Libby MacDonald in—The Toxic Sandbox—a book and blog by the same name, questions the safety of breastfeeding by U.S. mothers, citing a 2003 study published in Environmental Health Perspectives that found high levels of flame retardant chemicals (PBDEs) in U.S. mother’s milk—levels reportedly 10-100 times higher than human tissue levels in Europe.

The presence of chemicals in human milk has also generated discussion on numerous blogs including Motherwear and BlogHer. Mary Brune was so concerned about breastmilk contamination, she launched a grass roots campaign—Moms Making Our Milk Safe—to raise awareness and promote community action. For more information see The Power of One. Most recently, Mary McDonough in Beauty and the Breast, cautioned mothers about the use of silicone breast implants stating, “it is by no means clear that the benefits outweigh the risks.”

Breastfeeding best in a toxic world
Despite these concerns, scientists currently recommend that women continue to breastfeed their babies, believing that the ‘known’ benefits of breastfeeding outweigh the ‘potential’ risks associated with toxic chemicals. The Environmental Working Group has suggested that breastfeeding may be even more important for mothers and babies exposed to environmental toxins:

“Careful study of babies’ toxic exposures indicates that it might be even more important for mothers who are concerned about their exposure to toxic chemicals to breastfeed their babies. Several long-term studies have followed groups of babies exposed to PCBs in-utero and found that the breastfed babies appear to be less impacted by the chemical exposures than their bottle-fed counterparts.”

Silicone breast implants
In 1992, the Food and Drug Administration (FDA) put a moratorium on the sale of silicone breast implants. The moratorium was lifted on November 17, 2006 when the FDA approved the use of silicone gel-filled breast implants for augmentation in women age 22 years and older, and for reconstruction in women of all ages. The FDA’s approval followed a period of extensive scientific review. Approval was given with the understanding that post-approval studies will continue to gather information about the safety and effectiveness of the implants.

According to Daniel Schultz, M.D. Director of the FDA’s Center for Devices and Radiological Health, “In the past decade, a number of independent studies have examined whether silicone gel-filled breast implants are associated with connective tissue disease or cancer. The studies, including a report by the Institute of Medicine, have concluded there is no convincing evidence that breast implants are associated with either of these diseases. However, these issues will be addressed further in the post-approval studies conducted by the companies.”

Silicone breast implants, reportedly, look and feel more natural and are less likely to ripple and/or rupture. Spear and colleagues followed 940 women with silicone breast implants for 6 years. (The sample will continue to be followed 4 more years as part of an FDA approved investigational study.) Results showed a rupture rate at 6 years of 3.5 percent. The most common local complication was capsular contracture, occurring in 15 to 20 percent of subjects. Satisfaction rates were uniformly high at 95 percent.

An obvious safety concern for younger women is how silicone breast implants will affect their ability to breastfeed and/or their breastfed babies. Can silicone leak from the implants? Can silicone get into the breastmilk? If so, can it harm the baby?

Researcher, John Semple, M.D., examined samples of blood and breastmilk from two groups of women, one group with and one without silicone breast implants. He found that the mean silicon (a proxy measure of silicone) level was not significantly different in the two groups. The results were published in the Supplement to the December 2007 issue of Plastic and Reconstructive Surgery. Interestingly, when silicon levels in alternative methods of infant nutrition were measured, including store-bought cow’s milk and commercially-available infant formulas, Semple found that the levels were much higher. Cow’s milk had a nearly 10-fold increase in silicon.

In addition, the Centers for Disease Control and Prevention and the American Academy of Pediatrics have concluded that, “there is insufficient evidence to justify classifying silicone implants as a contraindication to breastfeeding.

What’s a woman to do?
Ideally, it would be best for women to delay the use of implants until after their babies are no longer breastfeeding. This would avoid not only the ‘potential’ risks associated with toxic chemicals like silicone and platinum, but also the ‘known’ risks associated with breast surgery such as inadequate milk production. In the end, each woman must decide what is best, not only for her, but for her baby.

More information on breast implant surgery can be found at the Breastfeeding Cafe, the Mayo Clinic.com and the National Research Center for Women and Families.