The Environmental Protection Agency (“EPA”) is requiring the monitoring of drinking water supplies for a variety of heretofore unmonitored chemicals (e.g., hexavalent chromium, perfluorooctanic acid (PFOA), 1,4 dioxane, various volatile organic chemicals (VOCs) (such as 1,1 dichloroethane), and various hormones (such as 17-β-estradiol)). This may assist in prioritizing which chemicals should be subject to new drinking water standards, but the low detection limits utilized are likely to lead to broader regulatory scrutiny of such chemicals. It is likely that many (if not all) of these chemicals will be detected in surface water and ground water, albeit at very low ubiquitous background levels. As noted during this year’s National Academies of Science’s Abel Wolman Distinguished Lecture Series: “[i]ncreasingly, we know a chemical is present in drinking water without understanding what it means.”
Some stakeholders favor taking action to be “safe rather than sorry” (i.e., taking action before we know what the levels mean). Other stakeholders advocate improving and expediting the existing risk assessment process, but without abandoning underlying traditional risk assessment principles. The public may misinterpret the mere presence of the chemical with a significant risk, particularly when there are no federal drinking water standards (as is the case for all unregulated contaminants). Regulatory initiatives may involve not just the issuance of new drinking water standards, but re-consideration of the uses of these chemicals in commerce.
Companies which make these chemicals or products containing these chemicals may want to track regulatory developments involving them and comment, if appropriate. Some companies may even decide to make their products more “sustainable” by eliminating these constituents, even before there is a quantitative risk assessment demonstrating an unacceptable risk. Others may begin evaluating internally (prior to regulatory action) whether there are cost-effective substitutes. Thus, the mere act of monitoring unregulated chemicals in drinking water may have unintended and broader societal consequences. In the absence of a scientific consensus concerning how to address chemicals present at levels below our capability to understand their effects, interpreting the results of such monitoring will be difficult and controversial.