Environmental contaminants in breast milk from the central Asian republics

Abstract

Concern has been widespread about possible high levels of environmental contamination in areas of the former Soviet Union. Some of this concern has focussed on toxicants in human milk and their potential adverse effects on the breastfeeding child, but published data have been virtually unavailable. This study collected previously unpublished analyses of breast milk, water, cow's milk, and dairy product samples from several of the Republics during the last decade, providing an opportunity for comparing the level of contamination to similar data from other countries. The general levels of contamination are similar to those observed in other countries. Social and economic conditions as well as the contamination of water and substitute foods in the Republics make alternative methods of infant feeding demonstrably less desirable for the child than the measured levels of breast milk contamination.

PIP: Despite widespread concern about high levels of environmental contamination in the former Soviet Union, analyses of breast milk, water, cow's milk, and dairy product samples collected in the past decade from several areas of the Central Asia Republics revealed contamination levels comparable to those in other countries. Of particular concern were industrial and agricultural practices, including the use of pesticides, herbicides, and fertilizers, aimed at increasing productivity. DDT was present in a large portion of breast milk samples in Turkmenistan, Tajikistan, and Kazakhstan. The great range of concentrations of many toxic substances (10- to 20-fold) suggests exposures were from local rather than generalized sources. Seasonal variation in the percentage of positive samples was evident in both breast and cow's milk. Lacking, at present, are population-based studies of breast feeding practices (incidence, daily frequency, duration) in Russia that would enable estimates of the magnitude of infant exposures. For very stable, slowly metabolized, fat-soluble materials such as polychlorinated biphenyls and DDT, breast feeding may contribute disproportionately to an infant's exposure to environmental toxins. It cannot be assumed, however, that exposure will be decreased if infants are bottle fed. Breast feeding avoids exposing infants to bacteria-contaminated water and chemicals in substitute foods. In locales where maternal milk contains environmental toxicants, water and cow's milk are likely to be similarly contaminated. A policy to discourage breast feeding would increase fertility, infant mortality from diarrhea, and household expenditures. Public health professionals concerned about toxic exposure through breast milk should advocate for reduced environmental contamination for people of all ages.