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1.
This study reports the levels and distribution patterns of some organochlorine pesticides (OCPs) in fish samples of the Gomti river, India, collected from three sites. In the fish muscles ∑OCPs ranged between 2.58–22.56 ng g−1 (mean value: 9.66 ± 5.60 ng g−1). Neither spatial nor temporal trends could be observed in distribution of the OCPs. Aldrin was the predominant OCP, whereas, HCB and methoxychlor could not be detected. α-HCH and β-HCH among the isomers of HCH and pp-DDE among the metabolites of DDT were the most frequently detected OCPs. The results revealed that the fish of the Gomti river are contaminated with various OCPs.  相似文献   

2.
Residues of hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) and their environmental risks in surface sediments collected from the rivers and lakes in Yangtze River Catchment of Wuhan, China, are investigated in this paper. Based on dry weight (dw), the concentrations of ΣHCH (α-, β-, and γ-HCH) and ΣDDT (p p′-DDT, o p′-DDT, p p′-DDE, p p′-DDD) in sediments ranged from 0.10 to 21.10 ng g−1 (mean, 4.03 ng g−1 dw) and 0.79 to 35.61 ng g−1 dw (average, 6.93 ng g−1 dw), respectively. Compared with some published guideline values of organochlorine pesticides (OCPs) in sediments, the concentrations of HCHs were at safe levels while the DDT residues would pose adverse biological effects in this studied catchment. The distribution of OCPs in sediments indicated that the input of tributaries was an important factor for OCP residues in the mainstream of the Yangtze River. Levels of OCPs in the sediments were influenced by total organic carbon contents, clay contents, water contents, and pH values of sediments. The present study suggested that historical usage of technical HCH and DDT was the main reason for OCP residues in the sediments from both rivers and lakes. Furthermore, the composition of OCPs reflected additional sources of the holding usage of lindane and fresh inputs of dicofol mixture in this region.  相似文献   

3.
This study reports the levels and distribution patterns of selected polycyclic aromatic hydrocarbons (PAHs) in fish samples of the Gomti river, India, collected from three sites during the pre- and post-monsoon seasons of the years 2004–2005. In the fish muscles, ∑PAHs ranged between 12.85 and 34.89 ng g−1 wet wt (mean value: 23.98 ± 6.70 ng g−1). Naphthalene was the most prevalent compound both in terms of detection as well as levels, while, benzo[k]fluoranthene, benzo(a)pyrene, and indeno(123-cd)pyrene + benzo(ghi)perylene could not be detected in any of the sample. Low-molecular weight PAHs were observed dominating over the high molecular weight PAHs.  相似文献   

4.
An evaluation of selected organochlorine pesticide residues [p,p′- dichlorodiphenyltrichloroethane (DDT), p,p′- dichlorodiphenyldichloroethylene (DDE), p,p′- dichlorodiphenyldichloroethane (DDD), α, β, γ and δ- hexachlorocyclohexane (HCH)] in the surface soils of Hanoi, Vietnam was carried out. Sixty representative soil samples were collected from the centre of Hanoi and five surrounding districts. In agricultural areas, ΣDDT concentrations ranged from < 0.02 to 171.83 ng g−1 (mean 89.86 ng g−1) dry weight, whereas ΣHCH concentrations ranged from < 0.05 to 20.57 ng g−1 (mean 8.03 ng g−1) dry weight. Investigation of the ratio of different isomers in the soil samples indicates that there has been no recent input of DDT and HCH in the study area.  相似文献   

5.
The distribution of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) was investigated in Mediterranean blue mussel collected at four locations in Mali Ston Bay few times a year in 2005–2007. OCPs were found in all samples and levels ranged between 0.07 and 7.58 ng g−1 dry wt. Levels of PCBs ranged between 0 (below detection limit) and 21.55 ng g−1 dry wt. For most analyzed compounds there were no significant level changes between the 3 years. Exceptions are decreased levels of β-HCH, DDD, and PCB-138 and increased levels of γ-HCH and DDT in 2007. However, mussels from this area are applicable for human diet.  相似文献   

6.
On a global scale tropical regions in developing countries are thought to be significant source areas of organochlorine pesticides (OCPs), owing to a long history of widespread use and only a recent production ban or restriction on the application of these pesticides. In the present study, 32 soil samples were collected in 2004 from agriculture lands around the urban area of Guangzhou, in southern China, and analyzed for residues of OCPs including p,p’-DDT, p,p’-DDE, p,p’-DDD, and α-, β-, γ-, and δ-HCH. The dry weight concentrations of ΣHCH (ΣHCH = α-HCH + β-HCH + γ-HCH + δ-HCH) ranged from 0.2 to 103.9 ng/g, with a median of 4.4 ng/g. Residues of ΣDDT (ΣDDT = p,p’-DDT + p,p’-DDE + p,p’-DDD) ranged from 7.6 to 662.9 ng/g, with a median of 67.3 ng/g. The predominance of β-HCH among HCHs in most soil samples suggested that they were from historical contamination rather than recent input. The mean HCH α/γ-ratio of 2.72 was lower than that of technical HCHs, possibly due to more loss of α-HCH via evaporation from soil with time, conversion of γ-HCH to α-HCH or recent application of lindane in the region. The mean ratio of (DDE + DDD)/ΣDDT was 0.54, indicating that quite a portion of DDT in soils was degraded since its official ban in 1983. Higher DDT concentrations with lower (DDE + DDD)/ΣDDT ratios at a few sites suggested possible local DDT sources via the application of Dicofol. A positive but weak correlation (r = 0.449, p < 0.01) between DDT residues and TOC contents implied that soil organic matter might enhance adsorption of DDT in soils in the tropical regions. Hierarchical cluster analysis and principal component analysis were also performed to study the distribution and compositional patterns of OCPs as well as their sources and environemtal fates within the study area.  相似文献   

7.
Selected organochlorine pesticides (p,p′-DDT, p,p′-DDE, p,p′-DDD, α,β,γ,δ-HCH) were analyzed in the surface soils of Bacninh, Viet Nam. Forty representative soil samples were collected from Bacninh town and three surrounding districts. ΣDDT concentrations ranged from <0.02 to 160.86 ng g−1 dry weight, whereas ΣHCH concentrations ranged from <0.05 to 9.54 ng g−1 dry weight. The half-life times of ΣDDT and ΣHCH are 6.7 and 4.9 years, respectively. The decreasing trends of ΣDDT and ΣHCH levels during the period from 1992 to 2006 are observed. There is no recent input of DDT and HCH in the study area.  相似文献   

8.
This study investigated the occurrence of 16 polycyclic aromatic hydrocarbons (PAHs) and 6 phthalic acid esters (PAEs) in 11 vegetable species collected from nine farms of the Pearl River Delta, South China. Twelve PAH compounds and all PAE compounds were detected by gas chromatography coupled with mass spectrometry (GC-MS) in vegetables. The total concentrations of PAHs (ΣPAHs) and PAEs (ΣPAEs) ranged from 7.0 to 5353 μg kg−1 dry weight (d.w.), with a mean value of 1173 μg kg−1 d.w., and from 0.073 to 11.2 mg kg−1 d.w., with a mean value of 3.2 mg kg−1 (d.w.), respectively. The highest levels of ΣPAHs and ΣPAEs were found in Brassica juncea and Brassica parachinensis, respectively. For the same vegetable, the bioconcentration factors (BCFs; the ratio of contaminant concentration in plant tissue to the soil concentration) of PAHs (between 0.0037 and 5.5) are generally higher than those of PAEs (between <0.0001 and 0.61). It was also noted that there were great variations of organic contaminant levels, BCFs, and benzo[a]pyrene equivalent concentrations, which depend on the various contaminants, sampling locations, and vegetable species. The occurrences of PAHs and PAEs in this study are compared with those in other studies and their sources are discussed. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

9.
Concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were measured in 26 types of seafood commonly consumed by the general Korean population. The concentrations of total and carcinogenic PAHs ranged from 12.3 to 243 ng/g dry weight and from 0.21 to 18.4 ng/g dry weight, respectively, similar to those reported in other countries. The lower-molecular–weight aromatics, such as naphthalene, phenanthrene, and fluorine, predominated in the seafood samples. Estimated intakes of PAHs by seafood consumption for the general population, for men, and for women were 15.3, 16.7, and 13.8 ng/kg body weight/d, respectively. Squid, mackerel, and yellow croaker contributed to the highest intakes of PAHs. Among the 8 age groups investigated, children age <2 years and 3 to 6 years had high intakes of PAHs compared with adult groups. Dioxin toxic equivalents (TEQs) of PAHs were calculated using a TEQ proposed in the literature, and the intake was estimated to be 0.91 pg TEQ/kg body weight/d, which indicates that PAHs contributed the most (43%) to total TEQ intake. The estimated excess cancer risk values from seafood consumption for the general population (2.85 × 10−6), for men (2.93 × 10−6), and for women (2.68 × 10−6) slightly exceeded the guideline value (1.0 × 10−6) for potential cancer risk.  相似文献   

10.
Concentrations and profiles of polycyclic aromatic hydrocarbons (PAHs) were determined in thirty dust samples collected from kitchens that use wood cook system (WCS), kerosene stove cook system (KSCS) and butane gas cook system (BGCS). The total PAHs concentrations ranged from 52 to 497,  39 to 96 and 37 to 155 μg kg−1 for WCS, KSCS and BGCS respectively. The results indicate predominance of lower molecular weight (2–3 rings) over higher molecular weight PAHs and users of wood cook system are more exposed to higher levels of PAHs than the users of either kerosene cook system or butane gas cook system.  相似文献   

11.
This study reports concentration of polycyclic aromatic hydrocarbons (PAHs) in indoor air and dust samples collected from 24 homes in Kuwait. Mean ΣPAHs in indoor air ranged from 1.3 to 16 ng/m3 with a geometric mean of 5.6 ng/m3, whereas the dust concentrations varied over three orders of magnitude, from 3 to 2920 ng/g, with a geometric mean of 165 ng/g. The low-molecular-weight tricyclic and tetracyclic PAHs dominated the air profile constituting ∼70–90 % of the measured compounds, with phenanthrene (51%), fluorene (13 %), fluoranthere (8 %), and pyrene (7 %) being the major contributors. The PAH profile in dust was dominated by the high-molecular-weight PAHs, with three compounds (benzo[a]pyrene, benzo[k]fluoranthene, and benzo[b]fluoranthene) contributing ∼60% of the average ΣPAHs measured in the samples. Indoor-to-outdoor (I/O) ratios for individual compounds were <1 for the majority of compounds, suggesting that there were no significant indoor sources for these compounds in these homes. Using the measured concentrations in air and dust, together with estimates of inhalation and inadvertent dust ingestion rates for children and adults, estimated human nondietary exposure on a BaPequiv basis were 547 pg/kg body weight/day and 205 pg/kg body weight/day for children and adults, respectively. Exposure from dust ingestion contributes about 42% of nondietary intake of ΣPAHs in children, but only 11% for adults. The threefold difference in exposure estimates between children and adults in this study supports previous reports that children are at greater risk from pollutants that accumulate indoors.  相似文献   

12.
In this study, organochlorine pesticides (OCPs) and polychlorinated biphenyles (PCBs) levels were determined in 100 human milk samples from the city of Antalya. The levels of seven major PCB congeners; 28, 52, 101, 118, 138, 153, 180 and nine OCPs, α-HCH, β-HCH, γ-HCH, HCB, heptachlor epoxide, p.p-DDT, p,p-DDE, endosulfan-α and endosulfan-β were determined by gas chromatography with ECD detection. The levels of analyzed compounds were as follows: ΣPCBs 27.46 ± 11.58, ΣDDT 1,407 ± 123, and ΣBHC 160 ± 490 ng/g lipid wt.basis. PCB 153 and p,p-DDE were the dominant contaminants. The results have been discussed and compared with similar studies from other regions of Turkey.  相似文献   

13.
A total of 30 sediments, overlying water and porewater samples were collected from Lake Taihu, China for the analysis of PAHs. The total PAHs varied from 209 to 3,843 ng g−1 in sediments, from 238 to 7,422 ng L−1 in overlying water and from 2,012 to 19,899 ng L−1 in porewater, respectively. There are good correlations between sediment-porewater/sediment-overlying water partition coefficients and PAHs’ logKow values, with correlation coefficient of 0.94 and 0.95, respectively. The sediment PAHs in Lake Taihu originated from both pyrolytic and petrogenic sources, showing a mixed input pattern. Based on the numerical effect-based sediment quality guidelines of the United States, the sediments from Lake Taihu causing adverse effects by PAHs should have potential biological impact, but should have no impairment.  相似文献   

14.
Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in human milk from Chelem, Yucatan, Mexico were analyzed. Relatively high levels of p,p′-DDE, γ-chlordane, β-hexacyclohexane (β-HCH) and PCB congeners 170, 28, and 44 were found. Concentration profiles by OCP groups followed the next order: ΣDDTs > ΣChlordanes > ΣHCHs > ΣChlorobenzenes > ΣDrins. Total OCPs showed a decreasing tendency with number of births (primipara and multipara and age ranks) but these differences were not significant. ΣDDT levels were lower than in other studies in Mexico, but 36% of the samples exceeded the JMPR-FAO/WHO acceptable daily intake (ADI). About 60.53% of samples exceeded the ADI value for heptachlors.  相似文献   

15.
Levels of organochlorine pesticides (OCPs), including ΣDDTs, γ-HCH, HCB, aldrin, isodrin, trans-nonachlor, heptachlor and dieldrin, were determined in the razor clam, Ensis siliqua, collected monthly from February 2003 to April 2004 from the Islas Cíes in Ría de Vigo (Galicia, Spain). The sum of DDTs ranged from 2.17 to 26.9 ng g−1 dry weight (dw). Principal component analysis showed seasonal trends in the levels of some OCPs (γ-HCH and dieldrin). Pearson correlations (p < 0.05) were observed between OCP levels and the biometric parameters of condition index and body lipids.  相似文献   

16.
Organochlorine pesticides (OCPs) concentrations in sediments and sediment trap fluxes of particulate organic carbon and OCPs were measured from October 2006 to May 2008 in the urban reach of Haihe River, Tianjin, China, in order to investigate vertical fluxes and accumulation of OCPs in sediments. The concentrations of OCPs in sediments (dry weight basis) were in the range of 2.08–10.07 ng/g (mean 4.70 ng/g) for HCHs (α-, β-, γ-, δ-HCH), 5.82–43.39 ng/g (mean 17.43 ng/g) for DDTs (p,p′-DDE, p,p′-DDD, o,p′-DDT, p,p′-DDT). Compared with data reported in Haihe River 2003, the levels of OCPs showed a significant decrease between 2003 and 2008. This is mainly attributed to significant decrease of production and usage of HCHs and DDTs and biodegradation of HCHs and DDTs in sediment. Concentrations of HCHs and DDTs in sediments were well correlated with sediment organic carbon contents. Concentrations of OCPs in settling particles (dry weight basis) ranged from 21.2 to 138.4 ng/g (mean 52.6 ng/g) for HCHs, 30.0–245.7 ng/g (mean 87.1 ng/g) for DDTs, which were 2.2–48.2-fold higher than those associated with sediments. β-HCH was the dominant HCH isomer in both sediments and settling particles. Among DDTs, p,p′-DDE was found to be dominant in sediments, while p,p′-DDT was the predominant form in settling particles. This suggests that further biodegradation of OCPs occurred during the course of sedimentation and burial. The annual sediment trap flux of OCPs in Haihe River in the urban area of Tianjin was 177–211 μg/m2 yr for HCHs and 213–341 μg/m2 yr for DDTs, respectively.  相似文献   

17.
We report concentrations of several classes of organochlorines (OCs) in the blubber of California sea lions (Zalophus californianus) from the Gulf of California. Summed OC levels measured in 34 wild-ranging animals were, in general, lower than those previously reported in sea lions from the eastern Pacific. The rank order of OCs was ΣDDTs (mean = 3400 ng g−1 lipid weight [lw]) > ΣPCBs (1400 ng g−1 lw) > ΣHCHs (50 ng g−1 lw) ≥ ΣCHLORs (46 ng g−1 lw). The most abundant OC measured was the DDT metabolite, p,p′-DDE. No significant differences in OC profiles were found between genders or rookeries. Although the mean concentrations of OCs measured in adult males and females were similar, only adult females had significantly higher (p < 0.05) mean blubber concentrations of ∑DDTs and ∑HCHs than pups.  相似文献   

18.
Polycyclic aromatic hydrocarbons (PAHs) were investigated in the surface soils from Dashiwei and Datuo Karst tiankengs, Guangxi Province, South China. Concentrations of total PAHs ranged from 16.93 ng g−1 to 190 ng g−1 with a mean of 58.29 ng g−1. In Dashiwei more PAHs were concentrated than in Datuo (mean 74.42 ng g−1 > 42.15 ng g−1). Dashiwei and Datuo accounted for the majority of all PAHs concentrated in the lower location through increased rates (58% and 37%) from the upper to lower geographical levels, respectively. Dashiwei presented the stronger trapping ability for heavier molecular weights on the tiankeng floor with a concentration increase rate of 167% when compared to that of the lighter molecular weights (which had a concentration increase of rate 6%), which was in contrast to the Datuo with a concentration increase rate of 37% for lighter molecular weights and 31% for heavier molecular weights. In Dashiwei, it was found that the ratio of heavier PAH compound molecular weight resulted in its higher precipitation recording on the tiankeng floor. The differentia between two tiankengs, therefore, are related to their environmental characteristics and the PAHs physiochemical properties. The analytical result from the PAHs indicators suggest that a petrogenic source was dominant in the area studied. Therefore, the karst tiankeng has the potential to act as a geophysical well for PAHs deposition, especially for the heavier molecular weighted PAH.  相似文献   

19.
Organochlorine (OC) bioaccumulation and biomagnification were studied in a marine food web at a pristine site in Iceland. The species studied were the gastropod and grazer chink shell (Lacuna vincta), the filter feeding bivalve blue mussel (Mytilus edulis), the predators butterfish (Pholis gunnellus), and the seabird black guillemot (Cepphus grylle), all sampled and analysed in 1996–1997. Individual OC levels were generally low in chink shell and blue mussels, somewhat elevated in the fish, and an order of a magnitude higher in the top predator black guillemot, except for ΣHCH (hexachlorocyclohexane isomers) and Σchlordane levels, which were similar in all organisms, ranging from 10 to 36 ng/g lipid weight (lw). In the molluscs and fish, mean concentrations of ΣPCB (polychlorinated biphenyl) ranged from 111 to 377 ng/g lw, ΣDDT (dichlorodiphenyltrichloroethane) ranged from 19 to 65 ng/g lw, and HCB (hexachlorobenzene) ranged from 21 to 30 ng/g lw. The levels of same OCs in the black guillemot were on average 2352, 361, and 283 ng/g lw, respectively. The OC tissue concentrations in blue mussel and black guillemot are comparable to levels in Arctic and sub-Arctic regions, but OC levels in blue mussel tissue were an order of magnitude lower than found in the North Sea and the Baltic Sea. The relative composition of OCs were generally similar among species with the PCB congeners emerging as the most abundant compounds with levels an order of magnitude higher than the other compounds in all species. Food web magnification factors (FWMFs) were determined for the OCs by using trophic levels determined from δ15N. FWMFs >1, indicating biomagnification, were found for ΣPCB, penta- or higher chlorinated PCBs (e.g., PCB 101, 118, 138, 153, 180), β-HCH, HCB, ΣDDT, p,p-DDE, and transnonachlor. The highest FWMF was observed for PCB 180 at FWMF = 5.8.  相似文献   

20.
Levels of 16 organochlorine pesticides (OCPs) were investigated in 39 composite samples of agricultural crops, related by-products, and foodstuffs collected in Vojvodina, Serbia, in 2002 through 2004. After extraction and cleanup, OCPs were determined by capillary gas chromatography using electron-capture detection. The highest mean level of 0.971 ng/g whole weight (ww) was found for α-HCH in wheat flour samples. OCPs levels were well lower than the respective maximum residue limits set by current European and Serbian regulations. Mean OCP levels were low (<1 ng/g ww) for all sample types. The most frequently determined residue was 4,4′-DDT (identified in 76.9% of all samples analyzed), followed by γ-HCH (66.7%), β-HCH (48.7%), and endosulfan II (41.0%). OCP levels were compared with data from other international surveys. Calculated daily intakes of OCPs by way of consumption of the crop products included in this study according to data of the Serbian National Institute for Statistics were compared with the acceptable daily intakes established by the Food and Agriculture Organization/World Health Organization. The average level of contamination of the Vojvodina diet was believed to be harmless regarding the studied food commodities.  相似文献   

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