Operational use of neem oil as an alternative anopheline larvicide. Part B: Environmental impact and toxicological potential.

This study was conducted to investigate the preliminary environmental and mammalian toxicology of neem oil, temephos and chlorpyriphos-methyl/fenitrothion. Culex pipiens, Daphnia magna and Gambusia affinis were used to study environmental impact. A high level of toxicity was observed, with slight differences between organisms. The emulsifiers individually also displayed toxicity towards the tested organisms. Up to 90 days daily oral crude neem oil treatment (5 g/kg body weight) of laboratory mice did not cause any significant changes in weekly body weight gain, nor in serum liver damage indicators, direct bilirubin or total bilirubin. Blood parameters of treated mice up to 90 days were not statistically different from those of control mice. Neem oil could be used as an environmentally friendly alternative to the traditional chemical anopheline larvicides.