Impact assessment of pesticide residues in fish of Ganga river around Kolkata in West Bengal.
ABSTRACT An investigation was conducted from 2001 to 2005 for determining the residual concentration of five pesticides, viz., total-HCH, total-DDT, total-Endosulfan, Dimethoate and Malathion in fish samples collected from various points of the river Ganga. Fish samples were analyzed for pesticide residues using standard laboratory procedures by GC method. It was found that total-HCH concentration remains above the MRL values for maximum number of times in comparison to four other pesticides. The pesticide contamination to fish may be due to indiscriminate discharge of polluted and untreated sewage-sludge to the river. The pesticide contents in some places are alarming. Thus proper care, maintenance, treatment and disposal of sewage water and sludge are most vital and should be the prime thrust for the nation.
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ABSTRACT: Agricultural nonpoint source (NPS) runoff may result in significant discharges of pesticides, suspended sediments, and fertilizers into estuarine habitats adjacent to agricultural areas or downstream from agricultural watersheds. Exposure of estuarine fin fish and shellfish to toxic levels of pesticides may occur, resulting in significant declines in field populations. Integrated pest management (IPM), best management practices (BMP), and retention ponds (RP) are risk management tools that have been proposed to reduce the contaminant risk from agricultural NPS runoff into estuarine ecosystems. Field studies were conducted at three sites within coastal estuarine ecosystems of South Carolina (SC) from 1985 to 1990 that varied in terms of the amount and degree of risk reduction strategies employed. An intensively managed (IPM, BMP, and RP) agricultural treatment site (TRT) was studied for pesticide runoff impacts. From 1985 to 1987, there were minimal (some IPM and BMP) management activities at TRT, but from 1988 to 1990, TRT was managed using an intensive risk reduction strategy. A second unmanaged agricultural growing area, Kiawah (KWA), was also studied and compared with TRT in terms of pesticide runoff and the resulting impacts on grass shrimp (Palaemonetes pugio) and mummichogs (Fundulus heteroclitus). A third, non-agricultural, reference site (CTL) was used for comparing results from the managed and unmanaged agricultural sites. In situ toxicity tests and field samples of the grass shrimp populations were conducted at each site and compared in terms of survival and the effectiveness of current risk reduction strategies. Significant runoff of insecticides (azinphosmethyl, endosulfan, and fenvalerate) along with several fish kills were observed at TRT prior to the implementation of rigorous risk reduction methods. A significant reduction of in stream pesticide concentrations (up to 90%) was observed at TRT following the implementation of strict NPS runoff controls, which greatly reduced impacts on estuarine fish and shellfish. At the unmanaged KWA, continued impacts due to the runoff of these insecticides were observed, along with several fish kills. Additional monitoring indicated that gravid female grass shrimp populations from KWA had elevated levels of P-glycoprotein (P-gp), a multidrug resistance protein, which may transport various pesticides across cellular membranes. Comparison of field results with laboratory toxicity tests established that pesticide exposure was the primary cause of observed field impacts at each site. These findings clearly indicate the value of an integrated risk reduction strategy (BMP, IPM, and RP) for minimizing impacts from NPS agricultural pesticide runoff.Toxicology and Industrial Health 01/1999; 15(1-2):200-13. · 1.56 Impact Factor
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ABSTRACT: The presence of pesticide residues in rain, throughfall, stemflow and in ambient air in two Italian forests affected by the forest damage phenomenon were investigated. Pesticides measured were: alachlor, atrazine, carbaryl, 2,4-D, diazinon, dichlobenil, fluazifop-butyl, MCPA, parathion, phorate and trifluralin. Rainwater samples were collected from May to October 1988 at Vallombrosa and Renon, air and atmospheric particulates were sampled during April-June 1989, only at Vallombrosa. A total of 146 samples of rainfall and 20 samples of ambient air were analysed and 49 out of 166 samples contained at least one active ingredient. Herbicides were more frequent than insecticides, and their concentrations were also higher (max 3.44 microg litre(-1)).Environmental Pollution 02/1993; 80(1):31-9. · 3.73 Impact Factor
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ABSTRACT: A pesticide store near Hargeisa (Somaliland) was damaged by bombing in May 1988, and subsequently looted by local people, who removed and drained drums of chemicals. Assessment of the effects of resultant spillage during the dry season, March/April 1993, established that pesticides, mainly organochlorines (dieldrin and products and BHC isomers)and organophosphates (fenitrothion and malathion) had contaminated 3700 sq mof soil at up to 3728.0 (geometric mean 149.0) ppm (5180.0 g/m3)total insecticides. Reptiles avoided contamination above 1 ppm, and were absent above 10 ppm. Experimental contact with highly contaminated soil caused death in lizards-Hemidactylus parkeri and Mabuyas. striata-after 26.5 and 33. 5 h, respectively (residue levels elevated over 2000-and 149-fold), and 100% mortality within 65 min in frogs Tomopterna cryptotis (geometric mean residue level elevated 168-fold). Sediment 350 m downstream of the spill contained dieldrin at 0.50 ppm (0.03-0.05 ppm after 1.6, to 9.0, km). Whole body residues of spillage vicinity lizards were up to 1.52 ppm wet weight (193.6 ppm lipid) total insecticides. Geometric mean of 0.36 ppm was elevated fivefold above mean background level of Hargeisa lizards in the valley below. Dieldrin and products was highest; the level of BHC isomers was also significantly higher than DDT. Geometric mean total insecticide level in Chalcides ragazzii and H. parkeri was four times higher than in surface-dwelling Pseuderemias smithi. Reptile species richness was habitat-influenced. Frogs without abnormalities present in mud of river-bed wells indicated uncontaminated ground water (organochlorine residues undetected). Low levels in frogs, and of M. s. striata in thevicinity of wells [geometric means 0.09 and 0.07 (ranges 0-0.48 and 0.01-0.31) ppm, respectively], implied that by 2.7 km downstream of the spill few residues were entering food chains.Archives of Environmental Contamination and Toxicology 02/1997; 32(1):80-93. · 2.01 Impact Factor