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1.
Polychlorinated biphenyls (PCBs) were analyzed in sediment and oyster samples from coastal sites inside Manila Bay. Concentrations for 13 individual PCB congeners and total PCBs are reported herein. Median ΣPCB concentration in sediments was 0.46 ng g?1 dry weight (range 0.10–1.5 ng g?1) and in oysters it was 15 ng g?1 dry weight (range 7–73 ng g?1). The most contaminated areas of the bay were the coastal zones of Metropolitan Manila and Bulacan province. A significant correlation (p < 0.01) was found between ΣPCB concentrations in oysters and in sediments. PCB concentrations measured in the bay sediments were below acute toxic levels to marine biota. Nevertheless, consumption of oysters by human population living around the bay might originate ΣPCB intake rates estimated at about 2.5 times lower than the tolerance limit. Further environmental surveillance is recommended in order to prevent public health risks that may be posed by these chemicals.  相似文献   

2.
The concentrations of marker PCBs (28, 52, 101, 118, 138, 153, 180) in fish have been assessed with GC-MS: an average concentration of 540 ng-PCB g−1 fat (5.02 ng-PCB g−1 wet weight) was observed. The average concentration of PCDD/Fs, assessed with the CALUX bioassay, amounted to 64 pg-CALUX-TEQ g−1 fat (0.58 pg-CALUX-TEQ g−1 wet weight) and that of PCDD/Fs + dioxin-like PCBs amounted to 131 pg-CALUX-TEQ g−1 fat (1.18 pg-CALUX-TEQ g−1 wet weight). Results of the PCB congeners analyses show that PCB-153 is the most abundant congener in almost all samples, with also main contributions of the 138- and 180-congeners. For some species such as the sand sole and lemon sole, a fairly constant PCB content, independent of the fat percentage, was observed. For a second group of species such as whelks, cod, and whiting, a positive correlation was observed between their PCB concentration (ng g−1 fat) and their % of fat. The relationship between marker PCBs and PCDD/Fs concentrations, when plotted on a log scale, fits a straight line (correlation coefficient r = 0.83). With our results on fish and literature data for other food products, intake of marker PCBs and PCDD/Fs could be calculated for the adult population in Belgium (19–60 years old). The Total Daily Intake (TDI) of marker PCBs (ng-PCB day−1) ranges between 1690 and 2210. The TDI of PCDD/Fs (pg-CALUX day−1) ranges between 80.5 and 122, that of PCDD/Fs + dioxin-like PCBs amounts to 151. When PCDD/Fs in fish are assessed with GC-HRMS, the TDI can be lower. The relative importance of fish regarding marker PCB intake amounts to 15–19%, while regarding PCDD/Fs intake it amounts to 34–51%. Using TDI, the body burden evolution of marker PCBs and PCDD/Fs, with age has been calculated.  相似文献   

3.

Objectives

After cargo with PCB-containing transformer oil waste was damaged in heavy seas, the vessel crew exposed to PCB developed itching and acne-form eruption of the skin. The objective of our study was to analyse this work-related incident and its effects on health.

Methods

Air and wipe test samples were taken in the ship for analysis of PCB (28/52/101/138/153/180); clinical investigations of all seafarers (n = 6) included lung function, chest X-ray, clinical chemistry and biomonitoring (plasma PCBs, chlorophenols in urine) measured after a latency of 7 weeks. The biomonitoring data were adjusted according to age-related reference values and validated against controls (n = 96).

Results

Biomonitoring showed elevated PCB-28-/52/-102/-138 congeners (mean 1.16/0.91/136, ∑PCB: 5.82 μg/l), which correlates with the dust samples from the cargo hold (∑PCB. 9,440 mg/m2) and with 6.1 and 5.0 μg/m3 in stern and bow cargo air samples. IgE elevation in two seafarers and substantial blood sedimentation rate increase with anaemia or pulmonary emphysema were unlikely to be caused by PCB exposure. Although two members showed slightly elevated airway resistance values, other lung function parameters were normal and reactive airways dysfunction syndrome due to PCBs could be excluded. Elevated chlorophenols in urine could contribute to the manifestation of chloracne.

Conclusions

PCB-52/-101/-138 found in plasma and in air samples confirm exposure to PCB. Acne-form skin eruptions were from occupational exposure to polychlorinated biphenyls in the spilt transformer oil. There were no other abnormal findings in medical and clinical examinations that could be attributed to PCBs. This does not exclude possible long-term effects.  相似文献   

4.
Polychlorinated biphenyl compounds (PCBs) were analyzed in sediments and clams’ soft tissues from sampling sites in the Mekong River delta from the border with Cambodia to the coast of South China Sea. Concentrations of 13 individual PCB congeners are reported. Median concentration of ΣPCB congeners was 0.279 ng g−1 dry weight (range 0.106–2.016 ng g−1 dry weight) in sediments, and 5.20 ng g−1 dry weight (range 1.89–19.37 ng g−1) in clams. Distribution and bioaccumulation of PCBs in the delta are discussed. It is concluded that in the Mekong River delta PCB concentrations were generally lower than in other regions of Vietnam and their likely sources have been waste discharges from repair workshops and other facilities in the delta cities.  相似文献   

5.
The concentration and major sources of polychlorinated biphenyls (PCBs) were evaluated in the sediments from a special environmental protection area located near a transformer maintenance and repair facility (TMRF) in Ankara, Turkey. ∑PCB concentrations analyzed on Aroclor and congener basis (seven indicator congeners) ranged from 0.1 to 84.2 and 0.1 to 21.7 ng/g dry weight, respectively. Results show that higher total PCB concentrations were localized around one of the drainage channels of the TMRF. Identity and contribution of PCB sources were predicted using a chemical mass balance (CMB) based receptor model. The CMB model typically identified Aroclor 1260, the PCB mixture frequently used in transformers, as the major PCB source confirming the effect of the TMRF on the area. Poor prediction of some sample congener profiles suggest presence of environmental degradation mechanisms such as volatilization and differential solubilization of lower chlorinated congeners from sediments.  相似文献   

6.
Levels of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were measured in 53 human adipose tissue samples. The samples consisted of adipose tissue from 31 men and 22 women having a mean age of 53 years. No information about diet or occupational exposure was collected. Cleanup was performed using a glass column containing acidified silica, deactivated alumina, and anhydrous sodium sulphate. Subsequently, samples were analyzed by high-resolution gas chromatography/tandem mass spectrometry. PBDE concentrations (sum of BDEs 28, 47, 99, 100, 154, 153, and 183) ranged between 1.23 and 57.2 ng g−1 lipid weight and were comparable with levels in samples from other European countries. The sum of seven International Council for the Exploration of the Sea (ICES) indicator PCB congeners (PCBs 28, 52, 101, 118, 138, 153, and 180) ranged from 126 to 2090 ng g−1 lipid weight. No age dependency was found for PBDEs (Pearson correlation −0.023, p = 0.873), whereas PCBs showed higher correlation coefficients with age (Pearson correlation 0.613, p < 0.0005). There was no relationship between PBDE and PCB levels (Pearson correlation −0.010, p = 0.943).  相似文献   

7.
Street dust and surface soil samples in urban areas of Dalian, a coastal city in Liaoning Province, China, were collected and analyzed for 25 polycyclic aromatic hydrocarbons (PAHs). The concentrations, distribution, and sources of PAHs in dust and soil were determined. The concentrations of total PAHs in street dust ranged between 1890 and 17,070 ng/g (dry weight), with an average of 7460 ng/g, whereas the concentrations of total PAHs in surface soil varied greatly, from 650 to 28,900 ng/g, with a mean value of 6440 ng/g. Statistical paired t-test confirmed that total PAH concentrations have no significant difference between street dust and surface soil. Mean PAH concentrations in two type samples were much higher at industrial sites than at business/residential or garden sites. PAHs were dominated by higher molecular weight PAH (4- to 6-ring) homologues, which accounted for about 73% and 72% of total PAHs in street dust and surface soil, respectively. Principal component analysis was used in source apportionment of PAHs in dust and soil. Pyrogenic and petrogenic sources contributed 70% and 22.4% of total PAHs in street dusts, and fossil fuel (coal and petroleum) and biomass combustion accounted for 64.4% and 5.6% of total PAHs in pyrogenic sources, respectively. In surface soil, total PAHs were dominated by pyrogenic sources. The diagnostic ratios of benz[a]anthracene/chrysene confirmed that PAHs in street dust and surface soil of a Dalian urban zone might come mostly from the emission of local sources.  相似文献   

8.
Changes in PCB serum concentrations among capacitor manufacturing workers.   总被引:2,自引:0,他引:2  
To assess the elimination of PCBs in humans, PCB concentrations in serum from 165 capacitor manufacturing workers were measured twice within a 46-month interval (March 1976-December 1979). Use of PCBs at the facility was entirely eliminated in 1977. PCB congeners with lower chlorination (LPCBs--mainly tri- and tetrachlorobiphenyls) had decreased in concentration, with six of the LPCB 7 peaks observed by packed column GC showing average reductions of 25-90%. Higher chlorinated PCBs did not decrease significantly as a whole, although three of the six constituent congener peaks showed some decline (15-25%). As expected, decreases in PCB congener concentrations were associated with chlorine substitution configurations known to be amenable to metabolism.  相似文献   

9.
This study characterizes the elemental composition of street dust and soils in Avilés (N. Spain), a medium-size city of approximately eighty thousand inhabitants, where industrial activities and traffic strongly affect heavy metal distribution. A total of 112 samples of street dust were collected within a 7-km2 area, encompassing residential and industrial sites (ferrous and non-ferrous plants). Elevated geometric mean concentrations of zinc (4,892 μg · g−1), cadmium (22.3 μg · g−1), and mercury (2.56 μg · g−1) in street dust were found in samples located near industrial areas. Two types of anthropic influence were distinguishable: the first and most important one is that related to metallurgical activity and transportation of raw materials for local industries. Secondly, exhaust emissions from traffic are an important source of lead concentration in areas with high vehicular density (geometric mean: 514 μg · g−1). The zinc content in the dust samples decreased with the distance from a zinc smelter located in the northern part of the city. The same trend was found for other elements in association with zinc in the raw materials used by the smelter, such as cadmium and mercury. A simultaneous research campaign of urban soils, that involved the collection of 40 samples from a 10-km2 area, revealed geometric mean concentrations of 376 μg · g−1 Zn, 2.16 μg · g−1 Cd, 0.57 μg · g−1 Hg, and 149 μg · g−1 Pb, and distribution patterns almost identical to those found for street dust. Received: 22 January 2002/Accepted: 24 July 2002  相似文献   

10.
Preremediation studies at Crab Orchard National Wildlife Refuge (CONWR) revealed statistically significant accumulations of polychlorinated biphenyls (PCBs) and effects in starling chicks (Sturnus vulgaris) from contaminated sites, including decreased nest attentiveness, decreased fledging success, and an increase in chick mortality. Although the expected route of exposure for starling chicks is thought to be via diet, this has not previously been documented at CONWR. The purpose of this study was to develop an equation to predict starling chick carcass PCB concentrations from PCB concentrations in ingested animal matter. During 1995 and 1996, stomach contents from 14 and 22 starling chicks collected from contaminated and reference sites, respectively, were evaluated. Animal, plant, and mineral matter in the stomach contents were separated and animal matter from stomachs of individuals from the same nest were combined, dried, and percent dry weight calculated. Composite samples of animal matter were then analyzed for the presence of PCBs (Aroclor 1254). Stomach contents were primarily composed of animal matter (76%), and the percent animal matter in the stomachs did not differ significantly among locations (range = 38.4% to 100%). The mean PCB concentration in composite samples of animal matter from stomachs of chicks collected from contaminated sites (1.82 ± 1.17 mg/kg) was significantly greater than the concentrations in composite samples from two reference locations (<0.24 mg/kg). PCB concentrations in stomach contents were correlated (Pearson correlation coefficient = 0.91, p < 0.005) with concentrations in carcasses of chicks from which the stomachs had been collected. The regression Y = 6.19 × X1,398, where Y = starling chick carcass PCB concentration and X = starling stomach animal matter PCB concentration, indicated that PCB concentrations in consumed animal matter accounted for 82% of the variability in starling carcass concentrations. Received: 1 February 1999/Accepted: 24 April 1999  相似文献   

11.
A total of 10 surface soil samples covering the whole territory of Linfen city were collected for analysis the 144 polychlorinated biphenyls (PCBs). The total PCBs concentration ranged from 0.2 to 3.4 ng g−1 in urban soil and 0.5 to 14.8 ng g−1 in industrial plant soil. Furthermore, increasing PCBs contamination was observed in northeast Linfen because of the distribution of industrial plants. Principal component analysis (PCA) revealed that the major source of PCBs in Linfen may be potentially associated with commercial #1 PCB through the long-range transmission. In total, PCBs were not a severe contamination in Linfen from current results.  相似文献   

12.
Seven “target” PCB levels were determined and compared in waterbird eggs, in their prey, and in water at Lake Kerkini, northern Greece, to investigate PCB bioaccumulation patterns and to define the best bioindicator of target PCBs for this area. PCBs were analysed from eggs of Phalacrocorax carbo, Podiceps cristatus, Ardea cinerea, Egretta garzetta, and Nycticorax nycticorax and from prey types Alburnus alburnus, Rutilus rutilus, Lepomis gibbosus. Carassius auratus, and Rana sp. PCBs analysed were detected in all bird eggs, prey, and water but contamination patterns differed among these sample types. The lipid-corrected geometric means of the congeners analysed were significantly different among most bird species and among some prey species. PCB congeners 118, 138, 153, and 180 accounted for around 80% of the total PCB contamination in bird egg samples. Percent congener concentrations of high-chlorinated PCBs tended to increase from water through prey to most bird egg samples whereas the low chlorinated PCBs (28 and 52) decreased. Bioaccumulation factors (BAFs) also exhibited an increasing trend for higher chlorinated PCBs from prey types to bird eggs. The greatest BAFs of six of the congeners were shared between Phalacrocorax carbo and Ardea cinerea. Among prey, the BAFs of four PCBs were highest in Lepomis gibbosus. Biomagnification factors varied between 1.01 and 39.57. In contrast to low chlorinated PCBs, high chlorinated congeners biomagnified considerably through fish prey. The highest biomagnification took place in Phalacrocorax carbo. No relationship was found between the lipid content of samples and BAFs of PCBs probably due to biotransformation differences of the congeners in the biota sampled. Due to the greatest PCB concentrations especially of the higher chlorinated PCBs in the eggs of Phalacrocorax carbo and its considerable bioaccumulation tendencies, it is proposed as the best PCB biomonitor of target PCBs at Lake Kerkini. Lepomis gibbosus had the highest concentrations of most congeners and exhibited the greatest bioaccumulative properties among prey and can be used as an alternative biomonitor.  相似文献   

13.
In the Faroe Islands in the North Atlantic, the traditional diet includes pilot whale meat and blubber and other marine food. Fatty fish and blubber of mammals may contain high concentrations of organohalogen substances (OHSs). Elevated levels of OHSs have been reported from the Faroe Islands, first documented in breast milk samples obtained in 1987. The aim of this study was to determine the concentrations of hydroxylated polychlorinated biphenyls (OH-PCBs) and polychlorinated biphenyls (PCBs) in serum samples from pregnant Faroese women known to differ in their dietary habits. High concentrations of OH-PCBs and PCBs were found in part of the human serum samples analyzed, and the relative OH-PCB and PCB congener distributions were similar to those observed elsewhere. There was a wide span between the lowest and highest OH-PCB and PCB concentrations in the serum samples analyzed, with ranges of 19-1,800 ng/g lipid weight (lw) and 150-22,000 ng/g lw, respectively. The ratio of sigmaOH-PCB/sigmaPCB averaged about 10% and varied little. 4-Hydroxy-2,2,3,4,5,5,6-heptachlorobiphenyl was the most abundant OH-PCB metabolite in all samples analyzed, with four other OH-PCB congeners as dominating metabolites in the serum. More than 25 additional OH-PCBs were indicated. This study confirms the presence of high concentrations of organohalogen substances in populations or areas far removed from their sources.  相似文献   

14.
A study was conducted to address the question of how fish consumption, occupation, and outdoor air affected serum PCB concentrations and congener patterns among 139 Native American men living near three hazardous waste sites. They were interviewed about their residential, occupational, and dietary histories, and donated 20 ml of venous blood for congener-specific PCB analysis. The similarity in the congener pattern between that found in the serum and that detected in local environmental samples was measured by calculating the Euclidean distance between them. The results indicated that serum PCB concentrations were positively associated with cumulative lifetime exposures to PCBs from local fish consumption and occupation. However, participants who lived in the last 10 years at Raquette Point, which is the area of the Reserve closest to the hazardous waste sites and the only location where elevated levels of PCBs were found in outdoor air, did not have higher serum PCB concentrations than participants who lived elsewhere at Akwesasne. Regarding pattern matching, Mohawk men with the greatest cumulative lifetime exposure to PCBs from local fish consumption had a serum PCB congener pattern that more closely resembled that in fish caught off-shore from one of the hazardous waste sites than did men who ate less local fish. Similarly, Mohawk men who were occupationally exposed to PCBs were more likely than those without occupational exposure to have a serum PCB congener pattern that was similar to that of Aroclor 1248, the commercial PCB mixture used locally. The serum PCB congener pattern of Raquette Point residents more closely resembled the pattern in outdoor air only if the men ate relatively few local fish. The study is among the first to demonstrate that outdoor air may affect serum PCB congener patterns, at least in the absence of heavy fish consumption.  相似文献   

15.
The aim of this study was to evaluate sediments of the Dniester River, in the former Soviet republic of Moldova, for the occurrence of agricultural pesticides, polychlorinated biphenyls (PCBs), and heavy metals. In October 2001, sediment samples were collected at three locations of the Dniester River: upstream, downstream, and at the tributary of the River Byk. DDT and its metabolites were observed most frequently. Total DDT sediment concentrations ranged from 8.2 to 34.7 ng/g dry weight with the highest average concentration detected at the tributary location. Heptachlor epoxide (< 0.2–3.0 ng/g dry weight), chlordane (< 0.1–6.1 ng/g dry weight), endrin (< 0.2–2.5 ng/g dry weight), phosalone (< 0.2–1.1 ng/g dry weight), and methylparathion (< 0.2–16.8 ng/g dry weight) were also detected. Total PCB concentrations observed in sediments ranged from 68 to 763 ng/g dry wt. Total average PCB concentrations were significantly (p ≤ 0.004) higher for sediments from the downstream sampling sites compared to the upstream samples. Tetra- and trichlorobiphenyls accounted for 84 and 88% of the total residues measured in the downstream and tributary locations, respectively. In contrast, heptachlorobiphenyls were the prevailing homologues in sediments from the upstream sampling site, contributing 51% of the total PCB concentration. Predominant PCB homologues were: trichlorobiphenyl congener 28 and 37, tetrachlorobiphenyl congeners 44, 49, 52, 74, 77, and 81, and heptachlorobiphenyl congener 170. Sediment concentrations of ΣDDE (19.7 ng/g dry weight) in the tributary, heptachlor epoxide (3.0 ng/g dry weight) in the downstream, and nickel (128–170 μg/g dry weight) in all locations exceeded Probable Effect Levels (PELs) established for sediment quality in fresh water, indicating probable environmental stress and the potential for adverse effects to benthic organisms in the Dniester River.  相似文献   

16.
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.  相似文献   

17.
PCB Congener Accumulation by Periphyton, Herbivores, and Omnivores   总被引:1,自引:0,他引:1  
The concentrations of 20 polychlorinated biphenyl (PCB) congeners were measured in periphyton, herbivorous fish (stoneroller minnows, Campostoma anomalum), and omnivorous fish (striped shiners, Luxilus chrysocephalus) in an industrially contaminated stream and a reference stream in eastern Tennessee. The sum of the concentrations of the 20 congeners, normalized by dry mass, was one to two orders of magnitude higher in stonerollers and shiners than in periphyton. Normalizing PCB concentrations by lipid mass reduced concentration differences between periphyton and stonerollers, but PCBs per unit lipid in stonerollers were still 50–350% higher than those in periphyton. Shiners had significantly higher lipid-specific PCB concentrations than did stonerollers, so a trophic hierarchy of primary producer < herbivore < omnivore was evident in lipid-specific PCB concentrations. Differences in lipid type, exposure duration, and exposure sources may account for the trophic-level differences in total PCBs. Congener profiles were roughly similar in periphyton, stonerollers, and shiners: five congeners (IUPAC numbers 101, 110, 138, 153, and 180) constituted >60% of the total mass of PCBs analyzed in all three trophic levels. However, stoneroller and shiner tissue was enriched in congeners 153, 118, and 187 relative to periphyton; congeners 153 and 187 are resistant to metabolic breakdown by monooxygenases found in fish liver. Principal component analysis of congener percentages separated periphyton from fish and distinguished between sampling locations. Received: 16 August 1996/Revised: 3 November 1996  相似文献   

18.
Polychlorinated biphenyl (PCB) and OCP concentrations were determined in the livers of two deep-sea fish species, roughsnout grenadier and hollowsnout grenadier, from the Adriatic Sea. In both species, contaminant concentrations were in the following order: PCBs>DDTs>>HCB. Contaminant load was higher in roughsnout grenadier (PCB: 12,327 ng g−1; DDTs: 5357 ng g−1; HCB: 13.1 ng g−1) than in hollowsnout grenadier (PCB: 1234 ng g−1; DDTs: 763 ng g−1; HCB 6.3 ng g−1). PCB patterns were dominated by higher chlorinated congeners (hexa-CBs: 50.3-52.1%, hepta-CBs: 29.6-35.5%, penta-CBs: 8.0-11.1% and octa-CBs :5.2-5.4%). PCBs 138, 153 180 and 187 were the most abundant. Regarding the DDT pattern, p,p′-DDE was prevalent in both species (roughsnout grenadier: 99.7%, hollowsnout grenadier: 90%), suggesting no recent DDT input. In both species, the total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalent (TEQ) concentrations (roughsnout grenadier: mean 43.77 pg/g, hollowsnout grenadier: mean 20.49 pg/g), calculated from non- and mono-ortho PCBs, reached those encountered in marine organisms at higher levels in the trophic chain.  相似文献   

19.
Primitive electronic-waste recycling resulted in serious pollution of polychlorinated biphenyls (PCBs) in the environment of Guiyu, China. We aimed to assess body burdens of PCBs and potential health risks for neonates. Umbilical cord blood (UCB) samples were collected from Guiyu, and the control area of Chaonan, China. PCBs in UCB were determined by gas chromatography coupled with mass spectrometry. The median ∑PCBs concentration was 338.56 ng g−1 lipid in UCB samples from Guiyu, vs. 140.16 ng g−1 lipid in samples from Chaonan. Mothers′ involvement in electronic-waste recycling activities and house used as family workshop were the significant factors that contributed to ∑PCBs level. Some individual PCB congeners were found to correlate with reduced neonatal height, weight, Apgar scores, gestational age, and body mass index (BMI). Difference of ∑PCBs level was found between normal birth and adverse birth outcomes. Neonates from Guiyu are exposed to high levels of PCBs; prenatal exposure to PCBs appears to influence neonatal health, but still needs further confirmation.  相似文献   

20.
To assess the level of polychlorinated biphenyl (PCB) contamination and identify their sources, surface sediments were collected from selected locations along Nakdong River, Korea, and analyzed for 209 PCB congeners using high-resolution gas chromatography/high-resolution mass spectroscopy. PCB levels ranged from 0.124 to 79.2 ng/g dry weight (coplanar PCBs 0.295 to 5720 pg/g dry), which were similar to those of three other major rivers (Han, Geum, and Youngsan rivers) in Korea but slightly lower than those in neighboring countries. Regarding homologue composition, tetra-CBs were most abundant in most samples, but some samples with much higher PCBs concentrations had relatively lower proportions of tetra-CBs and higher proportions of penta- to hepta-CBs. To identify the sources of PCBs in sediment samples, principal component analysis/absolute principal component scores (PCA/APCS), positive matrix factorization (PMF), and multiple linear regression (MLR) were used with the congener composition of aroclors (1242, 1248, 1254, and 1260) and the flue gas of waste incinerators (data obtained from a previous article) as source profiles. Results showed that the three models showed similar source apportionments. Most sediment samples with lower PCB concentrations had higher proportions of incineration-derived materials, and some sediment samples with much higher PCB concentrations had higher proportions of aroclor 1260. This occurred because many industrial facilities, such as landfill leachate–treatment facilities, were gathered around sampling points with high PCB concentrations, and high-chlorinated PCBs are more stable in the elution process of landfill leachate than the incineration process. PCB concentrations estimated by APCS, PMF, and MLR were similar to the measured values with coefficients of determination ranging from 0.77 to 0.99.  相似文献   

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