Whenever I speak about health and the environment, I do so as both a biologist and a cancer activist. My diagnosis with bladder cancer at age 20 gives an urgency to my scientific research. Conversely, my Ph.D. in ecology informs my understanding of how and why I became a cancer patient in the first place: Bladder cancer is considered a quintessential environmental disease. But in writing about the effects of toxic materials on future generations, I add yet another identity––that of a mother.
After giving birth in September 1998 to my daughter and first child, I quickly learned what most parents learn about a kind of love that’s a deep physical craving like hunger or thirst. It’s the realization that you would lay down your life for this eight-pound person without a second thought. I say this to remind us all what is at stake. If we would die or kill for our children, wouldn’t we do anything within our power to keep toxics out of their food supply? Especially if we knew that, in fact, there were safe alternatives?
Of all food consumed by humans, breast milk is now the most contaminated. It is one rung higher on the food chain than the foods adults eat, so the toxic residues carried into mothers’ bodies become even more concentrated in the milk their breasts produce. To be specific, it’s about 10 to 20 times more contaminated with dioxins than cows’ milk. This is why a breast-fed infant receives its so-called "safe" lifetime limit of dioxin in the first six months of drinking breast milk. Studies have also shown that the dioxin in human breast milk declines steadily as nursing continues. The mother lowers her burden of carcinogens while increasing her child’s. Even thus compromised, however, breast milk is still a healthier food for babies than its inferior pretender, infant formula. This is why I have chosen to breast-feed my daughter for more than two years.
Let’s just look at the effects of one of the many toxic chemicals lurking in our environment, polyvinyl chloride plastics. The material is found in medical products, toys, food packaging, and vinyl siding. Sooner or later all of these products are tossed into the trash and, in many places, eventually incinerated. The dioxin created by burning PVC attaches to dust particles and raindrops and falls back to earth. It coats crops and other plants, which are eaten by cows, chickens, and hogs, or it rains into rivers and lakes and insinuates itself into fish. As a breast-feeding mother, I take in these molecules and distill them in my breast tissue. During this process, fat globules throughout my body are carried into the breast lobes, where a pituitary hormone called prolactin helps to turn the fat into milk. Another pituitary hormone, oxytocin, allows this milk to flow into the nipple, and to the back of the throat of my breast-feeding daughter.
This milk, my milk, contains dioxins from old vinyl siding, discarded window blinds, junked toys, used I.V. bags, and the plastic parts in burned-down buildings. This is an indisputable fact. What we scientists still debate is how the dioxin in mothers today will affect their breast-fed children. We don’t know because these kids are not old enough to display all the problems linked to dioxin exposure, which can include adult cancers.
We also know that breast-feeding has many benefits for the babies beyond almost perfect nutrition. Breast-feeding helps to develop a child’s immune system, which is why breast-fed infants have fewer bouts with infectious diseases than bottle-fed babies. In fact, the purpose of the clear and sticky milk a mother produces in the first few days after birth—colostrum—is almost all immunological. The mother then produces what is called transitional milk, which is very fatty and looks like liquid butter. Mature milk, which comes in about two weeks after birth, is the yellow-gray color of an old gray T-shirt. It contains elements that protect against diabetes, obesity, juvenile arthritis, and allergies. Children breast-fed as infants also score higher on intelligence tests, possibly because certain sugars unique to human milk help guide brain development.
Thus, we are just beginning to understand how breast milk contributes to babies’ healthy growth. We know less about the long-term health effects of dioxins and other toxins on newborns. If there was ever a need to invoke the precautionary principle—the idea that we must protect human life from possible toxic danger well in advance of scientific proof about that danger—it is here, in the breasts of nursing mothers. What is the price for the many benefits of breast milk? We don’t know yet. But why should there be any price? Breast-feeding should be a zero-risk activity.
My conclusion is that breast-feeding is a sacred act. To talk about the relative danger of breast-feeding versus bottle feeding, to weigh the known risks of infectious diseases against the possible risks of cancer, is an obscene discussion. A woman’s body is the first environment. If alternatives to PVC and other carcinogens exist, we have a moral obligation to use them. Compromising the goodness of breast milk is a human rights violation of the highest order.
Biologist and poet Sandra Steingraber is the author of Having Faith: An Ecologist’s Journey to Motherhood (Perseus Books, 2001). From Rachel’s Environment & Health News (July 11, 1999). Subscriptions: $25/yr. (42 issues) from Box 5036, Annapolis, MD 21403. This piece originally appeared in Protecting Public Health and the Environment: Implementing the Precautionary Principle, edited by Carolyn Raffensperger and Joel Tickner (Island Press, 1999).