Journal Article

DDT and Breast Cancer in Young Women: New Data on the Significance of Age at Exposure

Piera M. Cirillo, Robert I. Sholtz, Cohn, Barbara A., Wolff, Mary S.

2007

Overview

Background: Previous studies of DDT and breast cancer assessed exposure later in life when the breast may not have been vulnerable, after most DDT had been eliminated, and after DDT had been banned. Objectives: We investigated whether DDT exposure in young women during the period of peak DDT use predicts breast cancer. Methods: We conducted a prospective, nested case-control study with a median time to diagnosis of 17 years using blood samples obtained from young women during 1959-1967. Subjects were members of the Child Health and Development Studies, Oakland, California, who provided blood samples 1-3 days after giving birth (mean age, 26 years). Cases (n = 129) developed breast cancer before the age of 50 years. Controls (n = 129) were matched to cases on birth year. Serum was assayed for p,p'-DDT, the active ingredient of DDT; o,p'-DDT, a low concentration contaminant; and p,p'-DDE, the most abundant p,p'-DDT metabolite. Results: High levels of serum p,p'-DDT predicted a statistically significant 5-fold increased risk of breast cancer among women who were born after 1931. These women were under 14 years of age in 1945, when DDT came into widespread use, and mostly under 20 years as DDT use peaked. Women who were not exposed to p,p'-DDT before 14 years of age showed no association between p,p'-DDT and breast cancer (p = 0.02 for difference by age). Conclusions: Exposure to p,p'-DDT early in life may increase breast cancer risk. Many U.S. women heavily exposed to DDT in childhood have not yet reached 50 years of age. The public health significance of DDT exposure in early life may be large.

• Publisher: National Institute of Environmental Health Sciences. National Institutes of Health. Department of Health, Education and Welfare,National Institute of Environmental Health Sciences
• Subject: Adult / Age Factors / Age factors in disease / Age groups / Biological markers / Blood / Body mass index / Breast cancer / Breast Neoplasms - epidemiology / California - epidemiology / Cancer / Carcinogens, Environmental - adverse effects / Carcinogens, Environmental - analysis / Case-Control Studies / Contaminants / DDE / DDT (Insecticide) / DDT - adverse effects / DDT - blood / Dichlorodiphenyl Dichloroethylene - blood / Environmental Exposure - adverse effects / Environmental health / Evaluation / Exposure / Female / Health aspects / Health risks / Humans / Metabolites / Middle Aged / Nitrous oxide / Oncology, Experimental / Polychlorinated biphenyls / Predisposing factors / Pregnancy / Prospective Studies / Public health / Risk factors / United States - epidemiology