Introduction

Introduction

The Agency for Toxic Substances and Disease Registry (ATSDR) has a broadly defined legislative mandate to prevent or mitigate adverse human health effects and diminished quality of life resulting from exposure to hazardous substances in the environment. Population-based research conducted to identify links between exposures and specific adverse health effects is a necessary part of this mandate. One exposure-disease relationship that warrants further investigation is the association between volatile organic compounds (VOCs) in drinking water and adverse pregnancy outcomes. Pregnancy outcomes are of particular importance to populations residing on military bases because such populations include a high proportion of reproductive-aged individuals.

Objectives

The primary objective of this retrospective study was to explore potential associations between previous exposure to VOCs in drinking water and three adverse pregnancy outcomes at the U.S. Marine Corps Base at Camp Lejeune, Onslow County, North Carolina, where tetrachloroethylene (PCE), trichloroethylene (TCE), and 1,2-dichloroethylene (1,2-DCE) were found in drinking water supplies in the 1980s. The three pregnancy outcomes were (1) reduced fetal growth, measured as decreased mean birth weight (MBW) and small for gestational age (SGA); (2) preterm birth; and (3) late fetal deaths. However, because of incomplete data, this third outcome could not be determined.

Three secondary objectives of the study were (1) to validate the quality of housing record information as it was used to assign exposure and duration of exposure (see Appendix A); (2) to evaluate the feasibility and utility of reviewing medical records to enhance the study's inferences (see Appendix B); and (3) to gather existing information on birth defects (see Appendix B). It was understood from the outset that the third and final objective would be difficult to achieve because of the limited information regarding birth defects available from birth certificates. Nonetheless, the potential relationship between VOCs and birth defects is of such strong public health concern that an attempt was made to evaluate all existing data.