Most public controversies about the effects of chemicals on human health revolve around the risk of cancer?hardly surprising, considering that it is the second leading cause of death in the United States. People are concerned about the dangers of carcinogens in air, water, and food, and they expect their representatives in government to protect them from such hazards. On the other hand, the economic costs of eliminating every suspected carcinogen from the environment would cause tremendous economic hardship. How should policymakers use science to help strike a balance between the benefits of lowering the risk of cancer and the economic costs of regulation? In this important book the authors squarely address the complex interaction of science and regulatory policy. They begin by clarifying the scientific issues that are central to regulatory decisions, then explain how and why scientists can honestly disagree about these issues. They demonstrate with two cogent case studies: the heated debates about formaldehyde and benzene, both useful but potentially toxic chemicals. By examining how scientists evaluated the risks from these chemicals, and what kinds of legislative, administrative, and judicial decisions emerged from the evaluations, the authors furnish insight into the checks and balances of health-risk regulation. They point out that overselling science in this context is harmful to both science and democracy. Their final chapter proposes creative methods for constructing a bridge between the scientist and the regulator that will be invaluable to anyone concerned about health risks.