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1.
Green mussel (Perna viridis) and water samples were collected from Ennore creek, Chennai by seasonal sampling and analyzed for organochlorine pesticide residues (OCPs) like dichloro-diphenyl-trichloroethane (DDT) and its metabolites, isomers of hexachlorocyclohexane (HCH) and endosulfan. These residues were analyzed by using gas chromatograph (GC) with μECD. In the present study, mussel samples showed very low concentrations of OCPs in the statistical order of DDT (5.83 ng g???1 wet tissue) > endosulfan (2.84 ng g???1 wet tissue) > HCH (2.34 ng g???1 wet tissue). Concentrations of OCPs in water samples were in the statistical order of endosulfan (29.21 ng L???1)?> HCH (17.14 ng L???1)?> DDT (14.63 ng L???1). To our knowledge, this is the first report on the seasonal variation of OCPs and especially the quantification of endosulfan in Ennore Creek. The present study recommends that continuous monitoring in Ennore creek is necessary to assess possible impact on human health.  相似文献   

2.
Sediments used in this study were selected from 23 stations in the middle and lower reaches of the Yellow River and its tributaries in November 2005. The levels and distribution patterns of selected organochlorine pesticides (OCPs = p,p -DDT, o,p -DDT, p,p -DDE, p,p -DDD, α-, β-, γ-, and δ-HCH) in samples were investigated by analysis of gas chromatography coupled with micro-electronic capture detector. Concentration of OCPs in the sediments from the Yellow River ranged from 0.05 to 5.03 ng g???1 (mean, 1.02 ng g???1) for ∑DDT, 0.09–12.89 ng g???1 (mean, 1.08 ng g???1) for ∑HCH. The concentration distribution of ∑DDT and ∑HCH varied significantly with different sampling station, indicating their different contamination sources. Composition analyses demonstrated that residues of DDTs in sediments came from the previous inputs of organochlorine pesticides, while β-HCH and γ-HCH significantly dominated in the sediments for HCHs.  相似文献   

3.
To evaluate the contamination of organochlorine pesticides (OCPs) in marine organisms and their potential health risk on consumers in the northern Yellow Sea of China, mollusks, wild shrimps, and crabs were collected from the Yantai coast, and the OCP contents in the samples were analyzed and compared. The results indicate that all the samples have been contaminated by OCPs, and OCP concentrations varied in individual species and in sampling sites. Among the studied OCPs, ∑HCH and ∑DDT concentrations ranged from 0.91 to 13.92 ng g?1 and from 10.16 to 411.19 ng g?1, respectively. Meretrix was highly enriched with HCHs, while the highest DDT concentration was found in Crassostrea. For the OCP isomers, β-HCH was the predominant isomer of HCHs, and p,p′-DDE concentration was much higher than other isomers of DDTs. The concentrations of other OCPs (HCB, t-CHL, endrin, and mirex) were relatively low. For the shrimp and crab samples, Alpheus distinguendus samples accumulated a higher level of HCHs but lower DDTs than Oratosquilla aratoria and Carcinoplax vestitus in all sampling areas. HCHs in the samples of contrast area were not significantly lower than that of the sewage outfall area and port area, whereas DDTs in the samples of contrast area were relatively lower than that of the other two areas. Generally, all the OCP contents in the samples are in the range of the edible hygienic criteria except the total concentration of DDTs in Crassostrea.  相似文献   

4.
The study was conducted on 20 vegetables including leafy, root, modified stem, and fruity vegetables like bitter gourd, jack fruit, french-bean, onion, colocassia, pointed gourd, capsicum, spinach, potato, fenugreek seeds, carrot, radish, cucumber, beetroot, brinjal, cauliflower, cabbage, tomato, okra, and bottle gourd. Forty-eight pesticides including 13 organochlorines (OCs), 17 organophosphates (OPs), 10 synthetic pyrethriods (SPs), and eight herbicides (H) pesticides were analyzed. A total number of 60 samples, each in triplicates, were analyzed using Quick, Easy, Cheap, Effective, Rugged, and Safe method. The quantification was done by GC-ECD/NPD. The recovery varies from 70.22% to 96.32% with relative standard deviation (RSD) of 15%. However the limit of detection ranged from 0.001?C0.009 mg kg???1 for OCs, SPs, OPs, and H, respectively. Twenty-three pesticides were detected from total 48 analyzed pesticides in the samples with the range of 0.005?C12.35 mg kg???1. The detected pesticides were: ??-HCH, Dicofol, ??-Endosulfan, Fenpropathrin, Permethrin-II, ??-cyfluthrin-II, Fenvalerate-I, Dichlorvos, Dimethoate, Diazinon, Malathion, Chlorofenvinfos, Anilophos, and Dimethachlor. In some vegetables like radish, cucumber, cauliflower, cabbage, and okra, the detected pesticides (??-HCH, Permethrin-II, Dichlorvos, and Chlorofenvinfos) were above maximum residues limit (MRL) (PFA 1954). However, in other vegetables the level of pesticide residues was either below detection limit or MRL.  相似文献   

5.
In order to characterize environmental vanadium distribution, mobility, and bioaccumulation, a total of 55 soil samples and 36 plant samples were collected in four typical land-use districts in Panzhihua region, Southwestern China. Soil samples were analyzed with the modified Community Bureau of Reference (BCR) sequential extraction procedure, and the content of vanadium in soil and plant was determined by ICP-AES. The total content of vanadium was 208.1?C938.4 mg kg???1 in smelting area, 111.6?C591.2 mg kg???1 in mining area, 94.0?C183.6 mg kg???1 in urban park, and 71.7?C227.2 mg kg???1 in agricultural area, respectively, while the bio-available content of vanadium was characterized that the polluted areas (mining area 18.8?C83.6 mg kg???1, smelting area 41.7?C132.1 mg kg???1) and the unpolluted area (agricultural area 9.8?C26.4 mg kg???1, urban park 9.9?C25.2 mg kg???1). In addition, the contamination degree of vanadium in soil was smelting area > mining area > agricultural area ?? urban park. Moreover, the fraction of vanadium in each sequential extraction characterized that residual fraction > oxidizable fraction > reducible fraction > acid soluble fraction. The bioaccumulation of vanadium from soil to plant was weak to intermediate absorption. Therefore, some countermeasures such as soil monitoring and remediation should be to take in the sooner future, especially in mining and smelting area.  相似文献   

6.
Concentrations of organochlorine pesticides (OCPs; dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB)) were investigated in 105 soil samples collected in vicinity of the chemical industrial parks in Tianjin, China. OCP concentrations significantly varied in the study area, high HCH and DDT levels were found close to the chemical industrial parks. The intensity of agricultural activity and distance from the potential OCP emitters have important influences on the OCP residue distributions. Principal component analysis indicates that HCH pollution is a mix of historical technical HCH and current lindane pollution and DDT pollution input is only due to technical DDT sources. The significant correlations of OCP compounds reveal that HCHs, DDTs and HCB could have some similar sources of origin.  相似文献   

7.
This study was performed to investigate the metal concentrations in muscle, liver, gonad, and gill of gilthead seabream (Sparus aurata L., 1758), European seabass (Dicentrarchus labrax L., 1758), and keeled mullet (Liza carinata Valenciennes, 1836) from Yelkoma Lagoon, northeastern Mediterranean region. So, the levels of cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead, and zinc in tissues of specimens from the lagoon were determined by inductively coupled plasma optical emission spectrometer. Concentrations of metals in muscles of the examined species ranged from 0.10 to 0.47 mg kg???1 for cadmium, 0.10 to 0.43 mg kg???1 for cobalt, 0.17 to 0.72 mg kg???1 for chromium, 0.62 to 1.03 mg kg???1 for copper, 28.9 to 52.3 mg kg???1 for iron, 0.75 to 0.96 mg kg???1 for manganese, 0.11 to 0.57 mg kg???1 for nickel, 0.19 to 0.47 mg kg???1 for lead, and 6.01 to 13.9 mg kg???1 for zinc, respectively. Additionally, metal concentrations in muscles of fish were assessed for human uses according to provisional tolerable weekly intake and provisional tolerable daily intake.  相似文献   

8.
Fourteen surface water and nine surface sediment samples were collected from the Peacock River and analyzed for organochlorine pesticides (OCPs) by gas chromatograph?Celectron capture detector (GC-ECD). All the analyzed organochlorine pesticides, except o,p ??-DDT, were detected in sediments from the Peacock River; but in the water samples, only ??-HCH, HCB, p,p ??-DDD, and p,p ??-DDT were detected at some sites. The ranges for total OCPs in the water and sediments were from N.D. to 195 ng l???1 and from 1.36 to 24.60 ng g???1, respectively. The only existing HCH isomer in the water, ??-HCH, suggested that the contamination by HCHs could be attributed to erosion of the weathered agricultural soils containing HCHs compounds. Composition analyses showed that no technical HCH, technical DDT, technical chlordanes, endosulfans, and HCB had been recently used in this region. However, there was new input of ??-HCH (lindane) into the Peacock River. The most probable source was water flowing from Bosten Lake and/or agricultural tailing water that was returned directly into the Peacock River. DDT compounds in the sediments may be derived mainly from DDT-treated aged and weathered agricultural soils, the degradation condition was aerobic and the main product was DDE. HCB in the sediment might be due to the input from Bosten Lake and the lake may act as an atmospheric deposition zone. There was no significant correlation between the concentrations of OCPs (including ??HCH, ??DDT, chlordanes, endosulfans, HCB and total OCPs) and the content of fine particles (<63 ??m). The concentrations of OCPs were affected by salinity.  相似文献   

9.
The spatial variability and temporal trend in concentrations of the organochlorine pesticides (OCPs), hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT), in soils and agricultural corps were investigated on an intensive horticulture area in Hohhot, North-West China, from 2008 to 2011. The most frequently found and abundant pesticides were the metabolites of DDT (p,p′-DDE, p,p′-DDT, o,p′-DDT and p,p′-DDD). Total DDT concentrations ranged from ND (not detectable) to 507.41 ng/g and were higher than the concentration of total HCHs measured for the range of 4.84–281.44 ng/g. There were significantly positive correlations between the ∑DDT and ∑HCH concentrations (r 2>0.74) in soils, but no significant correlation was found between the concentrations of OCPs in soils and clay content while a relatively strong correlation was found between total OCP concentrations and total organic carbon (TOC). β-HCH was the main isomer of HCHs, and was detected in all samples; the maximum proportion of β-HCH compared to ∑HCHs (mean value 54%) was found, suggesting its persistence. The α/γ-HCH ratio was between 0.89 and 5.39, which signified the combined influence of technical HCHs and lindane. Low p,p′-DDE/p,p′-DDT in N1, N3 and N9 were found, reflecting the fresh input of DDTs, while the relatively high o,p′-DDT/p,p′-DDT ratios indicated the agricultural application of dicofol. Ratios of DDT/(DDE+DDD) in soils do not indicate recent inputs of DDT into Hohhot farmland soil environment. Seasonal variations of OCPs featured higher concentrations in autumn and lower concentrations in spring. This was likely associated with their temperature-driven re-volatilization and application of dicofol in late spring.  相似文献   

10.
Some wetland plant species are adapted to growing in the areas of higher metal concentrations. Use of such vegetation in remediation of soil and water contaminated with heavy metals is a promising cost-effective alternative to the more established treatment methods. Throughout the year, composite industrial effluents bringing various kinds of heavy metals contaminate our study site, the East Calcutta Wetlands, a Ramsar site at the eastern fringe of Kolkata city (formerly Calcutta), India. In the present study, possible measures for remediation of contaminated soil and water (with elements namely, Ca, Cr, Cu, Pb, Zn, Mn, and Fe) of the ecosystem had been investigated. Ten common regional wetland plant species were selected to study their efficiency and diversity in metal uptake and accumulation. Results showed that Bermuda grass (Cynodon dactylon) had the highest total Cr concentration (6,601 ± 33 mg kg???1 dw). The extent of accumulation of various elements in ten common wetland plants of the study sites was: Pb (4.4?C57 mg kg???1 dw), Cu (6.2?C39 mg kg???1 dw), Zn (59?C364 mg kg???1 dw), Mn (87?C376 mg kg???1 dw), Fe (188?C8,625 mg kg???1 dw), Ca (969?C3,756 mg kg???1 dw), and Cr (27?C660 mg kg???1 dw) indicating an uptake gradient of elements by plants as Ca>Fe>Mn>Cr>Zn>Cu>Pb. The present study indicates the importance of identification and efficiency of metal uptake and accumulation capabilities by plants in relation to their applications in remediation of a contaminated East Calcutta Wetland ecosystem.  相似文献   

11.
Bovine milk samples were collected and analyzed during 1992 and 1998 from rural areas of 14 different districts of Haryana state for the presence of HCH and DDT residues. The study revealed that the mean residues of ΣHCH in raw bovine milk have declined by 67.5% while mean levels of ΣDDT have decreased by 92.8% during six years gap. The obtained results reveal that during 1992 p,p'-DDT was the main component followed by p,p'-DDD, α-HCH and β-HCH while in 1998, p,p'-DDE and β-HCH followed by p,p'-DDT were relatively more as compared to other isomers and metabolites of these pesticides.  相似文献   

12.
The organochlorine pesticide contamination in dietary sources has caused serious threat to the human progeny. The present study was therefore conducted to evaluate the pesticide contamination in wheat flour and drinking water from Jaipur City, Rajasthan, India using Gas Chromatograph. All the wheat and water samples were found to be contaminated with various organochlorine pesticide residues of DDT and its metabolites, HCH and its isomers, heptachlor and its expoxide and aldrin. The amount of pesticide detected in wheat flour was higher than the permissible limits prescribed by WHO/FAO. In drinking water only a few pesticides exceeded the permissible limits. Seasonal variations of pesticides residues were also observed during the study period.  相似文献   

13.
Organochlorine pesticides (OCPs) in sediment, water and biota samples from the coastal marine environment of Mumbai were analysed to elucidate their distribution in various environmental compartments. HCH isomers, dichlorodiphenyltrichloroethane (DDT) and its metabolites were the predominantly identified compounds in all the samples. High ratios of DDT to dichlorodiphenyldichloroethylene (DDE) were found in seawater samples. This indicates the presence of a significant source of DDT in this region. In sediment samples, the gamma-isomer contributed almost 55% to the total HCH, indicating a high affinity of the gamma-isomer towards the sediment. The levels of organochlorines in fish obtained from this region were found to be lower than the levels of organochlorines in fish in temperate regions.  相似文献   

14.
This study reports the concentration levels and distribution pattern of the organochlorine pesticide (OCPs) residues in the soil and surface water samples collected from the northern Indo-Gangetic alluvial plains. A total of 31 soil and 23 surface water samples were collected from the study region in Unnao district covering an area of 2150 km2 and analyzed for aldrin, dieldrin, endrin, HCB, HCH isomers, DDT isomers/metabolites, endosulfan isomers (α and β), endosulfan sulfate, heptachlor and its metabolites, α-chlordane, γ-chlordane and methoxychlor. In both the soil and surface water samples β- and δ-isomers of HCH were detected most frequently, whereas, methoxychlor was the least detected pesticide. The results showed contamination of soil and surface water of the region with several persistent organic pesticides. The total OCPs level ranged from 0.36–104.50 ng g–1 and 2.63–3.72 μg L–1 in soil and surface water samples, respectively.  相似文献   

15.
Ghaggar, one of the major rivers of northern India originating in outer Himalayas and flowing through the state of Punjab, Haryana, and Rajasthan, is put to multiple uses. Along its course of 464 km, it receives discharge from various cities and runoff from agricultural lands. Punjab and Haryana are two predominantly agricultural states of India using substantial amounts of agrochemicals, yet there are no reports available in literature on the level of pesticides in the stretch of river Ghaggar through Punjab and Haryana. This is the first report on pesticide pollution of the river Ghaggar in Haryana. Water samples along the 230-km stretch of the river in Haryana were analyzed for the presence of organochlorine insecticide residues. While aldrin and dieldrin were below detection limits, both hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) were traceable in all the water samples. High concentration of β-HCH among ΣHCH indicates old pollution source whereas predominance of p,p -DDT among ΣDDT reflects its recent use in the catchment area of the river. The concentrations of HCH and DDT in all the samples were above the permissible limits prescribed by the European Commission Directive for drinking purposes.  相似文献   

16.
Qiantang River is a typical river used for drinking water source, flowing through agricultural area in east China. Surface water samples at 45 sampling sites from the river were collected and analyzed for 13 organochlorine pesticides (OCPs) during six surveys in 2 years of 2005–2006. Sediments, soils, farmland runoff water and dry/wet deposition of this region were also measured for their OCPs residue in order to know possible source of OCPs contamination. The total OCPs concentrations in surface water were 7.68–615.2 ng/l. β-HCH, δ-HCH, Aldrin, Heptachlor, Heptachlor epoxide are the major OCPs in water. The maximum levels of OCPs in water were found in July, while significantly lower OCP concentrations were measured in January. Significant linear correlation was found between the concentration of HCH and that of total 13 OCPs in water. The measured OCP concentrations in sediments, soils, farmland runoff water and dry/wet deposition are discussed in relation to concentrations and patterns found in the surface water. Comparison of OCP levels in sediments and soils led to conclusion that erosion of soil contribute significantly to the contamination of water. The OCPs dry and wet deposition to water body was estimated to 0.49 and 0.86 ton/year, respectively. The ratio of α/γ-HCH and (DDE+DDD)/∑DDT in environmental matrix indicated there probably existed new OCPs input of lindane and dicofol into the river.  相似文献   

17.
Multiple residues of organochlorine insecticides were monitored in the agricultural fields near Farrukhabad in the vicinity of the River Ganga in northern India for one year (1991–1992). Almost all soil samples were found to be contaminated with residues of hexachlorocylohexane (HCH) and dichlorodiphenyl-trichloroethane (DDT). Residues of aldrin and endosulfan were also detected in a large number of samples. Heptachlor residues were scarcely detected. Alpha-HCH, pp-DDT and alpha-endosulfan were found to dominate over the other isomers/metabolites of HCH, DDT and endosulfan, respectively. The average concentration of dieldrin was more than that of aldrin. The concentrations of residues progressively increased up to a depth of 1 m.  相似文献   

18.
Multiple residues of organochlorine insecticides were monitored in Ganga river water in the district of Farrukhabad in northern Indian for one year (1991–1992). Almost all the samples were found to be contaminated with residues of HCH and DDT. Residues of aldrin, endosulfan and heptachlor were also detected in a larger number of samples. Alpha-HCH, pp-DDT and alpha-endosulfan were found to dominate over the other isomers of HCH, DDT and endosulfan, respectively. Enhanced percentage of beta-HCH suggests accumulation of this isomer in the aquatic environment. The average concentration of aldrin was more than that of dieldrin. Aldrin residues often exceeded the WHO guideline value for drinking water and the concentration of heptachlor occasionally exceeded the specified limits.  相似文献   

19.
The contamination of organochlorine pesticides hexachlorocyclohexane (HCH) and Dichlorodiphenyltrichloroethane (DDT) and their eco-environmental assessment in surface sediments from Lake Dongting, the second-largest freshwater lake in China, were studied. Concentrations of ∑HCH (=α-HCH + β-HCH + γ-HCH +δ-HCH) were 0.21--9.59 ng/g dry weight and those of ∑ DDT = p,p'-DDD+p,p'-DDE+o,p'-DDT+p,p'-DDT) ranged from under detectable limit to 10.15 ng/g dry weight. The ratios of α-HCH to γ-HCH were above 7 at most sampling sites while no or a small amount of β-HCH were found at all sites, suggesting the degradation of HCH used in the history and possibly current use of HCH in the region. The low ratios (below 2.0 in most cases) of (p,p'-DDE+p,p'-DDD) to p,p'-DDT and high levels of individual isomers of DDT at some sites also suggested that there have still been fresh inputs of DDT into Lake Dongting. Through the comparison between concentrations of HCH and DDT residues in sediments of Lake Dongting and those from other places in China and also from the results of our eco-environmental assessment, it can be concluded that Lake Dongting is the water body with high contamination of both HCH and DDT in its sediments in comparison with other water bodies in China.  相似文献   

20.
A modified LC-MS method for the analysis of mepiquat residue in wheat, potato, and soil was developed and validated. A hydrophilic interaction liquid chromatographic column has been successfully used to retain and separate the mepiquat. Mepiquat residue dynamics and final residues in supervised field trials at Good Agricultural Practice (GAP) conditions in wheat, potato, and soil were studied. The limits of quantification for mepiquat in all samples were all 0.007 mg kg?1, which were lower than their maximum residue limits. At fortification levels of 0.04, 0.2, and 2 mg kg?1 in all samples, recoveries ranged from 77.5 to 116.4 % with relative standard deviations of 0.4–7.9 % (n?=?5). The dissipation half-lives (T 1/2) of mepiquat in soil (wheat), wheat plants, soil (potato), and potato plants were 4.5–6.3, 3.0–5.6, 2.2–4.6, and 2.4–3.2 days, respectively. The final residues of mepiquat were below 0.153 mg kg?1 in soil (wheat), 0.052–1.900 mg kg?1 in wheat, below 0.072 mg kg?1 in soil (potato), and below 1.173 mg kg?1 in potato at harvest time. Moreover, pesticide risk assessment for all the detected residues was conducted. A maximum 0.0012 % of acceptable daily intake (150 mg kg?1) for national estimated daily intake indicated low dietary risk of these products.  相似文献   

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