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1.
Pesticide residues in air from coastal environment, south India.   总被引:4,自引:0,他引:4  
Chlorinated pollutants are transported through atmosphere. India is one of the point source countries for these pollutants [1]. In this study the concentration of DDT and HCH were evaluated in air from a tropical coastal environmental (at Parangipettai--southeast coast of India). DDT and HCH ranged in concentrations from 0.16 to 5.93 ng m-3 and 1.45 to 35.6 ng m-3 respectively. The ban on DDT in agriculture is reflected from the low residue levels recorded, predominantly by metabolites other than the parent compounds.  相似文献   

2.
Water samples collected from Vellar river and Pichavaran mangroves at Porto Novo (11 degrees 29' N, 79 degrees 46' E), Tamil Nadu State, South India, from December 1987 to January 1989 were analyzed to determine the seasonal variation of the levels of organochlorine insecticides such as HCH (BHC) and DDT. Both these insecticides showed higher levels from October to February, although this trend was more pronounced in HCH than DDT, reflecting the application of technical HCH largely and probably small quantities of DDT during the flowering season of rice. The alpha-HCH was detected as a dominant isomer for all seasons monitored followed by beta-HCH. Among DDT compounds, p,p'-DDT was the highest in river water except in the dry season when p,p'-DDD showed a higher percentage. On the other hand, in mangroves p,p'-DDE was highest during the wet season and p,p'-DDD during the dry season. Air-water partitioning data of HCH isomers and DDT compounds in Vellar river revealed that these chemicals tend to be in the water phase. These observations may aid in understanding the role of a tropical paddy area on the behavior and fate of man-made chemicals in view of worldwide contamination.  相似文献   

3.
Paddy soil and sediment samples collected from the Vellar River watershed, Tamil Nadu state, South India from December, 1987 to January, 1989 were analysed to understand the comprehensive behaviour of organochlorine insecticides (HCH and DDT) in the tropical environment. HCH (BHC) showed higher levels in soil during wet season, reflecting the application of technical HCH largely during the flowering season of rice. On the other hand, DDT residues were low and did not show a significant seasonal trend in soil or sediment, indicating small quantities of DDT utilized at present for agricultural purposes in India. When compared to soil, the residue levels in sediments are low and the seasonal variation is less pronounced. This indicates that in tropical watersheds, the relative flux of residues into the aquatic environment is smaller than the amount volatilized to the atmosphere.  相似文献   

4.
Air samples collected from Porto Novo (11 degrees 29' N, 79 degrees 46' E), Tamil Nadu State, South India from December, 1987 to January, 1989 were analysed to determine the seasonal variations of the levels of organochlorine insecticides such as HCH (BHC) and DDT. Both these insecticides showed higher levels from August to January, although this trend was more marked in HCH than DDT, reflecting the application of HCH largely, and probably small quantities of DDT during the flowering season of rice. The alpha-HCH was detected as a dominant isomer for all seasons monitored followed by gamma-HCH. Among DDT compounds, p,p'-DDT was the highest except in dry season (January to April) when p,p-DDE showed higher percentage. The levels and percentage composition of these insecticides recorded in the present study may aid in interpreting the role of a 'point source' area since India is one of the countries still using the persistent organochlorine pesticides in large quantities.  相似文献   

5.
Feng K  Yu BY  Ge DM  Wong MH  Wang XC  Cao ZH 《Chemosphere》2003,50(6):683-687
The use of organo-chlorine (DDT and HCH) has been banned in China for 20 years. A field survey was carried out during 1999-2000 in the Taihu Lake Region. Organo-chlorine pesticide (OCP) residues in soil, water, fish and sediment samples were investigated. DDT was detected in 5 out of 10 samples with concentration ranging from 0.3 to 5.3 microg/kg in the surface (0-15 cm) layer, 6 out of 10 with 0.5 to 4.0 microg/kg in the subsoil layer (16-30 cm), and 4 of 10 with 0 to 2.7 microg/ kg in the deep soil layer (31-50 cm). Results for HCH residues in soil samples were similar to those of DDT. These results indicate that OCP residues in 0-50 cm profile had been leached out or degraded to safe level. In river water DDT was detected in 10 out of 13 samples ranging from 0.2 to 9.3 microg/l, with an average of 1.0 microg/l. While HCH was detected in 12 out of 13 samples ranging from 0.02 to 36.1 microg/l, with an average 5.6 microg/l. DDT residues in sediment ranged from 0.1 to 8.8 microg/kg, while HCH ranged from 0.3 to 66.5 microg/kg. DDT residues in fish body ranged from 3.7 to 23.5 microg/kg and HCH ranged from 3.7 to 132 microg/kg. These results demonstrate an accumulation through food chain (from soil-water-sediment-microbes-crop-fish-... etc.), also that HCH residues are generally more persistent than DDT residues. However, all these data are well below than the state warning standard limit.  相似文献   

6.
Maule AG  Gannam AL  Davis JW 《Chemosphere》2007,67(7):1308-1315
Recent studies have demonstrated that fish feeds contain significant concentrations of contaminants, many of which can bioaccumulate and bioconcentrate in fish. Organochlorine (OC) contaminants are present in the fish oils and fish meals used in feed manufacture, and some researchers speculate that all fish feeds contain measurable levels of some contaminants. To determine the concentration of contaminants in feeds used in US Fish and Wildlife Service's National Fish Hatcheries, we systematically collected samples of feed from 11 cold-water fish hatcheries. All samples (collected from October 2001 to October 2003) contained at least one polychlorinated dibenzo-p-dioxin (PCDD), polychlorinated dibenzofuran (PCDF), polychlorinated biphenyl (PCB) congener, or dichlorodiphenyltrichloroethane (DDT) metabolite. Of the 55 samples in which they were analyzed 39 contained PCDDs, 24 contained PCDFs and 24 contained DDT or its metabolites. There were 10- to 150-fold differences in concentrations of total PCBs, PCDDs, PCDFs and DDT. Although PCBs were the most commonly detected contaminant in our study, concentrations (range: 0.07-10.46 ng g(-1) wet weight) were low compared to those reported previously. In general, we also found lower levels of OCs than reported previously in fish feed. Perhaps most notable was the near absence of OC pesticides - except for DDT or its metabolites, and two samples containing hexachlorocyclohexane (HCH). While contaminant concentrations were generally low, the ecological impacts can not be determined without a measure of the bioaccumulation of these compounds in the fish and the fate of these compounds after the fish are released.  相似文献   

7.
Chlorinated compounds have preferential attraction for organic phases found in sediments. Usage of chlorinated pesticides in agriculture and vector control is more in developing countries. The residue levels of HCH isomers, and DDT, and its metabolites were quantified in surface sediments from the River kaveri and Coleroon in Tamil Nadu state, South India. The concentration of HCH ranged from 4.35 to 158.4 ng g-1 (dry wt.). Among the isomers of HCH, alpha-HCH is predominant followed by beta and gamma-HCH. The levels of DDT varied from 0.69 to 4.85 ng g-1 (dry wt.). Among the DDT compounds, p,p'-DDE quantified more (> 40%) in all the sites. This suggests that p,p'-DDE is a major breakdown (dehydrochlorination) product of DDT in the sediment compartment. Higher concentration of HCH residues reveals its large usage in agriculture. The flux of pesticide residues from land to river including downward flux to sediment is less.  相似文献   

8.
Mishra K  Sharma RC  Kumar S 《Chemosphere》2011,85(3):454-464
Organochlorine pesticides (OCPs) have been beneficial to man and environment but their inadvertent use has caused considerable harm to human health. Despite the proliferation of different types of pesticides, organochlorines such as HCH and DDT still account for two third of the total consumption in India because of their low cost and versatility in action again various pests. Since, Assam, a state in North-eastern part of India is an endemic area with perennial transmission where mosquito borne diseases are serious health problems; these pesticides are still being used in huge quantities in vector control as well as in agriculture. A total of 331 human blood samples were collected from district Nagaon and Dibrugarh of Assam to determine the residue levels of DDT and HCH in human blood. The concentrations of selected persistent organochlorine pollutants were measured with gas chromatography-electron capture detector. The results demonstrated that the mean levels of total DDT and HCH were 743 μg L(-1) and 627 μg L(-1) for district Nagaon while 417 μg L(-1) and 348 μg L(-1) for district Dibrugarh. The difference of total HCH and total DDT between these two districts was found to be highly significant (P<0.0001). Among DDT metabolites, the same trend was observed for both the districts as p,p-DDT was the principal component contributed 41% for Nagaon and 58% for Dibrugarh. In case of HCH residues, for Nagaon, β-HCH was the predominant contaminant comprised more than 34% while for Dibrugarh, it was α-HCH that was contributing 43% of total HCH concentration.  相似文献   

9.
Concentrations of polychlorinated biphenyls (PCBs), DDT and its metabolites (DDTs), HCH isomers (HCHs), chlordane compounds (CHLs) and hexachlorobenzene (HCB) were determined in sediment, soil, whole body homogenates of resident and migratory birds and their prey items (including fish, green mussel, snail, earthworm, crabs, prawn, lizard and frogs), bird eggs and bats collected from southern India during 1995 and 1998. Accumulation pattern of organochlorines (OCs) in biota was, in general, in the order, HCHs > DDTs > PCBs > CHLs = HCB. Magnitude of OC concentrations increased in the order of sediments < green mussel < earthworm < from < lizard < fish < bird egg < bats < birds tissues. Biomagnification features of OCs were examined in resident and migrant birds to evaluate the exposure levels of these chemicals in wintering grounds of migrant birds. Accumulation of DDTs in migratory birds during wintering in India may be of concern due to the great biomagnification potential of DDTs. Eggs of some resident species contained noticeable concentrations of OCs. Concentrations of OCs in three species of bats analyzed in this study were lower than that found in passerine birds. In addition to OCs, butyltin compounds were also detected at low concentrations in bats.  相似文献   

10.
Abstract

This study aims to establish the relationship between the consumption of certain foods and the presence of organochlorine pesticides in human milk. A total of 167 samples of breastmilk were collected. Sample analysis was carried out by gas chromatography with electron capture detector. Pesticide concentrations (op’DDT, pp’DDT, pp’DDE, Σ-DDT, HCB, β-HCH) were grouped by consumption level of fish, dairy products, meat, eggs, and seafood and then were compared to each other. The odds ratio (OR) was calculated between the concentration of pesticides (higher and/or lower than median) and the exposure variable (high consumption). The results indicated low median concentrations of HCB, β???HCH, op’DDT and pp’DDT, whose fluctuations and trends between different frequencies of food consumption were not significant. pp’DDE and Σ???DDT values according to the increase in consumption of fish were significantly increased. Women with high fish consumption have a higher risk of high concentrations of pp’DDE and Σ-DDT (OR: high consumption: 5.6 (1.3–23.6). A protective effect was observed in the consumption of dairy products (β-HCH and op’DDT), meat (HCB), and seafood (pp’DDT). These results suggest that it is possible that the consumption of fish, dairy products, meat, and seafood influences the presence of organochlorine pesticides in the studied population.  相似文献   

11.
This study examined residual concentrations and associated ecological risks of the organochlorine pesticides (OCPs) hexa- chlorocyclohexane (HCH) and dichloro-diphenyl-trichloroethane (DDT) in water, sediment, and fish of the Songhua River in Zhaoyuan County, China. In June 2012, 10 water, 10 sediment, and 20 fish samples were collected. Residual concentrations of ΣHCH and ΣDDT ranged from 10.0–35.59 ng L?1 (mean 28.03 ± 11.66 ng L?1) and 5.12–39.66 ng L?1 (mean 32.36 ± 11.58 ng L?1) for water. Residual concentrations of ΣHCH and ΣDDT ranged from 0.52–3.00 ng g?1 (mean 2.04 ± 0.73 ng g?1) and 0.34–3.41 ng g?1 (mean 2.38 ± 0.92 ng g?1) for sediment. The ratios of α-HCH/γ-HCH were close to 1 at the majority of sampling points, indicating considerable new pollution from the use of lindane. The ratios of p,p′-DDE + p,p′-DDD/ΣDDT were less than 0.5, indicating recent inputs from DDT impurities in dicofol. All HCH and DDT isomers except for p,p′-DDD were detected in fish tissue samples, but the associated ecological risks were estimated to be below levels of concern. The study revealed a historical usage of OCPs in the Zhaoyuan section of the Songhua River and new OCP from the use of lindane and dicofol.  相似文献   

12.
An Indian sandy loam soil was initially treated with 1 kg a.i. ha(-1) of either [(14)C]-p,p'-DDT or [(14)C]-gamma-HCH during winter. DDT concentration after 30 days declined to 75.3%, which included 2.1% soil-bound residues. After 150 days, DDT levels further decreased to 42.4% with a concomitant increase in bound residues amounting to 5.9%. Identical treatment with HCH caused the residue levels to be reduced to 67.4 and 23.6%, after 30 and 150 days, respectively. During this period, the soil-bound residues of HCH increased from 5.2 to 12.8%. Repeat application to pre-treated soils in summer and subsequent field exposure for 30 days reduced the concentration of DDT to 52.1% and that of HCH to 42.4% of the total concentration following the second treatment. In parallel control experiments, which received only a single treatment, DDT levels declined to 61.3%, while HCH slumped to 45.3%, indicating a slower dissipation rate than in the corresponding repeated treatments. In repeat experiments, the soil-bound residues of DDT and HCH showed only a 1.07 to 1.08-fold increase in 30 days, as compared to three to ten-times increase in the control experiments. The results amply demonstrate that pre-treatment of tropical soils with DDT or HCH enhances their rate of dissipation and significantly reduce the formation of their soil-bound residues.  相似文献   

13.
Abstract

This research is a case study on detection of pesticides in river water, sediment as well as fish samples from Tapi River, among the major rivers of Gujarat, India. To investigate the misuse, concentration level and occurrence patterns of persistent pesticides, samples were collected from the river. Chlorpyrifos, methyl parathion, hexachlorocyclohexane (HCH), dichloro diphenyl trichloroethane (DDT) and endosulfan were analyzed by gas chromatography technique with flame ionization detector (FID). Scanty reports are available, but after 1999, no such data are reported as some of these pesticides have been banned. Although these pesticides are still in use which we observed from the obtained results. In this river, the amount of endosulfan, chlorpyrifos, and methyl parathion was observed in surface water with concentrations of 37.56?µg/L, 0.86?µg/L and 0.43?µg/L, respectively. Endosulfan, DDT and methyl parathion detected in sediment were 38.38?ng/g, 0.65?ng/g and 0.77?ng/g, respectively. In fish samples, levels of endosulfan, chlorpyrifos, and methyl parathion detected were 101.28, 0.392, and 3.49?ng/g correspondingly. Results showed that highly toxic pesticides are still being used in the surrounding area, and there is an urgent need for enforcement of rules to control the production and application of such pesticides.  相似文献   

14.
Fifty fish samples were collected from the Pearl River estuary (PRE) and Daya Bay, South China and were analyzed for DDTs, HCHs, chlordanes and polybrominated biphenyl ethers (PBDEs). Except the high concentrations of DDT observed in fishes, the concentrations of HCHs, chlordanes and PBDEs were low when compared to other regions. BDE-47 was the predominant PBDE congener and the BDE-209 concentrations were relatively low, despite its high concentration in surface sediments. The absence of significant increase of DDT, HCH, chlordane and PBDE concentrations towards higher delta15N values, as well as the lack of a significant correlation (p<0.1) between log concentrations (lipid normalized) and delta15N, may indicate a weak biomagnification of these chemicals in the food webs. Good agreement was observed between their concentrations and lipid contents of the organisms. Bioconcentration was suggested to be responsible for the accumulation of OCPs and PBDEs in the lower trophic organisms in the studied subtropical waters.  相似文献   

15.
Marco JA  Kishimba MA 《Chemosphere》2006,64(4):542-548
Leaves of Eucalyptus sp., Prunus domestica (plum), and Anacardium occidentale (cashew), as well as roots and leaves of Manihot esculenta (cassava) were used to study the local distribution of pesticides and metabolites from a point source, an old storage site at Vikuge farm in Tanzania. The GPC-cleaned extracts were analyzed by GC-ECD and GC/MS. Eleven organochlorine pesticide residues namely pentachloroanisole, p,p'-DDT, o,p'-DDT, p,p'-DDE, o,p'-DDE, p,p'-DDD, o,p'-DDD, alpha-HCH, beta-HCH, delta-HCH and epsilon-HCH were detected in the samples. The concentrations of total DDT were 818 ng/g fw in Eucalyptus sp., 16 ng/g fw in A. occidentale and 4 ng/g fw in P. domestica. In M. esculenta, total DDT ranged from 191 to 586 ng/g fw in roots and 7 to 425 ng/g fw in leaves. The concentrations of total HCH were up to 15 ng/g fw in Eucalyptus sp., while the concentrations of pentachloroanisole were up to 2 ng/g fw in leaves of M. esculenta. There are very strong positive correlations in the concentrations of the detected compounds, suggesting that they have a common source. The low DDE/DDT ratios (0.02-0.07) in all samples indicate input of non-degraded DDT from the source. The high alpha-HCH/gamma-HCH ratios in some samples (>3.1-10) indicate input of technical HCH. The concentrations of total DDT in cassava roots were either very close to, or greater than, the FAO/WHO limit, indicating risks and concern to public health.  相似文献   

16.
The contribution of spraying DDT and HCH for malaria control towards the contamination of bovine milk was investigated by analysing milk samples collected from preselected localities sprayed with either DDT or HCH in the Punjab. A direct correlation was found between the amounts of residues of these insecticides in milk and their typical usage pattern for the mosquito control programme. It is considered that these results may have significant bearing on the regulatory control of DDT and HCH residues in milk.  相似文献   

17.
Human milk samples collected from areas having intensive cotton cultivation and sparse cotton cultivation in Punjab (India) were analysed for organochlorine insecticides. Both DDT and HCH were detected in almost all the samples analysed. The average levels of Sigma-DDT and Sigma-HCH residues in samples from cotton-growing areas were significantly higher than in those from areas where cotton is sparsely grown. Residues of Sigma-DDT mainly comprised p,p'-DDT and p,p'-DDE, while those of Sigma-HCH residues were mainly in the form of its beta-isomer. Median values of 0.52 microg g(-1) of Sigma-DDT and 0.19 microg g(-1) of Sigma-HCH in samples of human milk from cotton-growing areas of Punjab (India) were higher than those reported from most other countries in the World.  相似文献   

18.
Ringed seal (Phoca hispida) and bearded seal (Erignathus barbatus) are the main prey of polar bears (Ursus maritimus), and information on organochlorines (OCs) in these pinniped species is important to understand the transport, fate and effects of persistent organic pollutants in the Arctic ecosystem. Thus, OCs were analysed in blood samples of bearded and ringed seals from the coastal ecosystem of the north-western Svalbard archipelago (Kongsfjorden, 78.55degrees N). The relative contribution of OCs could be ranked as follows: Ringed seal females: sigmaPCB > sigma DDT > sigma CHL > sigma HCH > HCB > Mirex. Ringed seal males: sigma PCB > or = sigma DDT > sigma CHL > sigma HCH > or = HCB > Mirex. Bearded seal females: sigma PCB > sigma HCH > or = sigma CHL > sigma DDT > Mirex > HCB. Bearded seal males: sigma PCB > sigma DDT > or = sigma CHL > sigma HCH > Mirex > or = HCB. The concentrations of sigmaPCB and sigma DDT were higher in ringed seals than in bearded seals, whereas sigma HCH was higher in bearded than in ringed seals. In ringed seal females and males sigma PCB was 337 +/- 95 ng/g (n= 6) and 625 +/- 443 ng/g (n=6), whereas sigma DDT was 165 +/- 47 ng/g (n=6) and 621 +/- 559 ng/g (n = 6), respectively. In bearded seal females and males, sigmaPCB was 159 +/- 132 ng/g (n = 6) and 248 +/- 93 ng/g (n = 5), whereas sigmaDDT was 46 +/- 41 ng/g (n = 6) and 161 +/- 71 ng/g (n = 5), respectively. The inter-species differences are caused by a higher trophic position of ringed seals in the Svalbard ecosystem compared to bearded seals. OC levels in ringed seals at Svalbard are similar to those reported from the North-American Arctic and in the lower range compared to previously reported data from Svalbard.  相似文献   

19.
As part of a large study on assessing the impact of environmental contaminants in Indian avifauna, the presence of organochlorine pesticides (OCPs) in liver tissues of 16 species of birds collected from Ahmedabad, India during 2005–2007 was quantified. The higher concentrations of total organochlorine pesticides were detected in livers of shikra Accipiter badius (3.43?±?0.99 μg/g wet wt) and the lower levels in white ibis Pseudibis papillosa (0.02?±?0.01 μg/g wet wt). Marked differences in the concentrations of total OCPs occurred among species (p?<?0.05). Concentrations of DDT and its metabolites, hexachlorocyclohexane (HCH) and isomers, dieldrin, and heptachlor epoxide were lower than the concentrations reported for various species of birds in India. Accumulation pattern of organochlorine pesticides in birds was, in general, in the order HCH > DDT > heptachlor epoxide > dieldrin. Among various pesticides analyzed, p,p′-DDE and β-HCH contributed maximum towards the total OCPs and study indicates the continuous use of lindane and DDT for agriculture and public health purpose, respectively. Although no serious threat is posed by any of the organochlorine pesticides detected in the present study species, continued monitoring is recommended.  相似文献   

20.
High volume air samples for organochlorine (OC) pesticides, polychlorinated biphenyls (PCB) and polycyclic aromatic hydrocarbons (PAH) were collected during August-September 1989 in Brazzaville, Congo (4.14 degrees S, 15.14 degrees E). Average concentrations (ng/m3) were SigmaDDT=2.8; Sigma HCH (hexachlorocyclohexane)=0.42; Sigmachlordane=0.027; SigmaPCB=0.55 Sigma3-6 ring PAH=42; total DDT concentrations in Brazzaville fell between those reported in Porto Novo and Delhi (India) and were 20-100 times higher than those found in US cities. The average gamma-HCH to alpha-HCH ratio (11) indicated use of lindane instead of technical HCH. The similarities between chlordane levels in Brazzaville and the open ocean indicated that little or no local use occurs. PAH levels were about equal to or lower than those reported in US cities, whereas PCB levels were three times lower. Vapor/particle distribution coefficients for several OC and PAH were in good correlation with their vapor pressures. The fraction of PAH on particles was greater than that of OC pesticides.  相似文献   

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