awareness that reporting and publication biases can distort the sample of studies available for pooling.
Chapter 2 discusses how federal and state environmental policies have largely shaped the development of environmental epidemiology as it pertains to the study of hazardous-waste sites in the U.S. First, scientists working for state and federal agencies perform most of such studies. Second, federal and state regulations determine the nature and limitations of available data on environmental contamination related to hazardous-waste sites. Third, federal and state agencies are continuously involved in the process of defining which chemicals found in the environment are of concern for human health and the levels at which action should be taken to protect human health.
The legislation that produced these state and federal programs was clearly intended to protect human health. Congress and the states enacted the legislation which created Superfund in the early 1980s in response to public concern about the effect of hazardous-waste sites on the health of nearby communities—concerns that persisted and escalated through the decade as the dimensions of the problem continued to expand. ATSDR was also established by this legislation to provide health assessments and other relevant information on hazardous-waste sites. These programs have not allayed public concerns. Public opinion surveys consistently rank hazardous-waste sites among the most serious environmental risks and the environment as an issue of great public concern. Hazardous-waste sites are a major public health management issue in every state. Half of the U.S. population and 95 percent of the rural population relies on ground-water as the main source of drinking water. Each year thousands of wells are closed because of hazardous-waste contamination. According to a number of polls, the public fears hazardous waste, wants it cleaned up, and is willing to pay the enormous sums currently spent on Superfund because of the belief that this program will protect public health.
Chapter 2 questions how so much effort and money could have been spent with such a moderate yield in knowledge. It reviews federal and state legislation, policies, and programs that determine how hazardous-waste sites are evaluated; what information on exposure and health effects is collected; how the data are analyzed and used in setting priorities and planning remediation programs; and what proportion of hazardous-waste-control budgets is spent on as-