Endosulfan, an organochlorine pesticide, is a broad spectrum contact insecticide widely used in pest control. It is used in a wide range of crops including cereals, coffee, cotton, fruit, oil seeds, potato, tea and vegetables. There is a global concern over the acute toxicity of endosulfan. Technically endosulfan is a mixture of two isomers – alpha-endosulfan and beta-endosulfan a mixed proportion of 70% and 30% respectively. The endosulfan residues of toxicological concern are alphaendosulfan, beta-endosulfan and endosulfan sulfate. The sulphate is regarded as being equally toxic and of increased persistence in comparison with the parent isomers (USEPA-2010). The world Health Organization (WHO) classifies endosulfan in Category 2 (moderately hazardous).
United States Environmental Protection Agency (USEPA) classifies endosulfan as Category 1b - highly hazardous2The Industrial Toxicological Research Centre (ITRC) in India the nodal centre for the Regional Based Assessment of Persistent Toxic Substances (PTS) for the Indian Ocean region by the United Nations Environment Programme-Global Environment Facility (UNEP-GEF) classifies endosulfan as Extremely Hazardous.
The Intergovernmental Forum on Chemical Safety (IFCS) identified endosulfan as an acutely toxic pesticide that poses significant health problems for developing countries and economies in transition.4 According to the International Programme on Chemical Safety, INCHEM (1998) the Acute oral LD50(Lethal Dose) for rats is 80 mg/kg and the inhalation LC50(Lethal Concentration) (1 hour) for rats > 21 mg/L in air. However according to the USEPA the LD50 for oral exposure is 30mg/kg bw and LC50 is less than and equal to 0.5mg/L.