the committee finds that this question cannot be answered. One recent EPA survey found that more than 40 million people live within four miles of a Superfund site. Residential proximity does not per se mean that exposures and health risks are occurring, but the potential for exposure is increased.
National decisions to clean up hazardous-waste sites have been made independently of studies about the overall impact such sites may have on public health. During the past 10 years, less than 1 percent of the estimated $4.2 billion spent each year on hazardous-waste sites in the U.S. has been used to evaluate health risks at listed Superfund sites. As a result, existing data on exposures and health effects are inadequate either to support decisions on the management of hazardous-waste sites or to allow the conduct of epidemiologic investigations of the health impact of these sites. However, recent efforts by the Agency for Toxic Substances and Disease Registry (ATSDR) and EPA have improved the information base and should be further extended.
Although billions of dollars have been spent during the past decade to study and manage hazardous-waste sites in the U.S., an insignificant portion has been devoted to the evaluation of attendant health risks. For that reason and because of technical obstacles, information about the connection between exposures from hazardous-waste sites and health effects remains inadequate.
This chapter draws on the preceding ones and recapitulates the committee 's major findings about the epidemiologic study of hazardous-waste sites. Despite the lack of adequate data with which to characterize the effects of hazardous wastes on public health in general, the committee concludes that exposures from hazardous-waste sites have produced serious health effects in some populations. Table 1-1 summarizes the peer-reviewed literature on this subject. A limited number of epidemiologic studies indicate that increased rates of birth defects, spontaneous abortion, neurologic impairment, and cancer have occurred in some residential populations exposed to hazardous wastes. We are concerned that other populations at risk might not have been adequately identified.
To improve the ability to evaluate health effects associated with exposures to hazardous wastes, a number of important data gaps need to be filled and several resource constraints need to be remedied, as this report illustrates. There is a need to make health assessments a priority in the routine evaluation of hazardous-waste sites. There is also a need to create mechanisms for sharing this information as well as information from epidemiologic investigations of these sites nationwide. Accordingly, state and local health department investigations of hazardous-waste sites must be adequately sup-