This book focuses on exposure toxicology in C. elegans. The nematode Caenorhabditis elegans is sensitive to various environmental toxicants and stresses, and has proven to be an important animal model in both molecular and target-organ toxicology. As a result, over the past 30 years, there has been extensive research on the exposure to environmental toxicants or stresses in nematodes. Based on the available data, the book offers an introduction to the exposure system established in nematodes, discussing various aspects of endpoints that can potentially be used to assess the toxicity of environmental toxicants or stresses. Also exploring various factors affecting toxicity induction, and exposure to environmental toxicants and stresses, it allows readers to gain a systematic understanding of exposure toxicology in C. elegans.