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A new sensitive analytical procedure has been developed for the determination of residues of endosulfan in human blood samples. The method involves the extraction of residues of endosulfan from blood samples by the addition of 60% sulfuric acid at 10 degrees C, liquid/liquid partitioning by using hexane and acetone mixture (9:1) and quantification by using GC-ECD. Residues of endosulfan in blood samples were quantified as the sum of alpha-endosulfan, beta-endosulfan, endosulfan sulfate and endosulfandiol. The influence of temperature during the extraction has been studied. Recovery experiments were conducted over the concentration range 1.0-50 ng ml(-1) and the relative standard deviation calculated. The method was found to be sufficiently sensitive to quantify the residue of total endosulfan up to the 1.0 ng ml(-1) level. The recovery was 92% with a calculated relative standard deviation of 1.96%. Conversion of endosulfan to endosulfandiol is found to be less than 0.5% under the defined conditions. The method was applied to the analysis of residue contents of endosulfan and its metabolites in blood samples collected from the exposed population. The data obtained has been confirmed by GC-MS-EI in selective ion monitoring (SIM) mode. 相似文献
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Enzymatic biomarkers in the crab Carcinus maenas from the Minho River estuary (NW Portugal) exposed to zinc and mercury 总被引:1,自引:0,他引:1
Zinc and mercury are common contaminants of estuaries and coastal ecosystems where they may induce adverse effects on the biota. Carcinus maenas is a key-species in several European estuaries, living in close association with the sediment where a considerable number of environmental contaminants, including zinc and mercury may accumulate. In the present study, the acute effects of zinc and mercury on C. maenas from the Minho River Estuary (NW Portugal) were investigated by using the activity of the enzymes cholinesterase (ChE), lactate dehydrogenase (LDH) and glutathione S-transferases (GST) as effects' criteria. Crabs were exposed for 96h to several concentrations of Zn(2+) (0, 1.84, 3.71, 7.39 and 14.79mg/l) or Hg(2+) (0, 0.09, 0.19, 0.37 and 0.74mg/l). The choice of Zn(2+) test concentrations was based on the LC50 value (14.86mg/l) determined in a first part of the study, while the choice of Hg(2+) concentrations was based on values from the literature. At the end of the bioassays, eye, muscle and hepatopancreas tissues were isolated and used for ChE, LDH and GST determinations, respectively. Zinc significantly inhibited ChE activity (p<0.05, EC50=14.68mg/l), caused significant alterations of GST activity (p<0.05) and induced LDH activity (p<0.05) at the exposure of 14.79mg/l. Mercury significantly inhibited ChE activity (p<0.001, LOEC=0.09mg/l, EC50=0.235mg/l) and increased both GST (p<0.05, LOEC=0.774mg/l) and LDH activities (p<0.05, LOEC=0.119mg/l). These results suggest that both metals interfere with cholinergic neurotransmission in C. maenas by inhibiting ChE activity. In addition, they also interfere with GST activity and this may reduce the capacity of detoxification of some chemicals and/or to increase the probability of oxidative stress to occur. Furthermore, both metals increase LDH activity, suggesting an interference with energy production pathways. Therefore, the presence of zinc and mercury in estuaries at concentrations in the mg/l or mug/l range, respectively, may have a negative impact on C. maenas. 相似文献
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Gopal Jeya Elumalai Ganesan Tajuddin Aimi Asilah Haji Ito Yoshikazu Vajiravelu Sivamurugan Ravikumar Dhanalakshmi 《Journal of Polymers and the Environment》2022,30(6):2614-2630
Journal of Polymers and the Environment - In this investigation, the use of phosphotungstic acid (PWA) and phosphomolybdic acid (PMA) as well as Zn2+ containing kaolin and bentonite explored for... 相似文献
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Atmakuru R Perumal Elumalai T Sivanandam S 《Environmental monitoring and assessment》2007,130(1-3):519-528
Long term stability of sulfosulfuron was investigated in subsoil under the natural wheat cropping conditions. Experiments
were conducted by applying a commercial formulation of sulfosulfuron on soil at 50 g/ha and 100 g/ha. To understand the factors
influencing the persistence of residues two different experiments were conducted. In one experiment wheat crop was cultivated
once at the beginning of the two years study period and subsequently the plots were kept undisturbed for the remaining period.
In another experiment cultivation of subsequent crops were continued during the study period. In both the cases sulfosulfuron
was applied only once at the beginning of the study. Representative soil samples were collected from the depths viz., 0–5,
15, 30, 45, 60 and 90 cm on different pre determined sampling occasions 50, 100, 200, 300, 400, 500 and 600 days after the
application of the herbicide. The collected soil samples were analyzed for the residues of sulfosulfuron. Under the influence
of continuous cropping conditions residues of sulfosulfuron were found to be relatively low when compared with the soil samples
collected from the agriculture plots maintained without any cultivation. The residues detected are in the range 0.001 to 0.017 μg/g.
Samples collected from the depth, at 30 to 45 cm showed higher residual concentrations. Soil samples were also showed the
presence of break down products. The data has been confirmed by LC–MS/MS. The relation between residue content of sulfosulfuron
and the factors contributing the stability of herbicide concentration were also studied. 相似文献
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Adoption of soil test-based nutrient management is important for achieving sustainable development of agriculture. The present study analysed the factors influencing the adoption of soil nutrient management technology package comprising adoption of soil test and recommended fertiliser by paddy farmers in the southern Indian state of Karnataka by using field survey data. Bivariate probit model was used to estimate the sequential adoption decisions on soil test and fertiliser application technologies. The study results showed that farmers’ training on fertiliser application and education had positive and significant effect on adoption of soil nutrient technology package. The likelihood of adoption of soil test technology decreases with increase in distance measured from farm to soil test laboratory. Availability of fewer family labour increases the probability of adoption of soil nutrient management technology. These results have significant policy implications for provision of soil testing facilities nearer to villages and for conducting periodical training programmes for encouraging the farmers to adopt soil test-based nutrient management. 相似文献
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Hsi-Hsien Yang Sunil Kumar Gupt Narayan Babu Dhital Lin-Chi Wang Suresh Pandian Elumalai 《环境科学学报(英文版)》2020,32(6):245-255
Volatile organic compounds(VOCs) are the important precursors of the tropospheric ozone(O_3) and secondary organic aerosols(SOA),both of which are known to harm human health and disrupt the earth's climate system.In this study,VOC emission factors,O_3 and SOA formation potentials were estimated for two types of industrial boilers:coal-fired boilers(n=3) and oil-fired boilers(n=3).Results showed that EVOCs concentrations were more than nine times higher for oil-fire d boilers compared to those for coal-fired boilers.Emission factors of ΣVOCs were found to be higher for oil-fired boilers(9.26-32.83 mg-VOC/kg) than for coal-fired boilers(1.57-4.13 mg-VOC/kg).Alkanes and aromatics were obtained as the most abundant groups in coal-fired boilers,while oxygenated organics and aromatics were the most contributing groups in oil-fired boilers.Benzene,n-hexane and o-ethyl toluene were the abundant VOC species in coal-fired boiler emissions,whereas toluene was the most abundant VOC species emitted from oil-fired boilers.O_3 and SOA formation potentials were found 12 and 18 times,respectively,higher for oil-fired than for coal-fired boilers.Total OFP ranged from 3.99 to 11.39 mg-O_3/kg for coal-fired boilers.For oil-fired boilers,total OFP ranged from 36.16 to 131.93 mg-O_3/kg.Moreover,total secondary organic aerosol potential(SOAP) ranged from 65.4 to 122.5 mg-SOA/kg and 779.9 to 2252.5 mg-SOA/kg for the coal-fired and oil-fired boilers,respectively. 相似文献
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Vengadesan Elumalai Senthil Ramalingam 《Environmental science and pollution research international》2022,29(12):17241-17259
Environmental Science and Pollution Research - The thermal performance of a flat plate solar water collector (FPSWC) depends on the amount of solar energy absorbed by the absorber, the quantity of... 相似文献
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Gopal Jeya Elumalai Ganesan Tajuddin Aimi Asilah Haji Ito Yoshikazu Vajiravelu Sivamurugan Ravikumar Dhanalakshmi 《Journal of Polymers and the Environment》2022,30(7):3119-3119
Journal of Polymers and the Environment - 相似文献
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