Environmental Toxins and Breastfeeding

The Boston Herald recently published a story entitled “Tests show babies get doses of toxins in moms’ breast milk” by Kay Lazar (Tuesday, May 22, 2003), in which two women’s milk were analyzed and found to have toxins. The superiority of breastfeeding as the ideal feeding method for infants in their first year deserves added emphasis.

While this news implies that there may be harmful chemicals in the milk of some Massachusetts mothers, it is important to know that the greatest danger to babies from toxins comes from exposure during pregnancy. To protect our unborn babies, we must do everything we can to limit the harmful toxins in the environment. As Dr Schettler stated in the article, “breast milk monitoring is a way to measure what a baby was exposed to in the womb.” There may be other ways to assess prenatal toxin exposure: umbilical cord blood, for example.

Researchers looking for effects of toxin exposure through mothers’ milk have been able to find only benefits for breastfed babies, as opposed to formula-fed babies (e.g., Gladen et al, Journal of Pediatrics 1988; 133:991, Ribas-Fito et al, Pediatrics 2003; 111:e580.)

Infant formula, the only nutritionally appropriate substitute for human milk, is not a pure food — it is produced from cow’s milk or soy beans and many other substances that are grown or produced in the presence of chemicals. In fact, studies suggest that formula-fed infants may have a higher risk of certain cancers (Shu X-O et al, Int J Epidemiol. 1995; 24:27; Lucas A et al. Br Med J. 1990; 300:837). Further, since each mother’s milk is made to meet the needs of her particular infant, it is impossible for manufactured formula to duplicate the nutritional and immunological benefits of human milk.

The important findings noted in the Herald article should not frighten or discourage women who are currently nursing or pregnant. Our society must focus our attention on reducing toxins in the environment, which is the most effective way to protect babies and mothers from harm.

Kimberly G Lee, MD, MS, IBCLC
Associate Director, Newborn Nursery
Beth Israel Deaconess Medical Center, Boston

Cynthia Turner-Maffei, MA, IBCLC
Baby Friendly USA,
E. Sandwich, MA

(The above article is adapted from a letter to the Boston Herald by Dr. Kim Lee and
Cindy Turner-Maffei which was published on May 27, 2003)