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1.
Zhao H  Guo R  Chen J  Liang X 《Chemosphere》2006,64(4):574-578
By a soil column liquid chromatograph (SCLC) method, the soil organic carbon content normalized adsorption coefficients (K(oc)) of six polybrominated biphenyls (PBB15, PBB26, PBB31, PBB49, PBB103 and PBB153) are determined. Based on the similarity between the molecular structures of PBBs and PCBs, a simple linear predictive model has been developed with the correlation coefficient R=0.9812 and standard error SE=0.19. The logK(oc) values of any PBB congeners can be predicted by using the logK(oc) values of the corresponding PCBs according to this model. Using the published data for logK(oc) values of PCB congeners, logK(oc) values of all 209 PBB congeners have been for the first time predicted. Compared with the data obtained from the experiment, the results of prediction are very accurate.  相似文献   

2.
We studied pregnancy-related changes in serum concentrations of five polychlorinated biphenyls (PCBs, CB 118, CB 138, CB 153, CB 156, CB 180), three hydroxylated PCB metabolites (4-OH-CB107, 4-OH-CB146, 4-OH-CB187), and pentachlorophenol (PCP). Median serum lipid content increased 2-fold between early (weeks 9-13) and late pregnancy (weeks 35-36) (N = 10), whereas median PCB levels in serum lipids decreased 20-46%, suggesting a dilution of PCB concentrations in serum lipids. Nevertheless, strong positive intra-individual correlations (Spearman’s r = 0.61-0.99) were seen for PCBs during the whole study period. Thus, if samples have been collected within the same relative narrow time window during pregnancy, PCB results from one single sampling occasion can be used in assessment of relative differences in body burdens during the whole pregnancy period. Concentrations of OH-PCBs in blood serum tended to decline as pregnancy progressed, although among some women the concentrations increased at the end of pregnancy. Positive intra-individual correlations (r = 0.66-0.99) between OH-PCB concentrations were observed during the first and second trimester, whereas correlations with third trimester concentrations were more diverging (r = −0.70-0.85). No decline in PCP concentrations was observed during pregnancy and no significant correlations were found between concentrations at different sampling periods. Our results suggest that for both OH-PCBs and PCP, sampling has to be more specifically timed depending on the time period during pregnancy that is of interest. The differences in patterns of intra- and inter-individual variability of the studied compounds may be due to a combination of factors, including lipid solubility, persistence of the compounds, distribution in blood, metabolic formation, and pregnancy-related changes in body composition and physiological processes.  相似文献   

3.
Nault R  Al-Hameedi S  Moon TW 《Chemosphere》2012,87(9):1057-1062
The production of polychlorinated biphenyls (PCBs) was banned in 1977 but these chemicals persist in the environment and threaten aquatic organisms. PCB exposure often results in activation of the aryl hydrocarbon receptor (AhR) and increases in hepatic detoxification mechanisms. Activation of these detoxification mechanisms is believed to be associated with energetic demands that may come at the expense of other physiological processes such as growth, activity and reproduction. We tested the hypothesis that exposure to sub-lethal levels of PCBs results in increased energy demand and energy mobilization using both an in vivo and in vitro approach. Rainbow trout (Oncorhynchus mykiss) received a single intraperitoneal sub-lethal dose (50 μg kg−1) of 3,3’,4,4’,5-pentachlorobiphenyl (PCB 126) and left for 10 d after which standard oxygen consumption and plasma and liver metabolites were assessed. PCB 126 exposed trout did not alter standard oxygen consumption but did increase plasma glucose concentration implying the mobilization of glucose to cope with this exposure regime. Cellular respiration was assessed in trout hepatocytes exposed to PCB 126 or PCB 77 (3,3′4,4′-tetrachlorobiphenyl) two AhR activators but with different potencies (PCB 126 ? PCB 77). Mitochondrial respiration was assessed by stimulating complex II with succinate and although no increases in respiration were associated with PCB exposure in non-stimulated cells, PCB 77 impaired mitochondrial respiration by preventing stimulation of complex II respiration and potentially masking any actual energetic costs of PCB exposure. These studies suggest that energy is mobilized upon exposure to PCBs, however, actual increases in energy demand may be overshadowed by impaired mitochondrial respiration.  相似文献   

4.
Yang H  Xue B  Jin L  Zhou S  Liu W 《Chemosphere》2011,83(2):137-143
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.  相似文献   

5.
Research on the environmental fate and transport of PCBs in Lake Ontario basin depends, among other aspects, on the availability of representative data sets for upstream sources, but data are lacking for most US Lake Ontario tributaries. In this study, water samples were collected between September 2004 and October 2008 from five tributaries and were analyzed for 209 polychlorinated biphenyls (PCB) with high-resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) following EPA Method 1668A. Total PCB concentrations ranged between 0.31 and 42.75 ng L−1. Congeners between Di and Hexa PCBs accounted between 70 and 99% of the total PCB. The tributary with highest PCB concentrations presented similar pattern and percentage levels to Aroclor 1242. Total average loads for the sampling events ranged between 1.85 g d−1 and 59.08 g d−1. PCB concentrations were evaluated against other variables and other studies (including different matrices) to better understand their transport. The methodology used is reliable to assess PCB contamination in surface water.  相似文献   

6.
Individual eggs of six species of birds from Norway representing different food chains were analysed for residues of polybrominated biphenyls (PBBs). In all species, the residue pattern was dominated by hexaBBs. The dominating congeners were PBB 153, PBB 154, and PBB 155. Whereas PBB 153 is present in technical hexabromobiphenyl, PBB 154 and PBB 155 are formed by the reductive debromination of decabromobiphenyl. This was evidenced by the detection of several heptaBBs and octaBBs all of which are typical degradation intermediates of PBB 209. Hepta- and octaBBs were more than one order of magnitude less abundant than the hexaBBs. The second most prevailing homologue group was pentaBBs. The most relevant pentabrominated isomers were PBB 99 and PBB 101. Concentrations of the three hexaBBs - PBB 153, PBB 154, and PBB 155 - amounted to 1.3-13 ng/g wet weight or 3-23% of the contamination with polybrominated diphenyl ethers.  相似文献   

7.
Human exposure to PCBs is nearly universal in North America. While most exposure can be linked to consumption of contaminated fish, detection of PCBs in non-fish eating populations suggests that other routes of exposure including inhalation of PCB-laden particles or volatile congeners, ingestion of contaminated soil or dust, or dermal absorption following direct contact are also important. In an effort to assess the role of the residential environment as a source of exposure, vacuum dust was collected from the homes of 26 Wisconsin residents whose serum PCB levels had been measured approximately 2 years earlier. More than 60 congeners were detected in dust with all of the samples containing congeners 101, 110, 138 and 153. Total PCB levels ranged from 8.8 to 1186 ng g−1 with levels being highest in vacuum dust from homes built between 1959 and 1970. Total PCB levels ranged from 0.05 to 8.34 μg L−1 in serum collected from the adults living in these households, with congeners 138, 153 and 180 predominating. Hexa- and hepta-chlorinated biphenyls comprised 73% of the total residues detected in serum. However, most of the residues found in dust were lower chlorinated congeners with tetra- and penta-chlorinated biphenyls being dominant. Following log transformation, a positive association was found between serum and house dust PCB levels. This association was stronger among infrequent consumers of Great Lake fish, but of borderline statistical significance. This exploratory study suggests that house dust may be a significant source of exposure to PCBs and supports the need for further investigations.  相似文献   

8.

Background

Polychlorinated biphenyls (PCBs) and organochlorine pesticides are common environmental contaminants that have been associated with human health problems.

Objectives

To assess serum concentrations of several organochlorine contaminants in general population living in a city with an ancient agricultural tradition and to identify possible exposure sources in Sicily.

Methods

A cross-sectional study was conducted on 101 individuals. Each participant answered a face-to-face questionnaire submitted by well-trained personnel and provided a serum sample which was analyzed for the concentrations of PCBs, HCB, HCHs and DDTs by using gas-chromatography coupled with mass spectrometry.

Results

HCB, p,p′-DDE, PCB 138, PCB 153 and PCB 180 were detected in more than 80% of the study participants. The ng g−1 lipid median concentrations were: 18.6 for HCB; 175.1 for p,p′-DDE; 22. for PCB 138; 32.5 for PCB 153 and 23.0 for PCB 180. PCB 153 and PCB 138, PCB 138 and PCB 180, PCB 153 and PCB 180, and p,p′-DDE and HCB showed a high correlation each other (p < 0.05). HCB and p,p′-DDE concentrations were significantly higher in subjects >49 years old (adj-p = 0.03 in 50-69 years old and adj-p < 0.001 in >69 years old, respectively) whereas PCB 138, PCB 153 and PCB 180 concentrations were higher in males (adj-p = 0.03), in subjects >69 years old (adj-p = 0.04) and in current smokers (adj-p = 0.04).

Conclusions

The present study shows that serum concentrations of organochlorine compounds detected in subjects living in a small Sicilian city with ancient agricultural tradition are similar to those found in subjects living in urban areas of other countries. However, further investigations are needed to compare data from rural/urban areas in the same country, assessing correlations between serum concentrations of several chemical compounds and potential health effects in general population.  相似文献   

9.
The Subantarctic Kerguelen Islands (49°S, 70°E) contain freshwater ecosystems among the most isolated in the world. Concentrations of polychlorinated biphenyls (PCBs) were assessed in the muscle of 48 brook trout and 38 brown trout caught during summer and spring 2006 in the rivers, lakes and ponds of Kerguelen. The sum of 29 PCBs averaged 404 and 358 ng g−1 lipid, and dioxin-like PCB was 19 and 69 ng g−1 lipid, in brook and brown trout, respectively. The values showed a high variability and some fish accumulated PCBs at levels similar to those of fish from impacted areas. While inter-sex differences were limited, the season and the morphotype appeared to have the most influence. Fish captured in summer had muscle PCB concentrations about three times higher than those caught in spring and the ‘river’ morphotype of brook trout showed the highest PCB levels.  相似文献   

10.
Twenty-four congeners of polychlorinated biphenyls (PCBs) were measured in 83 air samples and 20 elastic sealants samples of apartments with PCB-containing sealants. In addition, PCBs were measured in 21 air samples from reference apartments located in an uncontaminated section of the same estate. The PCBtot levels in the air of the contaminated section were 168-3843 ng m−3 (mean: 1030 ng m−3), while the mean levels in the reference apartments were 6.03 ng m−3. The sum of the 24 measured PCB congeners in sealants from the contaminated section was 187-221 680 mg kg−1. Principal component analysis revealed four groups among the sealant samples with different congener compositions, only two of which were clearly similar to known PCB mixtures, while two were not. Significant correlations and intercorrelations were observed between the lower chlorinated congeners in air and sealant, e.g. for PCB 28air and 28seal (p = 0.04) and for PCB 28air and 52air, 52seal. However, no correlation was observed between the lower chlorinated congeners and the sums of PCB (∑PCB6 or ∑PCB24) or the higher chlorinated congeners. Analysis of air concentrations in relation to questionnaire data indicated that the indoor air levels could be reduced by increased cleaning and airing frequencies.  相似文献   

11.
Jiang Y  Wang X  Zhu K  Wu M  Sheng G  Fu J 《Chemosphere》2011,83(6):767-773
Surface soil samples taken from 55 sampling sites at the urban areas of Shanghai were collected and analyzed for the occurrence of 144 polychlorinated biphenyls (PCBs) by GC-μECD. The results showed that totally 74 PCB congeners were identified and the mean concentration of total PCBs was 3057 ng kg−1 with a range of 232 to 11325 ng kg−1. Compared with the related reports, the level of PCBs contamination in this study was approximately equal to the global background value in soils, but higher than Chinese background for rural and urban soils. According to the compositional profiles of PCBs homologues, a higher proportion of low chlorinated (from tri-CBs to hexa-CBs) was observed. The results indicated that PCB15 + 13, PCB18, PCB28, PCB104 + 47 and PCB153 were the most dominant congeners among the identified PCBs. Through homologues analysis, cluster analysis and principal component analysis (PCA), it was found that PCBs were stretched from mixed local sources, and appeared to be mostly originated by Aroclor 1260- and 1254-like mixtures as well as some samples influenced by Aroclor 1232 and 1242. The correlation analysis showed the relatively good correlation among the PCB homologues and soil total organic carbon (TOC), suggesting important influence of soil TOC on PCBs contamination in soil matrix in Shanghai region. The toxic equivalency (TEQ) concentrations of these six dioxin-like PCBs detected in urban soil samples range from 2.71 to 24.9 pg kg−1-PCDDeq with a mean 8.18 pg kg−1-PCDDeq.  相似文献   

12.
Cakirogullari GC  Secer S 《Chemosphere》2011,85(11):1713-1718
The concentrations of indicator polychlorinated biphenyls (PCBs) and organochlorine insecticides were determined in bonito (Sardasarda L. 1758) and anchovy (Engraulisencrasicolus L. 1758) from the Black Sea, Turkey. Concentrations of total indicator PCBs ranged between <1-17.0 in bonito, and <1-17.5 ng/g fresh weight in anchovy, and total of 1,1,1-trichloro-2,2-bis-chlorophenyl-ethane and its metabolites’ (DDTs) concentrations ranged between 13.4-26.3, and 2.96-19.0 ng/g fresh weight in bonito and anchovy respectively. PCB 52, p,p′-DDE and endosulfan (α + β) were found dominant in both of the fish species. Except endosulfan, and some DDT metabolites, none of the studied organochlorine pesticides was detected in the fish samples. Concentrations of PCBs in anchovy were found higher than those in bonito, whereas DDT and endosulfan concentrations were found similar in both of the fish species. All of the fish samples had residue concentrations below the maximum residue limits (MRL) recommended by FAO/WHO Codex Alimentarius Commission.  相似文献   

13.
C Xia  JC Lam  X Wu  Z Xie  PK Lam 《Chemosphere》2012,89(8):944-949
Muscle tissues of large yellow croakers (Pseudosciaena crocea) and sliver pomfret (Pampus argenteus) from nine coastal cities of East China including Dalian, Tianjin, Qingdao, Shanghai, Zhoushan, Wenzhou, Fuzhou, Quanzhou and Xiamen were analyzed for polychlorinated biphenyl (PCB) concentrations. Thirty-six PCB congeners were quantified in the fishes, of which 11 congeners were dioxin-like PCBs. The total PCB concentrations of the present study were at the low end of the global range, which may be related to the smaller usage and shorter consumption history of PCBs in China. PCBs 18, 29, 52, 66, 101, 104, 138, 153, 180 and 194 were the major constituents found in the fish samples. Regression analysis showed a strong positive correlation (R2 = 0.800; p < 0.001) between total dioxin-like PCBs and total PCB concentrations, and that total PCB concentrations explain 80% of the variability in total dioxin-like PCB concentrations. Among the species investigated, significantly higher concentrations of total PCBs were found in croakers than in pomfrets, which may be attributed to their different feeding and living habits. No significant difference in total PCB concentrations among the cities was observed; principal component analysis (PCA) of PCB profiles indicated that PCB pollution came from similar sources in the sampling areas and that there may be other PCB sources in Dalian and Wenzhou. The calculated carcinogenic risks (CRs) from the two species based on a low consumption group and high consumption group were all greater than 10−6, suggesting that daily exposure to dioxin-like PCBs via fish consumption results in a lifetime cancer risk of greater than one in one million. In contrast, the hazard quotients (HQs) of noncancer risks were all less than unity.  相似文献   

14.
Widespread use of phenols has led to ubiquitous exposure to phenols. In experimental animals, phenols increased resorptions, reduced live litter size and fetal body weights. However, there are limited epidemiological evidences of the relationships between exposure to phenols and pregnancy outcomes. We evaluated the associations between parental urinary levels of various phenols and spontaneous abortion in a Chinese population residing in the middle and lower reaches of the Yangtze River. A case-control study was conducted that included 70 case couples with medically unexplained spontaneous abortion and 180 control couples who did not have a history of spontaneous abortion and had at least one living child. Both parental urinary phenols were measured by ultra-high performance liquid chromatography-tandem mass spectrometry including bisphenol A (BPA), benzophenone-3 (BP-3), 2,3,4-trichlorophenol (2,3,4-TCP), pentachlorophenol (PCP), 4-n-octylphenol (4-n-OP) and 4-n-nonylphenol (4-n-NP). Compared with the low exposure group, there was an increased risk of spontaneous abortion with high paternal urinary PCP concentration [odds ratio (OR) = 2.09, 95% Confidence Interval (CI), 1.05–4.14], and maternal exposure to 4-n-OP and alkylphenol(s) also significantly increased the risk of spontaneous abortion (OR = 2.21, 95% CI, 1.02–4.80; OR = 2.81, 95% CI, 1.39–5.65, respectively). Our study firstly provides the evidence that paternal PCP exposure, maternal 4-n-OP and alkylphenol(s) exposure are associated with spontaneous abortion in humans.  相似文献   

15.
Breast milk is a noninvasive specimen to assess maternal and infant exposure to polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). In this study, 206 breast milk samples were collected from 87 participants during lactation, at <7, 15, 30, or 90 days postpartum in four cities in Korea. The total concentrations of PCBs (ΣPCB) and OCPs (ΣOCP) ranged from <LOQ to 84.0 (median: 12.1) ng g−1 lipid weight and from <LOQ to 559 (median: 144) ng g−1 lipid weight, respectively. The residue levels of these contaminants measured in our study were relatively lower than those reported for European, African and Asian populations. Within a month postpartum typically after day seven the levels of ΣPCB and ΣOCP significantly increased. Some OCP compounds were correlated with maternal age, BMI, parity, and delivery mode. Certain types of dietary habits such as seafood and noodle consumption were significantly associated with ΣPCB and ΣOCP. The estimated daily intakes (EDIs) of ΣPCB and ΣOCP were 45.2–127 ng kg−1 bw day−1 and 625–1259 ng kg−1 bw day−1 during lactation, respectively, which are lower than the threshold values proposed by the US EPA and Health Canada. The exposure of Korean infants to chlordanes via breast milk had a potential health risk which deserves further investigation.  相似文献   

16.
Fish and seafood are important contributions to a healthy diet, but also contain persistent organic pollutants (POPs) like polybrominated diphenylethers (PBDEs) and polychlorinated biphenyls (PCBs). Discrepancies have been found between intake and accumulated levels of POPs, where fish consumers have had similar levels of POPs to the general population. Similarly fish oil consumption has been found to reduce accumulation of POPs. This study examined the accumulation of BDE47 or PCB153 in mice fed diets with different nutritional composition, using female mice with pre-weanling pups exposed through gestation and lactation. A fish-based diet was compared to a standard casein-based rodent diet. All diets had low background levels of environmental contaminants and were spiked with BDE47 or PCB153 to levels representing a realistic (∼0.004 μmol kgbw−1 d) or a high dietary exposure (∼1.3 μmol kgbw−1 d). Accumulation of BDE47 or PCB153 in offspring tissues after 18 d lactation reflected the maternal exposure levels. However, the pups of dams fed a fish-based diet had consistently lower BDE47 accumulation in liver, fat and stomach than pups from casein-fed dams. Similarly the pups of dams fed a high dose of PCB153 in a fish diet also accumulated less PCB153 than pups of the dams fed a casein diet, although not significant. In conclusion, the fish based diets seemed to reduce transfer of BDE47 and PCB153 from dams to pups. The study highlights that in-depth knowledge about nutritional impact on toxicokinetics is of great interest to vulnerable consumers.  相似文献   

17.
The effect of heavy metals at environmentally relevant concentrations on couple fecundity has received limited study despite ubiquitous exposure. In 2005-2009, couples (n = 501) desiring pregnancy and discontinuing contraception were recruited and asked to complete interviews and to provide blood specimens for the quantification of cadmium (μg L−1), lead (μg dL−1) and mercury (μg L−1) using inductively coupled plasma-mass spectrometry. Couples completed daily journals on lifestyle and intercourse along with menstruation and pregnancy testing for women. Couples were followed for 12 months or until pregnant. Fecundability odds ratios (FORs) and 95% confidence intervals (CIs) were estimated adjusting for age, body mass index, cotinine, and serum lipids in relation to female then male exposures. FORs <1 denote a longer time to pregnancy. In adjusted models, reduced FORs were observed for both female cadmium (0.78; 95% CI 0.63-0.97) and male lead (0.85; 95% CI 0.73-0.98) concentrations. When jointly modeling couples’ exposures, only male lead concentration significantly reduced the FOR (0.82; 95% CI 0.68, 0.97), though the FOR remained <1 for female cadmium (0.80; 95% CI 0.64, 1.00). This prospective couple based cohort with longitudinal capture of time to pregnancy is suggestive of cadmium and lead’s reproductive toxicity at environmentally relevant concentrations.  相似文献   

18.
Thirty persistent organohalogen compounds including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were determined in breast milk samples (n = 36) of primipara and multipara mothers from Bizerte in 2010. The analytical procedure involved the application of liquid-liquid extraction and gas chromatography with electron capture detector (GC-ECD) or mass spectrometry detector (GC-MS) for identification and quantification. Organohalogen compounds were found in all the analyzed samples, with predominance of p,p′-DDE, p,p′-DDT, p,p′-DDD, HCB and PCBs. The mean concentration of ∑DDTs in breast milk was 1163.9 ng g−1 lipid wt. The ratio of p,p′-DDE/p,p′-DDT was low, suggesting that there is fresh intake of commercial DDT products in Bizerte. The mean levels of HCB and PCB were 286.8 and 331.2 ng g−1 lipid wt respectively. These results were compared with the levels obtained in a previous study carried out in the same area in 2003. A general decrease of ∑DDTs levels and an increase of PCB levels were observed. Among the 10 PBDE congeners evaluated, BDE-28, BDE-47, BDE-99, BDE-66, BDE-138, BDE-100, BDE-154, BDE-153, and BDE-183 were detected in the analyzed samples at different frequency. The total PBDE concentrations ranged from 2.5 to 22.6 ng g−1 lipid wt in the samples, with a mean and median value of 10.7 and 9.8 ng g−1 lipid wt respectively. To our knowledge, this is the first data of PBDEs in Tunisian human milk. The present study shows that age and parity are factors influencing the levels of some organohalogen compounds in human milk.  相似文献   

19.
Fu J  Wang Y  Zhang A  Zhang Q  Zhao Z  Wang T  Jiang G 《Chemosphere》2011,82(5):648-655
Fengjiang is a large e-waste dismantling site located in southeast China. In this paper, apple snail and soil samples were collected from this e-waste dismantling site and 25 vicinal towns to investigate the contamination status, spatial distributions and congener patterns of polychlorinated biphenyls (PCBs) and polybrominated biphenyl ethers (PBDEs). Total PCB concentrations in apple snails (3.78-1812 ng g−1 dry weight (dw)) were significant higher than that in soil samples (0.48-90.1 ng g−1 dw). PBDE (excluding BDE 209) concentrations in apple snail and soil samples ranged from 0.09 to 27.7 ng g−1 dw and 0.06 to 31.2 ng g−1 dw, respectively. Concentrations of PCBs and PBDEs in snails and soils correlated negatively with the distance from Fengjiang. Both the concentrations and profiles of the pollutants were significantly correlated (p < 0.05) between the snail and soil samples, indicating the suitability of apple snail as a reliable bioindicator for PCBs and PBDEs contamination in this region. Relatively high concentrations of PCBs and PBDEs at locations far from e-waste dismantling sites implied that these pollutants have been transported to surrounding regions.  相似文献   

20.
The main objective of this work was to assess the atmospheric concentrations and seasonal variations of selected POPs in a sub-alpine location where few data are available. A monitoring and research station was set up at the JRC Ispra EMEP site (Italy). We present and discuss a one-year data set (2005-2006) on PCB air concentrations. ∑7PCBs monthly averaged concentration varied from 31 to 76 pg m−3. Concentrations in the gas phase (21-72 pg m−3) were higher than those in the particulate phase (3-10 pg m−3). Advection of air masses and re-volatilization from local sources seem to play a dominant role as drivers of PCB atmospheric concentrations in the area. Indications of seasonal variation affecting PCB congener patterns and the gas/particulate partitioning were found. Modeling calculations suggest a predominant importance of the wet deposition in this region (1 μg m−2 yr−1 ∑7PCBs yearly total wet deposition flux; 650-2400 pg L−1 rainwater concentrations).  相似文献   

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