Columbia Population Research Center

Every year, millions of pounds of toxic chemicals thought to be linked to developmental problems in fetuses and young children are released into the air. In this paper we estimate the effect of these releases on the health of newborns. Using data from the Toxic Release Inventory Program and Vital Statistics Natality and Mortality files, we find significant negative effects of prenatal exposure to toxicants on gestation and birth weight. We also find that several developmental chemicals increase the probability of infant death. The effect is quite sizeable: the reported reductions in cadmium, toluene, and epichlorohydrin releases during the 90s could account for about 3.9 percent of the overall decrease in infant mortality. Our results are robust to several specification checks, such as comparing developmental to non-developmental chemicals, and fugitive air releases to stack air releases. * Department of Economics, Columbia University, 420 W 118 St., New York, NY 10025, [email protected], and [email protected]. The authors thank Alan Burke for excellent research assistance. We also thank Alan McCartland and participants in seminars at Berkeley, Columbia, and the International Health Economics Associations meetings in Copenhagen in June 2007 for helpful comments. This research was supported by funding from NIH R21 HD055613-01. We are solely responsible for all errors. Every year, millions of pounds of toxic chemicals thought to be linked to developmental problems in fetuses are released into the air. Yet, we have only limited information about the health effects of these releases. A 1998 Environmental Protection Agency (EPA) review found that complete screening data about toxicity was available for only 7 percent of 3,000 chemicals released in large quantities in the U.S. (U.S. EPA, 1998). Even for chemicals that have been studied, there is little information about how levels found in the environment affect human health. Laboratory data on toxicity may be of limited value given that tests are typically conducted on animals, and do not take human behaviors (such as staying inside on high pollution days) into account. Moreover, it is quite difficult to draw a relationship between a disease such as cancer and toxic exposures in a particular location given that cancer develops over a long period, and people are mobile. In contrast, birth outcomes are likely to be highly affected by conditions during the brief interval of pregnancy (though of course they might also be influenced by factors affecting the mother before conception). Hence, infant health outcomes are an ideal place to look to see if existing environmental releases have detectable negative effects for human health. This study uses data from the EPA’s Toxics Release Inventory (TRI) matched to data from national Vital Statistics Natality and Mortality files to examine the effects of fetal exposure on health at birth and subsequent infant mortality. Exposure to toxic chemicals may be linked to many other characteristics of families and neighborhoods, and to swings in economic activity. In an effort to identify the effect of toxic exposures, we compare the estimated effects of chemicals that are thought to be developmental toxicants to those which are not known to have developmental effects. We also compare the effects of “fugitive” air releases to the effects of “stack” air releases. Emissions that go up a smoke stack are more likely to be treated in some fashion