Chapter One

Environmental risk analysis for human health is a systematic analytical process for assessing, managing, and communicating the risk to human health from contaminants released to or contained in the environment in which humans live. Environmental risk analysis encompasses a broad variety of disciplines and endeavors, including natural sciences such as geology, meteorology, hydrology, and ecology, which describe the natural environment in which contaminants migrate; biological sciences such as physiology, toxicology, anatomy, and cell biology, which describe the interaction and response of humans to environmental toxins; physical sciences such as physics and chemistry, which describe how contaminants migrate in natural systems; and decision and social sciences, which provide methods for making rational decisions and for communicating with stakeholders throughout the risk analysis process.

A well-established paradigm for risk analysis is that it is comprised of (1) risk assessment, (2) risk management, and (3) risk communication (ACS 1998). Most of this book addresses the environmental risk assessment component of environmental risk analysis. However, most environmental risk assessments are performed to answer a question or resolve an issue, such as: Is it safe for a proposed chemical plant to operate in this location? Because the issue drives the scope, depth, technical content, cost, and schedule of the risk assessment, we also address the risk management and risk communication components of environmental risk analysis.

Much of the material presented in Chapters 2 through 11 is in the form of determ