Endosulfan

About: Endosulfan is a research topic. Over the lifetime, 1506 publications have been published within this topic receiving 30861 citations. The topic is also known as: Benzoepin & Endosulphan.

Insecticide resistance in five major insect pests of cotton in India

Abstract: Insecticide resistance to representatives of commonly used insecticide groups (pyrethroids—cypermethrin; organophosphates—chlorpyriphos; cyclodienes—endosulfan) was determined in five major insect pests of cotton from the main cotton growing regions of India with emphasis on Andhra Pradesh and Maharashtra. The cotton bollworm Helicoverpa armigera (Hubner) exhibited widespread resistance to cypermethrin with 23–8022-fold resistance being recorded in field strains. Resistance to endosulfan and chlorpyriphos was low to moderate in H. armigera. The overall resistance of the pink bollworm Pectinophora gossypiella (Saunders) to pyrethroids was low. However, high resistance levels of 23–57-fold to endosulfan were recorded in some areas of Central India. Resistance to chlorpyriphos was high in the Medak, Bhatinda and Sirsa strains from North India. The majority of the Spodoptera litura (Fab.) strains collected in South India exhibited high resistance levels of 61–148-fold to cypermethrin. Resistance to endosulfan was high only in two strains, collected from Bhatinda and Karimnagar in North India. The S. litura strains from South India exhibited high levels of resistance at 45–129-fold to chlorpyriphos. Insecticide resistance in Earias vittella (Fab.) was low to moderate in the Sirsa and Sriganganagar strains from North India. Bemisia tabaci (Genn.) exhibited moderately high levels of resistance to cypermethrin, but resistance to endosulfan and chlorpyriphos was negligible in the field strains tested. The implications of resistance for cotton pest management in India are discussed.

Endosulfan, a global pesticide: a review of its fate in the environment and occurrence in the Arctic.

Abstract: This review investigates the fate and behaviour of endosulfan, a current-use organochlorine pesticide, in temperate environments and the Arctic. Usage data and patterns, physical-chemical properties, environmental partitioning and degradation, environmental levels, global distribution and temporal trends are evaluated and discussed in the context of criteria that designate a substance as a persistent organic pollutant. Endosulfan is one of the most abundant OC pesticides in the global atmosphere and is capable of undergoing long range transport to remote locations such as the Arctic. Degradation of the two isomers, alpha- and beta-endosulfan, does occur in temperate/tropical soil and aquatic systems, both by abiotic and biotic processes, although this is highly dependent on the prevailing environmental conditions. Endosulfan sulfate is the major metabolite and this recalcitrant compound has been detected in air and is present in remote mountain lake sediments, although in comparison to alpha-endosulfan, data for this compound in the wider environment are lacking. Temporal trends from ice/snow cores as well as mountain lake sediments reveal a marked increase in endosulfan accumulation from the 1980s onwards. Furthermore, unlike other 'legacy' OC pesticides, levels of alpha-endosulfan do not show a decline in atmospheric monitoring data, reflecting ongoing use of this pesticide in the northern hemisphere. Endosulfan is present at low concentrations (relative to the pesticide, lindane) in surface Arctic Ocean waters, with the atmosphere likely to be the major contemporary source. Residues of endosulfan have been detected in marine biota for different geographical regions of the Arctic, with higher bioaccumulation factors (>10(3)-10(7)) for zooplankton and various species of fish, compared to studies in warmer/temperate systems. Endosulfan is present in marine mammals, although there is uncertainty in the various Arctic biota datasets due to differences in analytical techniques. For some biota, biomagnification factors for alpha-endosulfan are >1, notably from fish to seal, although there is a wide variability in values between the same species for different regions of the Arctic. There is little if any evidence of trophic magnification of alpha-endosulfan in well-defined marine foodwebs, with some evidence of bio-dilution at higher trophic levels, presumably due to increased metabolism. Endosulfan does fulfil several of the criteria under the UNEP Stockholm Convention for designation as a persistent organic pollutant. The alpha- and beta-isomer have similar physical-chemical properties and environmental behaviour to some of the obsolete organochlorine pesticides, although an assessment of their persistence and toxicity should be viewed alongside endosulfan sulfate, as 'Sigmaendosulfan'. Persistence of 'Sigmaendosulfan' coupled to ongoing use of endosulfan pesticides, will ensure continued long-range transport and contamination of remote environments.

Effects of an herbicide and an insecticide on pond community structure and processes

Abstract: Virtually all species live within complex food webs, and many of these organisms are exposed to contaminants. However, we know little about how community processes, such as competition and predation, influence susceptibility to contaminants or how different types of contaminants shape communities. The objective of our study was to determine how realistic concentrations of the herbicide atrazine and the insecticide endosulfan influence the structure of a pond community when the presence of common community members was manipulated. We employed a factorial design in mesocosms to evaluate the effects of pesticide treatments (25 mg/L of atrazine, 10 mg/L of endosulfan, solvent control; two pulses separated by two weeks) and the presence or absence of wood frog tadpoles (Rana sylvatica), adult snails (Planorbella trivolvis), and caged dragonfly larvae (Anax junius) on a freshwater community. Tadpoles, snails, and chironomid larvae, Polypedilum sp. (Dipterans), all competed for periphyton. As a result, tadpoles reduced the survival, mass, and reproduction of snails; snails reduced the growth, development, inactivity, and dragonfly avoidance of tadpoles; snails and tadpoles reduced the abundance of chironomid larvae; and chironomid larvae reduced snail mass. The adverse effect of snails on tadpole growth and behavior was greater in the presence of the caged tadpole predator, A. junius. Neither pesticide affected dragonfly survival, but endosulfan directly reduced zooplankton (Daphnia), and atrazine indirectly reduced chironomid abundance. Atrazine also directly decreased periphyton, and endosulfan decimated chironomid larvae, resulting in indirect increases and decreases in competition for both snails and tadpoles, respectively. Consequently, relative to endosulfan, atrazine tended to decrease snail mass and reproduction and reduce tadpole mass, development, inactivity, refuge use, and dragonfly avoidance. However, the indirect effects of pesticides depended upon the presence of heterospecifics. The indirect benefit of endosulfan on snail mass was greater in the presence of caged dragonfly larvae, and endosulfan's indirect benefit on tadpole mass was greater in the absence of snails. The effect of pesticides on tadpole activity depended on both caged dragonflies and snails. Thus, environmentally realistic concentrations of pesticides directly and indirectly shaped species responses and community composition, but the initial composition of the community influenced these pesticide effects. These results emphasize the importance of quantifying the effects of contaminants within complex natural communities.

Metabolic pathways utilized by Phanerochaete chrysosporium for degradation of the cyclodiene pesticide endosulfan.

Abstract: Recent studies have shown that cultures of white rot fungi not favoring the production of lignin and manganese peroxidases are effective in degrading certain xenobiotics In this study we have used endosulfan as a model xenobiotic to assess the enzymatic mechanisms of pesticide metabolism under ligninolytic (nutrient-deficient) and nonligninolytic (nutrient-rich) culture conditions Rapid metabolism of this chlorinated pesticide occurred under each nutrient condition tested However, the extent of degradation and the nature of the metabolic products differed for nutrient-deficient and nutrient-rich media The pathways for endosulfan metabolism were characterized by analysis of the fungal metabolites produced The major endosulfan metabolites were identified by gas chromatography-electron capture detection and gas chromatography-mass spectrometry as endosulfan sulfate, endosulfan diol, endosulfan hydroxyether, and a unknown metabolite tentatively identified as endosulfan dialdehyde The nature of the metabolites formed indicates that this organism utilizes both oxidative and hydrolytic pathways for metabolism of this pesticide Piperonyl butoxide, a known cytochrome P-450 inhibitor, significantly inhibited the oxidation of endosulfan to endosulfan sulfate and enhanced hydrolysis of endosulfan to endosulfan diol We suggest that the metabolism of endosulfan is mediated by two divergent pathways, one hydrolytic and the other oxidative Judging by the inactivity of extracellular fluid and partially purified lignin peroxidase in metabolizing endosulfan, we conclude that metabolism of this compound does not involve the action of extracellular peroxidases