Inhalation Exposure of Formulated Fenvalerate (20% EC): Toxicologic Alterations in Kidney of Rats

Abstract

Synthetic pyrethroid insecticides are logically gaining ground in agriculture, veterinary and in house pest control programmes (Leahey 1985) due to severe knock down effects on insects (Casida et al. 1983) and environment compatible over organochlorine insecticides with less toxicity to mammals (Aldridge 1990). Toxicity of pyrethroids was studied in different animals and it was found that these insecticides have neurotoxic (Crafton et al. 1995) and genotoxic effects (Amer et al. 1993). He et al. (1989) reviewed 573 cases of acute pyrethroid poisoning caused by deltamethrin followed by fenvalerate. Importantly, all of the pyrethroid exposures were attributed to formulated products, specified as emulsifiable concentrates, therefore undoubtedly containing organic solvent and surfactant. Thus, the health effects reported are not due to pyrethroids alone, but also due to the formulated solvent, surfactant and other uncharacterized co-exposures (Yang et al. 2002). Xylene may also be present in the concentrates (IARC 1989). Fenvalerate is also formulated in combination with oxydemeton–methyl (Royal society of chemistry 1986). Fenvalerate [(RS)-a-cyano-3-phenoxy benzyl (RS)-2-(4chlorophenyl)] isovalerate, a photo stable pyrethroid insecticide has been used worldwide for control of wide range of pest insects of cotton and vegetables (Shiba et al. 1990). India is an agricultural country and the farmers use array of pesticides for controlling agricultural pests and disease causing vectors. Fenvalerate is one among the several pesticides used in large quantity for plant protection purpose. Pesticides may reach the water bodies through different modes like, run-off from agricultural fields along with rainwater, accidental spills, atmospheric transport and also by direct application (Mushingeri and David 2005). Reports in respect of toxicity of synthetic pyrethroids including formulated fenvalerate in experimental animals is very scarce. Earlier studies from this laboratory reported the pulmonary toxicity and steroidogenic alterations in fenvalerate inhalation exposed rats (Mani et al. 2001, 2002). However reports on nephrotoxicity of formulated fenvalerate in individuals exposed through inhalation is not available in literature. The purpose of present work was to investigate the effects of formulated fenvalerate (20% EC) in kidney of rats.