This authored book presents basic immunological tenets and mechanisms at the cellular and molecular level while employing the toxicology focus on hazard identification, appropriate assays, dose response, and risk assesment by mathematical models and safety factors. It will be a useful reference to toxicologists because it will incorporate new guidelines that the EPA is bringing out later this year for all chemicals regulated under the Federal Insecticide, Fungicide, and Rodenticide Act and the Toxic Substances Control Act. Regulatory sections in each chapter focus on data from both the US Food and Drug Administration, as well as data applicable to western European Nations.