American Scientist

Environmental Cancer: A Political Disease? S. Robert Lichter and Stanley Rothman. 208 pp. Yale University Press, 1999. $17 (paper).

The Polar Bear Strategy: Reflections on Risk in Modern Life. John F. Ross. 208 pp. Perseus Books, 1999. $23.

Health alerts are never far from public consciousness. Although the Alar scare may be fading from memory, periodic E. coli and Listeria outbreaks, recent widespread recall of dioxin-contaminated poultry and beef products and children sickened by tainted cola in several Western Europe countries serve to remind us of the need for vigilance about food safety, ironically at a time when our food supply, our rivers and our air are arguably cleaner than at any time since the Industrial Revolution. Thus the two books reviewed here are especially timely. Both speak to the subject of risk, focusing especially on risk from environmental exposures. Both seek to compare reality, as best we can assess it rationally, with the public perception of hazards. Both differ tremendously in approach and style, hence in readability and ultimately in their ability to deliver their messages.

Risk assessment, risk analysis and risk communication as disciplines have risen to prominence since the immediate post-World War II view of science and technology as the fount of great social advances has been replaced by widespread public skepticism in an increasingly risk-averse society. Publication of Rachel Carson's Silent Spring raised awareness of the adverse environmental consequences of rampant industrialization; triumph over the first moon landings gave way to dismay at the Challenger explosion; vaccines turned from being miraculous weapons against disease to vehicles for often lethal side effects. Meanwhile, legislation passed from the early 1970s onward has curbed the most egregious discharges into the environment so that average blood lead levels have dropped, cigarette smoke is virtually absent from public places, pelican and eagle populations endangered by pesticide residues are recovering and the Cuyahoga River no longer bursts into flames from its burden of industrial solvents.

Risk analysis of course has long been a mainstay of the insurance business; indeed that entire industry depends on the accuracy of its predictions of outcomes, be they the duration of a life or the completion of a sea journey without shipwreck. Formal risk assessment in the environmental context rose to prominence in response to the above-mentioned legislation, which mandated that pollutants in ambient air, residues in food and contaminants in drinking water be limited to levels that posed "no appreciable risk" to health. The National Research Council in 1983 formulated an outline intended to harmonize the risk-assessment process across all agencies of the Federal Government. The "Red Book" (Risk Assessment in the Federal Government: Managing the Process), focusing on chemical agents, delineates four steps. The first three—hazard identification, exposure assessment and dose-response assessment—cover identification of a hazardous agent, evaluation of the circumstances and levels for which a target organism is exposed and the magnitude of damage after a given exposure. The fourth step, risk characterization, integrates the scientific information thus derived into an expression of the likelihood (or risk) of adverse outcome for a given exposure scenario. These four steps, or their equivalents, reappear in more recent attempts to develop procedures applicable to microbial agents and to hazards to ecological systems, where the unit at risk is not so much the individual organism as entire populations or the ecosystem as a whole. The aspect of this process that is of immediate concern, to toxicologists and regulators alike, is the quantitative determination of levels of exposure that can be considered "safe" or "virtually safe."

What has become increasingly apparent is that the process does not stop there; effective communication of the significance of such levels to regulators, legislators and the general public (risk communication) and the development of rational and scientifically defensible procedures to inform public policy and achieve "safe" exposure levels (risk management) have been recognized as essential components and have acquired much more prominence of late. Other important developments include the increasing level of interest and involvement of industry, concerned with costs associated with remediative action, of special interest groups, of environmental and social activists and of journalists.

Environmental Cancer: A Political Disease attacks that last issue head-on. Following introductory material on the history and current status of environmentalism and the multitude of diverse groups that collectively make up what is loosely termed the environmental movement, and a chapter on the biology, causes and medical aspects of cancer, the book focuses on the different groups with a vested interest in the environmental risk-assessment process and on the dollars (taxpayers' or business income) at stake. The meat of this book consists of scholarly analysis of two surveys, conducted over a 20-year span. One survey addresses contrasting opinions and attitudes of cancer specialists and environmental activists over the environmental causes of cancer. The other focuses on media coverage of environmental cancer, seeking to tease out the relative levels of confidence of cancer specialists and environmental activists in different information sources and assess the impact of journalistic coverage on public perception of environmental hazards. There is much information here that is of use to those particularly interested or actually working in this general area. As befits a sociology study, the book is replete with graphs, charts, tables and footnotes. The authors do take pains to maintain impartiality. Nevertheless, the cancer researchers come across as hard-headed realists, the environmental activists as ideologues and the media as opportunists who sensationalize whatever falls into their grip. Most telling, however, are the authors' concluding remarks, which place the vulnerability of scientific facts to manipulation by interest groups firmly in the context of the generally poor level of scientific understanding evident among the American public.

The Polar Bear Strategy, if widely read, might actually contribute to raising that level of scientific understanding. Although there is not a table or chart in sight, the text conveys a richness of information on environmental and other health hazards packaged in a way that is immediately accessible to the general reader. The author starts from an anecdote, a personal encounter with polar bear footprints during the course of a canoe and camping trip in Alaska. The ensuing debates among the small group of travelers as to the appropriate strategic course of action should they be attacked by the bear—whose proximity they infer from the footprints—provide the framework for a series of essays on different aspects of risk and risk management in everyday life. Some of this material in fact covers the same ground as the previous book: differing perceptions of risk between the general public and the "experts," overblown media coverage, the impact of ideological and personal bias. Substantive statements are also documented with a bibliography and appropriately indexed. This book offers an exposition of the scientific context that is both accurate and informative to the nonspecialist. The chapter "An Eccentric French Monk Lauches a Revolution" presents the most lucid introduction to the statistical analyses fundamental to epidemiology and risk analysis that I have ever read. The chapter also suggests the possibility that Blaise Pascal and other giants in the field were actually flesh-and-blood human beings. The author makes no attempts to conceal his own opinions, which in the main reflect robust common sense. He does not hesitate to skewer the excesses of bureaucrats and activists alike. This is the book that I would offer to a student, from high school to graduate, who is considering environmental sciences or management as a career. I would suggest that my mother read this if she were interested in the wider context of my own work.

The travelers, not surprisingly, do nothing and live to tell the tale. But we never do find out about the polar bear's own strategy. Maybe he (or she) decided that with average tissue dioxin levels at or above the World Health Organization–recommended limit in food, humans are just not fit for consumption.