Concentration levels of endosulfan in biological material (report of three cases)

Endosulfan poisoning: An overview

Endosulfan, an organochlorine (OC) insecticide, is a widely used agricultural pesticide, despite its life threatening toxic effects. In this review, the pharmacokinetics of endosulfan, mechanism of endosulfan toxicity, clinical presentations and management, histopathological findings, and toxicological analysis are described, in addition to its environmental toxicity. The toxic effects of endosulfan can affect many organs and systems presenting in a wide array of signs and symptoms. Although termed a restricted OC-classed pesticide, it continues to be used, especially in the developing world, owing to its beneficial effects on agriculture. Several cases of endosulfan poisoning have been reported from different regions of the world. Whether accidental or intentional, endosulfan ingestion proves to be fatal unless immediate, aggressive treatment is initiated. Management is mainly supportive as no antidote exists for endosulfan poisoning as yet. The use of endosulfan needs to be strictly regulated and eventually banned worldwide altogether to lower the current morbidity and mortality resulting from this pesticide. Additionally, monitoring biological samples, using non-invasive techniques such as breast milk sampling, can provide an effective method of observing the elimination of this environmentally persistent organic pollutant from the general population.

Accumulation of endosulfan in wild rat, Rattus norvegious as a result of application to soya bean in Mazoe (Zimbabwe)

An assessment of levels of endosulfan and endosulfan sulphate in rats collected from a plot sprayed with endosulfan was carried out for a period of four months. The analysis was carried out in the livers, muscles and fatty tissues of the rats using Gas Chromatography. Samples were ground with sodium sulphate and aluminium oxide and the analyte soxhlet extracted with hexane. The extract was then cleaned by florisil column chromatography. Levels of endosulfan in rats were found to range in livers from 0.356 to 5.807 ppb, in muscles from 0.089 to 5.167 ppb and in fatty tissues from 0.083 to 4.785 ppb. Levels of endosulfan sulphate correlated well with those of endosulfan and ranged in livers from 0.00 to 3.96 ppb, in muscles from 0.00 to 3.37 ppb and in fatty tissue from 0.00 to 2.93 ppb. In the control rats samples, collected from an unsprayed area in the city of Harare (University of Zimbabwe), no endosulfan could be detected.

Application of biological measures for stream integrity assessment in south-east Brazil

The sensitivity of eleven metrics using macroinvertebrate assemblages were evaluated in an environmental gradient in a tropical river in south-east Brazil. Eight sites were sampled in an altitudinal range of 160-650 m.a.s.l. during 1999 (April and August) and 2000 (February). Four substrates were sampled at each site: riffle litter, pool litter, stony substrates and sediment. Correspondence Analysis indicated that assemblages were primarily more influenced by physical changes (like deforestation and erosion processes) than the water chemistry. The sensitivity of each metric was evaluated through the application of box-and-whisker plot method by its power to assess impairment (metrics should be able to discriminate reference sites from impaired sites) and natural variability (metrics should not discriminate two reference sites). Metrics that failed in at least one of the above premises were not considered as sensitive. In this study, the most sensitive metrics were Shannon index, BMWP-ASPT, %_EPT, and relative abundance of EPT to Chironomidae.

Analysis of endosulfan and its metabolites in rat plasma and selected tissue samples by gas chromatography-mass spectrometry

A method has been developed for the determination of trace levels of alpha-endosulfan, beta-endosulfan, endosulfan sulfate, and endosulfan diol in rat plasma and tissue samples. Endosulfan and its metabolites in the plasma samples were extracted with solid-phase extraction Chromabond-end-capped C18 cartridges and analyzed by a Shimadzu QP-5050A gas chromatograph-mass spectrometer (GCMS) with quadrupole detector in selected-ion-monitoring mode. The analysis of endosulfan and its metabolites in liver and kidney samples involved solvent extraction, Florisil solid-phase-extraction cleanup, and quantitation by GCMS. Recovery experiments for the plasma and tissue samples were conducted over concentration ranges of 10-100 ng mL(-1) and 100-1000 ng mL(-1), respectively. The method was applied to the analysis of trace levels of endosulfan and its metabolites in plasma and tissue samples collected from an animal study. Trace levels of alpha-endosulfan and beta-endosulfan in the ranges of undetectable to 3.11 microg g(-1) and undetectable to 1.19 microg g(-1), respectively, were detected in the kidney samples, whereas trace levels of endosulfan sulfate in the range of 0.02-0.22 microg g(-1) were detected in the liver samples of rats. Neither endosulfan nor its metabolites was detected in any of the plasma samples.

Effects of single and repeated administration of endosulfan on behaviour and its interaction with centrally acting drugs in experimental animals: a mini review

The organochlorine cyclodiene insecticide, endosulfan readily penetrates into the brain. The neurotoxic action of endosulfan has been attributed to its α-isomer. Endosulfan sulphate which is a chief metabolite of endosulfan seems to contribute to its acute neurotoxic action which is manifested by clonic convulsions in experimental animals. Convulsant and proconvulsant effects of endosulfan are apparent after its chronic exposure at low dose levels. These effects have been attributed to its γ-aminobutyric acid antagonistic action. Repeated exposure to low doses has resulted in behavioral changes too. Endosulfan-induced hyper-excitability has been associated with its muscarinic receptor stimulating action. The insecticide has been shown to produce aggressive behaviour and learning impairment by activating serotonergic mechanism. A dopaminergic involvement has been suggested for endosulfan-induced hypermotoractivity and circling movement. Animals exposed chronically to low doses of the insecticide have responded more markedly than control animals to the pharmacological actions of diazepam, chlorpromazine, pentobarbital and ethanol. The findings reviewed here emphasize awareness that chronic occupational exposure to low doses of endosulfan may result not only in behavioral abberations but in hazardous interaction with centrally acting drugs too.

Acute intoxication by endosulfan

The authors report six patients with acute endosulfan intoxication. The symptoms of nausea, vomiting, headache, and dizziness began 2.7 +/- 0.5 h after ingestion; in four cases the patients had been hospitalized but were asymptomatic. All had severe metabolic acidosis with high anion gap and hyperglycemia; five of six had decreased blood platelets. Three patients had pulmonary aspiration, and five required mechanical ventilation. The one fatality followed acute renal failure, disseminated intravascular coagulation, thrombi in the pulmonary arteries and aorta, and cardiogenic shock. In this patient the blood endosulfan was 2.85 mg/L versus a mean of 0.48 mg/L in the survivors.