Each day we are exposed to a myriad of natural and human-made chemicals in our food, drinking water, air, soil, at home or at the workplace--pesticide residues, food additives, drugs, household products--but how can we gauge the human health risk posed by these chemicals? Should we believe the somber headlines that depict a serious threat for humans and the environment, or should we follow the reassuring voices of others who claim that the angst is totally unfounded? Why the Dose Matters: Assessing the Health Risk of Exposure to Toxicants uses a rational, science-based approach to explain in plain language that a quantitative view is key for understanding and predicting potentially toxic effects of chemicals. Key Features: Explains the basics of toxicology in easily understandable terms Includes numerous examples Clears up common misconceptions and dispels myths Provides take-home messages for each chapter Discusses natural and synthetic chemicals, such as pesticides, wood smoke, mercury, and more This book is aimed at interested laypeople. It uses numerous examples to illustrate the basic concepts and ensure that the reader will get a better understanding of why not only the hazard, but also the overall exposure will determine whether some chemicals pose a serious risk while others are of little or negligible concern.