change; 3) water quality and nutrient pollution; and 4) shifting spatial and temporal scales. The chapter ends with a section on, “Using New Science to Drive Safer Technologies and Products”, which discusses ways in which EPA can prevent environmental problems before they arise.
The examples in this chapter are not intended to be comprehensive; rather, they are provided to illustrate from different perspectives the many ways in which new advances in science, engineering, and technology could be embraced by the agency, its scientists, and regulators to ensure that the agency remains at the leading edge of science-informed regulatory policy to protect human health and the environment. Having assessed EPA’s current activities, the committee notes that EPA is well equipped to take advantage of most of the new scientific and technologic advances and that, in fact, its scientists and engineers are leaders in some fields.
New technologies will be important to EPA for identifying chemicals in the environment, understanding their transport and fate in the environment, assessing the extent of actual human exposures through biomonitoring, and identifying and predicting the potential toxic effects of chemicals. Current and emerging tools and technologies related to these topics are discussed in the sections below.
Identifying Chemicals in Environmental Media
Analytic chemistry continues to improve at breakneck speed, and analytic determinations for both metals and organic chemicals have improved exponentially. Chemicals can now be detected at ever lower concentrations. For some organic chemicals, such as chlorinated dioxins, standard EPA methods include the routine measurement of samples in parts per quadrillion (ppq) or picograms per liter (pg/L) (EPA 1997), which allows risk managers to characterize lifetime uptake of exposure to various carcinogens and daily uptake rates in chronic hazard quotient assessments of chemicals that were not previously detectable. Simply being able to measure concentrations of chemicals in environmental media or blood confronts EPA with new decisions on whether to set maximum contaminant levels in drinking water or allowable daily intakes in food or whether to allow states to do so independently if health effects are uncertain.
As the public learns about new methods of detection of chemicals in, for example, their blood, their children’s blood, and the environment (water, air, and soil), questions arise as to what such occurrences mean. Of course, the simple detection of chemicals in relevant receptors does not necessarily imply any human health or ecologic effects. To evaluate the health implications of chemical