MOSQUITO REPELLENT PYRETHROID INDUCED BIOCHEMICAL AND BIOPHYSICAL CHANGES IN PLASMA AND ANTIOXIDANT STATUS IN HUMAN MALE VOLUNTEERS EXPOSED TO LONG TERM ALLETHRIN AND PRALLETHRIN INHALATION

Allethrin and prallethrin are type-I pyrethroids commonly used for domestic and agricultural purposes to get protection from mosquitoes and other insects. Use of this pyrethroids for longer durations (i.e. inhalation 8 hours per day not more than 10 hours per day) and for prolonged periods in the form of coils and mats, results in biochemical and biophysical changes in erythrocyte biomembrane has been established. The effect of allethrin and prallethrin on plasma nitrite and nitrate concentrations on the activities of red cell enzymes acetyl cholinesterase (AChE) and antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) the content of reduced glutathione (GSH) and erythrocyte membrane lipid peroxidation (LPO) were determined in human male volunteers who has been exposed to allethrin and prallethrin for the past 7-10 years. The results were compared with controls (who did not use any mosquito repellents). It was observed that there was an increase in plasma nitrite and nitrate, increase in activities of defense enzymes and observed decrease levels of erythrocyte membrane lipid peroxidation (LPO), but a decreased activity of acetyl cholinesterase (AChE) was observed in allethrin and prallethrin exposed subjects. This study revealed a modest increase in nitric oxide production, increased antioxidant status followed by enhanced oxidative stress. A possible role of nitric oxide in the above changes cannot be ruled out, for which further experimentation is required.