To answer the question of whether science and technology are adequately providing safe drinking water we should first understand the risks that drinking water may carry, noted Jeffrey Griffiths, Tufts University School of Medicine. Some of them are related to the population, which is not only growing in size but changing in its characteristics—particularly with respect to enhanced sensitivity to waterborne contaminants. Thus, at the same time that water must be reused—given the growing demand—there is additional pressure to ensure that the drinking water remain at levels of acceptable public health protection. Meanwhile, the changing activities and increasingly concentrated locations both of people and of industries result in significant levels of new emerging contaminants. These, together with agents already well established in the inventory, confront us with approximately three million potential chemical contaminants—that calls for paradigm shifts in the ways we think about these issues, suggested Griffiths.
There are many interfaces between the science and the policy of the Safe Drinking Water Act (SDWA), according to Frederick Pontius, president of Pontius Water Consultants, Inc. In fact, the policy and current provisions of the SDWA grew out of our prior failures and scientific advances. There are the legal mandates and requirements that control options, exposures, dose-response relationships, costs and benefits, laboratory methods, and agency processes. The SDWA is a mixture of different lines of reasoning, different facts, different assumptions, and different judgments made by people with different perspectives. Such decision making cannot be based on science alone and requires a blending of science and policy in order to achieve the necessary end points, noted Pontius. Scientists are struggling with data gaps across all aspects of regulation from how to select contaminants to the establishment of health goals. Further challenges for maintaining the use of the best science include filling data gaps and ensuring high-quality peer reviews so that future and revised drinking water regulations are based on the best available science.