Who's Exaggerating?

It ought to be the best of times for someone like me. I’m a professional risk assessor--the director of health standards at the U.S. Occupational Safety and Health Administration (OSHA)--and risk assessors are much in demand these days. One reason is that the nature of the health and environmental hazards we face has changed. When rivers were bursting into flame, as Cleveland’s Cuyahoga River did in 1969, or when smog was so bad it made your eyes tear, we didn’t need elaborate risk assessments to tell us something had to be done. The newer generation of environmental threats are different: they’re often no less serious, but they’re harder to measure and harder to eliminate. When toxic chemicals leak onto an open field for decades, and a neighborhood grows up around that field, and some of the chemicals seem to be reaching groundwater used for drinking, should the field be cleaned ...