Chemistry and controversy: the regulation of environmental chromium

The regulation of chromium in drinking water and sludge illustrates some of the challenges of regulating a chemical with complex environmental chemistry in a dynamic regulatory environment. The controversies evoked in setting environmental standards for chromium reflect technical uncertainties and the conflicting values of affected parties including regulators, citizens potentially exposed to chromium pollution, polluting industries, and research scientists. Regulatory limits for chromium in water and sludge recognize the paradoxical nature of chromium chemistry but also illustrate how the use of risk assessment can alter the regulatory approach. The framework of rationality as described by Crawford-Brown is suggested as a useful tool for evaluating regulatory limits for environmental contaminants. Science-based policies are most rational when they reflect the characteristics of rationality with respect to the ends or objectives sought, the means chosen to achieve these ends, and the beliefs that substantiate the chosen means and ends. If scientific research is to be applied to regulatory or environmental policy questions, then the traditional focus on the rationality of empirically based scientific beliefs must be expanded to consider the focus of the research question and the methodologies used.