The book introduces the basics of toxicology from a risk assessment perspective, using a jargon-free, journalistic style that makes scientific concepts accessible to a wide audience without "dumbing down" the science. It covers the fate and transport of chemicals in the environment, dose-effect, animal toxicity testing, human epidemiology, the uptake, distribution, and elimination of toxic chemicals including first-order rate constants and calculations of body burdens, and the cellular basis of cancer and other diseases that can be caused by toxic chemicals. The book also introduces risk management and discusses the balance between precaution and socio-economic benefits, as embodied by the Toxic Substances Control Act, the Canadian Environmental Protection Act, and the European Union’s innovative REACH directive (Registration, Evaluation, Authorization, and Restriction of chemicals). Putting equal emphasis on the twin issues of risk assessment and risk management, the author has carefully selected topics that shed light on risk management decisions and cover ecotoxicolocy and organismic toxicology. The book provides a thorough introduction to the science of toxicology and to the policy debates and scientific uncertainties that make risk management a work in progress.