 surface sediment samples collected from Bizerte lagoon, Tunisia. The total concentrations of ten PCBs (∑PCBs) and of four OCPs (∑OCPs) in the sediments from this area ranged from 0.8 to 14.6 ng g^?1 dw (average value, 3.9 ng g^?1 dw) and from 1.1 to 14.0 ng g^?1 dw (average value, 3.3 ng g^?1 dw), respectively. Among the OCPs, the range of concentrations of dichlorodiphenyltrichloroethane and its metabolites (DDTs) and hexachlorobenzene (HCB) were 0.3–11.5 ng g^?1 dw (1.9 ng g^?1 dw) and 0.6–2.5 ng g^?1 dw (1.4 ng g^?1 dw), respectively. Compositional analyses of the POPs indicated that PCB 153, 138 and 180 were the predominant congeners accounting for 60 % of the total PCBs. In addition, p,p′-DDT was found to be the dominant DDTs, demonstrating recent inputs in the environment. Compared with some other regions of the world, the Bizerte lagoon exhibited low levels of PCBs and moderate levels of HCB and DDTs. The high ratios ΣPCBs/ΣDDTs indicated predominant industrial versus agricultural activities in this area. According to the established guidelines for sediment quality, the risk of adverse biological effects from such levels of OCPs and PCBs, as recorded at most of the study sites, was insignificant. However, the higher concentrations in stations S1 and S3 could cause biological damage.     

Integrated spatial health assessment of yellow perch (Perca flavescens) populations from the St. Lawrence River (QC,Canada), part B: cellular and transcriptomic effects

Environmental Science and Pollution Research - Multi-biological level assessments have become great tools to evaluate the health of aquatic ecosystems. Using this approach, a complementary study...     

Wintertime size distribution of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in the urban environment: Street- vs rooftop-level measurements

The size distribution of ambient air particles and associated organic pollutants, such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) including hexachlorocyclohexanes (HCHs), DDT and metabolites, etc., was investigated at a traffic-impacted site of Thessaloniki, Greece. Investigation took place during wintertime of 2006 at two heights above ground: at the street level (1.5 m) and at the rooftop level (15 m). Size-resolved samples (<0.95 μm, 0.95–1.5 μm, 1.5–3 μm, 3–7.5 μm and >7.5 μm) were concurrently collected from the two height levels using five-stage high volume cascade impactors. At both heights, particle mass exhibited bimodal distribution with peaks in the 0.95–1.5 μm and the 3–7.5 μm size fractions, whereas most organic pollutants exhibited one peak at 0.95–1.5 μm. Apart from the 0.95–1.5 μm fraction, particle concentrations of all size ranges were significantly higher at the street level than at the rooftop as a result of more intensive vehicular emissions and road dust resuspension. On the contrary, the concentrations of most organic pollutants did not differentiate significantly between the two elevations.     

Occurrence of alkylphenol polyethoxylates in the St. Lawrence River and their bioconcentration by mussels (Elliptio complanata)

A study was conducted in 1999 to determine the occurrence of alkylphenol polyethoxylates in the St. Lawrence River and their bioconcentration by mussels (Elliptio complanata). Concentrations of selected contaminants were measured in surface water, municipal effluent, sediments and mussels. Analyses were performed on 4-tert-octylphenol (4-t-OP), 4-n-nonylphenol (4-n-NP), nonylphenol polyethoxylates (NP(1-16)EO), nonylphenol-mono and di-ethoxycarboxylic acids (NP(1)EC and NP(2)EC), and octylphenol-mono and di-ethoxycarboxylic acids (OP(1)EC and OP(2)EC). Mussels (Elliptio complanata) taken from a reference lake were placed in cages and submerged for 62 days at two sites in the St. Lawrence River, 1.5 km upstream and 5 km downstream of the outfall of a municipal wastewater treatment plant. The results showed that many of the target chemicals were present in all matrices studied: in water, at ppt and ppb levels, and reaching ppm levels in sediments and mussels. Concentrations of these contaminants were higher in matrices sampled at the downstream site than in those drawn at the site upstream of the Montreal effluent outfall, especially in sediments. Likewise, the slight, but not significant, bioconcentration of certain alkylphenol polyethoxylates (AP(n)EO) in the mussels was more noticeable at the downstream site than at the upstream site.     

Biomonitoring of persistent organochlorine pesticides, PCDD/PCDFs and dioxin-like PCBs in blood of children from South West Germany (Baden-Wuerttemberg) from 1993 to 2003

In the context of a monitoring program, persistent organic pollutants (POPs) were quantified in the blood of 10 year old children at four different demographic regions in Baden-Wuerttemberg, a highly industrialised federal state in South West Germany. DDE, HCB, PCB 138, PCB 153 and PCB 180 were measured in 1996/1997, 1998/1999, 2000/2001 and 2002/2003 in individual samples of about 400 children per year. PCDD/PCDFs and some relevant coplanar PCBs were determined in pooled samples from children in seven cycles from 1993 to 2003. Blood concentrations of the investigated compounds decreased in that time period by a factor of 2-4 with the exception of most PCDFs. The concentrations of POPs in the blood of the children were distinctly lower than the concentrations reported for adults. Breast feeding was associated with about 30% higher median concentrations of DDE, HCB, PCBs and a 30% increase for mean PCDD/PCDF concentrations. Concerning demographic differences, significant lower concentrations of HCB, PCBs and PCDD/PCDFs could be seen in children from Mannheim compared to the region of Aulendorf. About 10-20% higher concentrations were found in boys compared to girls for HCB, indicator PCBs and PCDD/PCDFs. The pattern of non-ortho and mono-ortho PCBs in the blood of children was similar to the pattern reported for mother's milk, and PCB 126 and PCB 156 contributed about 70% to the toxicity of dioxin-like PCBs and about one-third to total TEQ including PCDD/PCDFs.