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1.
The River Yamuna originates from the Yamunotri glacier of the Himalayas and travels 22 km in the Delhi region. The river is used for various purposes in Delhi including drinking water supply. Twenty-eight polychlorinated biphenyls (PCBs) congeners were measured in bank sediments along the river, and their ecotoxicological risk was evaluated. Concentrations of ∑28PCBs varied from 0.20–21.16 ng g?1 (dry wt.) with mean and median values of 6.63 ng g?1 and 5.84 ng g?1 (±0.69 ng g?1), respectively. The concentration of 12 dl-PCBs concentrations varied from 0.04–2.86 ng g?1 with a mean of 1.04 ± 0.11 ng g?1, and their toxic equivalency ranged between <0.01–28.67 pg WHO-TEQ g?1 with a mean of 10.77 ± 1.06 pg WHO-TEQ g?1. CB-37, CB-44, CB-114, and CB-118 congeners were dominant among all PCBs congeners. The tri-PCBs (49%) were the main contributors to the PCB homolog followed by tetra-PCBs (35%), and penta-PCB (14%). Because there are no environmental guidelines in India for PCBs in river and marine sediments, concentrations of PCBs and their toxic equivalents were compared in a screening-level assessment with established freshwater sediment quality guidelines and found lower than those guideline values, which suggests no adverse ecotoxicological effect.  相似文献   

2.
In this paper, a simple and novel method for the determination of polychlorinated biphenyls (PCBs), using silver nanoparticles (AgNPs) as a resonance light scattering (RLS) probe, is proposed. Under optimized conditions, there existed linear relationships between the enhancing RLS intensity of the system and the concentrations of PCBs in the range 8.0 × 10?8?1.0 × 10?6 g mL?1 for 2,4,4′‐trichlorbiphenyl (PCB28), 9.0 × 10?8?1.0 × 10?6 g mL?1 for 2,2′,5,5′‐tetrachlorbiphenyl (PCB52) and 4.0 × 10?8?1.0 × 10?6 g mL?1 for 3,3′,4,4′‐tetrachlorobiphenyl (PCB77). The corresponding detection limits (S/N = 3) were 2.6 × 10?8 g mL?1 for PCB28, 3.3 × 10?8 g mL?1 for PCB52 and 6.3 × 10?9 g mL?1 for PCB77, respectively. Finally, the mechanism of RLS enhancement was also studied. The results indicated that PCBs were adsorbed on the surface of AgNPs to form larger AgNP–PCB aggregates, resulting in the RLS enhancement of the system. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

3.
The uptake of persistent organic pollutants by plants   总被引:1,自引:0,他引:1  
In a field experiment, the transfer of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) from contaminated soil to maize (Zea mays L.), sunflower (Helianthus annuus), poplar (Populus nigra × P. maximowiczii) and willow (Salix × smithiana) and the distribution of PCB congeners in maize and sunflower was investigated. The former waste incinerator in Hradec Králové (Czech Republic) was chosen for the experiment. Results of plot screening showed heterogenous contamination by PCBs and PAHs. PCB soil contamination was evidently caused by Delor 106 or Aroclor 1260 stocking and PAH contamination by chemicals containing fluoranthene, benzo/b/fluoranthene, phenanthrene and pyrene. Tested plants were planted on a contaminated field site, in soil contaminated with 1530 μg/kg of total PCBs and 0.138 and 3.42 mg/kg of total PAHs. The results show that maize and sunflower roots accumulated the most PCBs from soil. These plants accumulated hexa- and heptachlorobiphenyl congeners more than tri-, tetra-, and pentachlorobiphenyl congeners. Total concentrations of PAHs in tested plants ranged from 0.096 to 1.34 mg/kg. The highest phenanthrene concentration was found in aboveground biomass of sunflower and the highest concentration of pyrene, in maize roots.  相似文献   

4.
Contamination of food chain by Polychlorinated biphenyls through use of pesticides, electric and industrial waste poses human health risk. In previous studies, PCB species were stated as endocrine disrupting pollutants and showed toxic health effects like cancerous and noncancerous in animals. The aim of this study was to investigate the levels of PCBs and its toxicity equivalence in food item from plant source to evaluate the health risk in Khanewal and Multan, Pakistan. Samples were collected and processed for further analysis of PCB species through GC/MS after extraction and clean up. The mean concentrations of PCBs ranged as 2.71–151.67 ng/g in beans and grains and 2.30–97.00 ng/g dry weight in vegetables and were lower than 200–3000 ng/g PCBs recommended by FDA tolerance level for all foods. The mean concentrations of two NDL-PCB species detected in all vegetables, beans and grains except S.indicum and T.aestivum were lower than maximum allowable concentration of non-dioxin like PCBs i.e. 40ngg?1 reported by European Commission. Mean TEQ of sum of 14 PCB species ranged as 1.52–5.91 ng-WHO-TEQg?1 in vegetables and 1.46–10.04 ng-WHO-TEQg?1 in beans and grains. The present study concluded that the mean concentrations and mean TEQs of PCB species in most of the vegetables, beans and grains were found safe but due to higher consumption rate of some vegetables and grains, posed the moderate level of risk for human health. This study emphasizes on an implement of the strict rules regarding the use of restricted chemicals to diminish the effluence in food chains. Current research will be useful in up gradation of effective measures to reduce the poisonous contribution of PCB sources and the sustainability of terrestrial ecosystem in the country.  相似文献   

5.
Concentrations of 28 polychlorinated biphenyls (PCBs) were assessed in soils from the Midway Atoll in the central North Pacific Ocean. The analytical procedure involved the application of accelerated solvent extraction (ASE) and gas chromatography coupled with ion trap mass spectrometric detection (GC/ITMS) for identification and quantification. Among the 28 PCB congeners studied, 26 of them, except CB195 and CB209, were detected in the analyzed samples at different frequencies. The total concentrations of 28 indicator PCBs (ΣPCBs) ranged from 2.6 to 148.8 ng g−1 with an average value of 50.7 ng g−1 and median of 39.5 ng g−1. Sources and congeners’ pattern of PCB were investigated in the soil of Midway Atoll. The principal component analysis indicated that the compositions of PCBs in most of the soil samples were similar. The total concentrations of PCBs were used to assess the cancer risk probabilities in humans via ingestion, dermal contact and inhalation of soil particles. Very low cancer risk was found in all soil samples caused by ΣPCBs.  相似文献   

6.
A comprehensive congener specific assessment of polychlorinated biphenyls (PCBs) was conducted for the first time in Bangladesh. All 209 PCB congeners in the surficial coastal sediments from the coastal areas of Bangladesh were analyzed by GC-MS/MS. The total concentrations of PCBs (∑PCBs) varied from 5.27 to 92.21 and 4.61 to 105.3 ng/g dw in winter and summer, respectively, and the ranges were comparable to or higher than those recorded in the sediments from the coastal areas of India, Korea, China, and Taiwan. The seasonal difference in the levels of PCBs was not statistically significant (p > 0.05). The spatial distribution revealed that the areas with recent urbanization and industrialization (Chittagong, Cox’s Bazar and Sundarbans) were more contaminated with PCBs than the unindustrialized area (Meghna Estuary). Moderately chlorinated (4–6 Cl) homologs dominated PCB profiles. A set of congeners based on their detection frequencies and abundance were identified and categorized as potential environmental marker PCBs, which can be used for the future selective monitoring studies where there would be limitations on whole congener assessment. Ecotoxicologically, the sedimentary PCB concentrations exceeded some of the existing environmental quality standards, suggesting a potential threat to the aquatic organisms in the Bangladeshi coastal areas.  相似文献   

7.
Concentrations of Σ15 PCBs in sediments of the Forcados River, Nigeria, were determined in 2012 to provide information on the profile, sources and ecotoxicological risks of PCBs in the sediment. The screening concentrations of PCBs were quantified using a gas chromatograph equipped with a Ni-63 electron capture detector. The concentrations of the Σ15 PCBs ranged from 2.7 to 202.3 µg kg???1 with a mean concentration of 46.5 µg kg???1. The composition of PCB congeners was clearly dominated by octa-PCBs, hepta-PCBs and hexa-PCBs, constituting 68.1% to 93.7%, respectively, of the total amounts of PCBs. All sites had Σ15 PCB levels below the prescribed probable effect concentrations, and therefore no adverse effects are expected for the majority of sediment-dwelling organisms of the Forcados River system.  相似文献   

8.
Polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were analysed from sediment samples collected in 2012 from rivers, surface runoff canals and estuaries in three highly urbanised catchments in durban, KwaZulu-Natal, South Africa. PAHs were ubiquitous, at concentrations between 36–6 800 ng g?1 dry mass (dm). Congener ratio diagnosis suggests the PAHs were derived predominantly from pyrogenic sources. Four OCPs and/or their metabolites were detected at varying frequencies and concentrations. Of these, dichlorodiphenyltrichloroethane (ddT) and metabolites were most frequently detected and were at a high concentration in sediment in some systems. Toxaphene was detected at a high concentration at some sites. The total PCB concentration varied widely, from below the method detection limit to 110 ng g?1 (dm). Based on the comparison of chemical concentrations to international sediment quality guidelines, PAH, OCP and PCB concentrations in most sediment samples posed a low risk to sediment-dwelling organisms. However, in some instances the risk was moderate or high. It is recommended that these compounds be monitored more frequently and comprehensively in aquatic ecosystems to better understand the ecological and human health implications.  相似文献   

9.
This study assessed the mixture health risk for the residents of China's Lake Taihu region posed by a Persistent Organic Pollutants (POPs) mixture of dichloro-diphenyl-trichloroethane (DDT) and hexachlorocyclohexane (HCH). Multiple-pathway exposure models were used for exposure assessment in order to estimate the DDT and HCH exposure dose. The DDT and HCH PBPK models were developed and used for consequence assessment in order to analyze the pollutant distribution and accumulation process in human tissues. The tissue dose hazard index (HI) was used to estimate the mixture health risk. The results showed that the total exposure doses for male residents and female residents were 4.01 × 10? 4~ 7.67 × 10? 3 mg/kg/day and 3.73 × 10? 4~ 6.75 × 10? 3 mg/kg/day for DDT, respectively, and 3.78 × 10? 4~ 5.14 × 10? 3 mg/kg/day and 3.53 × 10? 4~ 4.66 × 10? 3 mg/kg/day for HCH, respectively. The maximum tissue concentrations in fat for male and female residents reached 110.51 mg/l and 97.21 mg/l for DDT, respectively, and 189.66 mg/l and 171.72 mg/l for HCH, respectively. The tissue dose hazard indexes for male and female residents were 0.1472 ~ 2.4990 and 0.1377 ~ 2.2230, respectively, and the probabilities of the risk exceeding the acceptable risk (HI = 1) for male and female were 24.60% and 16.51%, respectively.  相似文献   

10.
The concentrations of PAHs in four species of fish (Common carp, Crucian carp, Bighead carp, and Topmouth culter) from Lake Taihu were tested, and the human health risks of PAHs by fish consumption were evaluated. Results showed that concentrations of PAHs in fish from Lake Taihu were 52.5–247.6 ng/g wet weight (ww), and the BaP equivalent concentrations of total PAHs (B[a]Peq) were 0.2–0.6 ng/g ww, which were less than the screening value of 2.6 ng/g wet for human consumption. The concentration sequences of PAHs in fish from Lake Taihu from high to low were Bighead carp > Crucian carp > Common carp > Topmouth culter. The human health risk level of PAHs by fish consumption was 5.8 ± 2.5 × 10?6, which was less than the maximum acceptable risk level of 1 × 10?5 for human health set by the U.S. Environmental Protection Agency. The tissue residue guideline (TRG) of PAHs for protecting aquatic wildlife was 1.3 mg/kg diet ww, which was higher than the concentrations of PAHs in fish from Lake Taihu. The results indicated that fish consumption from Lake Taihu would not cause health risk or harmful effects on wildlife that consume aquatic biota.  相似文献   

11.
Levels of polychlorinated biphenyls (PCBs) congeners and dichlorodiphenyltrichloroethane and its metabolites (DDTs) were measured in 18 species of fish, crab, shrimp, and bivalve samples collected from the northern region of the Persian Gulf in Iran. The levels of ∑PCBs varied from 259.92 ± 31.04 ng/g to 1648.88 ± 176.96 ng/g in lipid weight. CB118 showed the highest concentration. ∑DDT variations ranged from ND to 570.45 ± 806.74 ng/g in lipid weight. Health risk was assessed by estimating both dietary intakes and screening values (SVs). Daily intake levels were much lower than the Food and Agriculture Organization (FAO)/World Health Organization (WHO) standards for PCBs and DDTs. Based on an average bodyweight of 73 kg and consumption rates of 0.055 kg/person. day, the SVs for the carcinogen and non-carcinogen effects of PCB and DDT were calculated. Average concentrations of PCBs and DDTs showed that the levels of PCBs exceeded the established SV for carcinogens. This finding suggests the need to enhance risk management regarding seafood consumption through public advisory.  相似文献   

12.
Polychlorinated biphenyls (PCBs) are ubiquitous in the environment. Midway Atoll, located in the North Pacific Ocean, was occupied by the military during and after World War II. However, Midway Atoll has become a national wildlife refuge and home to many different seabirds today, including the black-footed albatross (Diomedea nigripes) (BFAL). The profiles and toxic equivalents (TEQ) of PCB congeners in the plasma and preen oil of BFAL chicks and adults were determined in this study. The concentrations of the total PCBs in the plasma samples of chicks and adults collected in Midway Atoll ranged from 2.3 to 223.8 (mean 80.1) and 22.8 to 504.5 (mean 158.6) ng g-1 (wet weight, ww), respectively. The TEQs ranged from 0.2 to 0.6 (mean 0.4) and 0.4 to 1.6 (mean 0.9) pg g-1 ww, respectively, in the plasma samples of chicks and adults from Midway Atoll. The major congeners in the plasma samples of chicks and adults included PCBs 31, 87, 97, 99, 118, 138, 153, and 180, accounting for 70% of the total PCBs. The concentrations of the total PCBs in the adult preen oil samples ranged from 1693 to 39404 (mean 10122) ng g-1 (ww), of which 97% were PCBs 105, 118, 128, 138, 153, 161, 172, and 183.  相似文献   

13.
The aim of this study was to carry out a bioaccessibility-based risk assessment of polycyclic aromatic hydrocarbons (PAHs) in soils from sites of different anthropogenic activities in Lagos, Nigeria. Using an in vitro gastrointestinal model—Fed Organic Estimation Human Simulation Test method (FOREShT), the concentration of bioaccessible 16 priority US Environmental Protection Agency (USEPA) PAHs in soils were determined. Total concentration of 16 priority USEPA PAHs was also determined. The concentration range was 702–253,922 ng g?1 and 92–760 ng g?1 for total and bioaccessible PAHs, respectively. For persons involved with activities at these sites no health risks were observed, based on bioaccessibility values of PAHs. Mean daily intake of PAHs from these soils were below the oral mean daily intake threshold for PAHs in food. Also, overall estimated theoretical cancer risk (2.5 × 10?09, 6.5 × 10?07, 5.5 × 10?10, 2.7 × 10?09, 6.5 × 10?10, 9.5 × 10?10, 2.0 × 10?09, and 4.1 × 10?07 for the eight sites based on their bioaccessible concentration) for exposure to PAHs in surface soils were below the health guidelines for extreme (1 × 10?04) and normal (1 × 10?06) exposures.  相似文献   

14.
Abstract

This study investigated the distribution, sources, and potential risks of polycyclic aromatic hydrocarbons (PAHs) in coastal waters along over 18,000?km of coastline in China. Concentrations of PAHs in coastal waters ranged from 141.99 to 717.72?ng/L. Approximately 84.38% of sampling sites were determined at moderate PAH pollution level. PAHs in coastal waters at most of sampling sites mainly originated from combustion based on characteristic ratios of PAHs. Ecological risks posed by PAHs in coastal waters were evaluated as high level at 59.38% of sampling sites and moderate level at 40.63% of sampling sites although toxic equivalent quotients of PAHs only ranged from 2.86 to 126.52?ng/L benzo[a]pyrene that was not detected at all sampling sites. Maximal cancer risk/hazard quotient of total PAHs in coastal waters for adults and children reached 6.34?×?10?4/5.85?×?10?2 and 2.25?×?10?3/7.72?×?10?2, respectively. PAHs exerted high cancer risks for children at 31.25% of sampling sites. Health risks posed by PAHs in coastal waters of this study were higher than those of Japan, Belgium, Greece, Italy, Spain, USA, and Australia, but much lower than those of Singapore, Iran, Brazil, and Egypt. These findings indicate that PAH pollution has become a crucial stress affecting the sustainable development of coastal regions.  相似文献   

15.
The concentrations of the 16 U.S. Environmental Protection Agency polycyclic aromatic hydrocarbons (PAHs) were measured in urban street dust with a view to understanding the potential risk to urban residents exposed to street dust, sources, and distribution of the PAHs. Gas chromatography–mass spectrometry was used to measure the concentrations of the PAHs after ultra-sonication with hexane/dichloromethane and clean up. The total concentrations of the ?16 PAHs in the urban street dust from Warri and its environs ranged from 165.1 to 1012 µg kg?1. The isomeric ratios and the PCA indicated that combustion of petroleum and biomass are the major sources of PAHs in Warri and its environs. The total BaP carcinogenic and mutagenic potency concentrations (?BaPTEQ and ?BaPMEQ) were in the range of 0.03 to 219 µg kg?1 and 0.52 to 182 µg kg?1, respectively. The incremental life cancer risk from exposure of the residents of Warri and its environs ranged from 4.07 × 10?7 to 3.11 × 10?3 and 2.13 × 10?7 to 1.49 × 10?3 for the children and adults, respectively, which were higher than the baseline value of acceptable risk of 10?6 (i.e., one case per million people).  相似文献   

16.
Dichlorodiphenyltrichloroethane (DDT), hexachlorocyclohexane (HCH), and their isomers’ levels in residential soils were determined for the assessment of health risk in Korba, India. Observed concentrations of total HCH and total DDT in soils were more or less comparable with other parts of India and the world. ΣHCH and ΣDDT concentrations ranged between 0.9–20 μg kg?1 and 2–315 μg kg?1, respectively, which were lower than recommended soil quality guidelines indicating low ecotoxicological risk. Carcinogenic and non-carcinogenic impacts of HCH and DDT on human populations through soil ingestion were evaluated and presented. The incremental lifetime cancer risk (ILCR) for adults and children ranged between 7.8 × 10?10–1.6 × 10?7 and 4.1 × 10?9–8.2 × 10?7, respectively. Non-cancer health hazard quotient (HQ) ranged between 5.9 × 10?7–1.8 × 10?3 and 3.1 × 10?6–9.4 × 10?3, respectively, for adults and children. The estimated ILCR and HQ were within the safe acceptable limits of 10?6–10?4 and ≤1.0, respectively, indicating low risk to human populations from exposure to organochlorine pesticides (HCH and DDT) in the study area.  相似文献   

17.
Sixteen USEPA priority polycyclic aromatic hydrocarbons (PAHs) were analyzed by gas chromatography–mass spectrometry. Twenty samples were collected from the surface sediments of Haizhou Bay in this survey. This research aimed to identify the PAHs' contamination level, composition pattern, pollution sources, and assess the ecological risk of PAHs. The results showed that the sum of PAH concentrations ranged from 116.6 ng g?1 to 2414.9 ng g?1 (mean: 662.42 ng g?1), which is higher than the reported values for different wetlands worldwide. Three- and four-ring PAHs (accounts for more than 70% of the total PAH content) were predominant in the wetland sediment. The PAHs source distribution in the surface sediments were determined using diagnostic ratio and PCA/MLR. Consequently, multiple PAHs sources were found. Of the total PAH, 79.25% was derived from vehicular emission, 20.75% from coal combustion. The effect range low/effect range median (ERL/ERM) values indicated a low toxicity risk level. However, the fluoranthene concentrations exceeded the ERL level, and even the ERM level, in some stations. The mean effects range–median quotient (M-ERM-Q) suggests a low ecological risk for the PAHs in the sediments.  相似文献   

18.
To investigate the occurrences of polychlorinated biphenyls (PCBs) in suburban vegetable soils of Changchun area, Northeast China, 106 urban vegetable soil samples were collected from Changchun City, Nongan County, Dehui City, Yushu City, Jiutai City, Shuangyang District. We analyzed the concentrations, compositions and sources of 7 PCBs in top soils of Changchun area, and evaluated the non-carcinogenic and carcinogenic risk of PCBs pollution to exposed population. The total concentrations of 7 PCBs ranged from 1.31 to 148 ng/g dry weight (dw) with a mean value of 42.0 ng/g and dominated by Hepta-CBs and Penta-CBs. Principal component analysis (PCA) revealed that PCB pollution in soils of Changchun area mainly related to transportation, vehicle emissions, paints and other industries. Human health risk assessment showed that the cumulative non-carcinogenic and the cumulative carcinogenic risk in children and adults in the industrial land and residential land were acceptable, considering only 7 PCBs homologues were analyzed in this study, the actual risk could be higher.  相似文献   

19.
This study was carried out to assess the dissipation of 17 selected polychlorinated biphenyl (PCBi) congeners in a transformer oil-contaminated soil using bioaugmentation with 2 PCB-degrading bacterial strains, i.e., Pseudomonas spp. S5 and Alcaligenes faecalis, assisted or not by the maize (Zea mays L.) plantation. After 5 and 10 weeks of treatment, the remaining concentrations of the target PCBi congeners in the soil were extracted and measured using GC-MS. Results showed that the bacterial augmentation treatments with Pseudomonas spp. S5 and A. faecalis led to 21.4% and 20.4% reduction in the total concentration of the target PCBs (ΣPCBi), respectively, compared to non-bioaugmented unplanted control soil. The ΣPCBi decreased by 35.8% in the non-bioaugmented planted soil compared with the control. The greatest degradation of the PCB congeners was observed over a 10-week period in the soil inoculated with Pseudomonas spp. S5 and cultivated with maize. Under this treatment, the ΣPCBi decreased from 357 to 119 ng g?1 (66.7% lower) and from 1091 to 520 ng g?1 (52.3% lower). Overall, the results suggested that the combined application of phytoremediation and bioaugmentation was an effective technique to remove PCBs and remediate transformer oil-contaminated soils.  相似文献   

20.
In this paper, a sensitive resonance light scattering (RLS) method for the determination of protein is reported. In the Tris–HCl (pH 7.50) buffer, protein enhanced the RLS intensity of the Y3+–2‐thenoyltrifluoroacetone (TTA)–sodium dodecyl sulphate (SLS) system. The enhanced RLS intensities were in proportion to the concentrations of proteins in the range 8.0 × 10?9–1.0 × 10?5 g/mL for BSA, 1.0 × 10–8–1.0 × 10?5 g/mL for HSA and 1.0 × 10–8–1.0 × 10?6 g/mL for EA, and their detection limits were 5.0, 5.4 and 6.7 ng/mL, respectively. Actual samples were satisfactorily determined. The interaction mechanism was also studied. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

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