Neurotoxicity Evaluation of Chlorpyrifos Exposure with Caenorhabditis elegans

Chlorpyrifos, a broad spectrum orgnaophosphorus insecticide, is extensively used in agricultural and household insect control, but the potential health effects associated human exposure to low levels is unclear, which has been subject of increasing concern in the last years. However, few studies about chlorpyrifos toxicity have been conducted in the model organism Caenorhabditis elegans, which can complement both in vitro and in vivo mammalian models in toxicology. In the present study, Caenorhabditis elegans was chosen to evaluate the neurotoxicity of chlopyrifos with 0.003, 0.03, 0.3, and 3 mg/L after 4h exposure by analyzing basic movements, feeding ability and inhibition of acetylcholinesterase activity. Results indicated that forward turn frequency and acetylcholinesterase activity were reduced significantly compared with control at the highest concentration group, while feeding ability showed to decrease significantly at the lowest concentration group. The impact of feeding ability seems more sensitive than other targets. Moreover, we assessed the postexposure recovery of basic movements after the 4h exposure of Chlorpyrifos. Forward turn frequence of worms exposed to the highest concentration exposure failed to recovery, so that this suggested chlorpyrifos may have the long term health effect at high concentration exposure. Results also demonstrated that Caenorhabditis elegans could be a good model for chlorpyrifos-induced toxic effects research.