Malathion is a widely organphosphorus insecticide used in agriculture, which shows strong insecticidal effects. However, the use of this insecticide leads to disruption in metabolic pathways. The aim of this study is to evaluate the acute effects of malathion on metabolic parameters in Wistar rats. Malathion was administered orally to rats at a dose of 400 mg/kg body weight dissolved in corn oil. Glucidic and lipidic status were analyzed in plasma, cholinesterase activities were also determined. Malathion induces a transitory hyperglycaemia which correlated with depletion on glycogen content. Plasma triglycerides and LDL level increased significantly in malathion treated-rats. HDL rate was unchanged and cholesterol plasma content decrease transitory but rapidly reached a normal level. Results of this study indicate, clearly, that malathion in acute exposure leads to a disruption of lipid metabolism with an enhancement in LDL and triglyceride contents and may play an important role in the development of atherosclerosis and cardiovascular disease. Disruption in plasma lipid profile may leads to a kind of insulin resistance which results in hyperglycaemia. (C) 2008 Elsevier B.V. All rights reserved