Superfund Research Program
Early Life Exposure to Tetrachloroethylene (PCE)-Contaminated Drinking Water and Social Stressors may Interact to Increase the Risk of Substance Use Later in Life
This retrospective cohort study is testing the hypothesis that the perchloroethylene (PCE) found in public drinking water supplies in Cape Cod, Massachusetts is associated with reproductive and developmental disorders, including sperm and menstrual abnormalities, impaired fecundity, secondary infertility, spontaneous abortion, low birth weight, intrauterine growth retardation, pre-term delivery, congenital malformations, and developmental disorders of learning and attention. The study population is comprised of about 2,000 children and their families who were exposed to PCE-contaminated drinking water during 1969-1983 and a comparable group of 2,000 unexposed children and their families. Families were exposed to PCE when this solvent leached into drinking water from the inner vinyl lining of certain asbestos cement water distribution pipes. As described below, progress has occurred in the areas of subject identification and tracing, data collection, dose model development, and exposure validation.
To date, Dr. Aschengrau's team has identified 1,909 exposed children and randomly selected 1,854 unexposed children for the study population. All children were born from 1969 to 1983 in the eight Cape Cod towns where the PCE contamination occurred. Unexposed children have been frequency matched to exposed children on month and year of birth. Selection of study subjects will be completed when the numbers of exposed and unexposed children are equal.
Thus far, project investigators have traced 95% of the children's mothers or, if the mother is deceased, the children's fathers. They have also sent two batches of mail questionnaires to study mothers. The first batch (n=507) was sent in the spring of 2002, and the second batch (n=1,440) was sent in the fall of 2002. To date, responses have been received from 67% of mothers in the first batch and from 52% of mothers in the second batch. Reminder phone calls to non-respondent mothers are currently underway.
During the past year the investigators also developed and fine-tuned a dose model that incorporates the physical properties of PCE as well as behavioral information on bathing and water consumption. In addition, they began a validation study of the exposure assessment methods by comparing the results of the exposure assessment model to historical tap water sample test results. Both dose model and exposure validation study will improve the accuracy of the exposure assessments, and so will enhance the ability of the study to detect adverse health effects.