In honor of Breast Cancer Awareness month, Moms Clean Air Force sat down recently with Florence Williams, author of the book, BREASTS: A Natural and Unnatural History, a compelling, scientific exploration of this unique organ. Did you know that a women's breasts are not fully developed until the third trimester of her pregnancy, when her mammary glands finally mature? That breasts are the second most common site of tumors in the human body, next to the skin? That breasts fine-tune milk production to the appetites, age and even the specific sex of the infant they are feeding? Williams, a journalist and mom, goes on a very personal journey to learn more about how and why toxic chemicals ended up in her breast milk. In the process she shows us how breasts have evolved specifically to absorb the chemical cues from the surrounding environment -- which may have grave health implications for us and our daughters.
Why did you write a book about breasts?
I first got interested in this topic after my daughter was born. I was reading reports that there were industrial chemicals in breast milk. I had never really thought much about my breasts before I became a mother, but then they sort of amazed me, what they were capable of. When I found out about this research, I thought it would be interesting to tell that story using my own breast milk. So I sent it to a lab in Germany, which at the time, was one of the few places in the world where you could do these tests. It came back positive for trace amounts of a pesticide, and slightly above average levels of flame retardants. Then I set out on this journey to find out what that meant, for my health and for my daughter's health.
From there, I became really interested in the field of environmental health, and learning how our bodies are kind of permeable. The way we treat our environment gets reflected back in our own cells.
Breasts are very sensitive to the environment at every single life stage, from earliest embryonic development through puberty and pregnancy and lactation and menopause. So it turns out that they're really sentinel organs in our bodies.
You write that breastfeeding is an "ecological act." What do you mean by that?
I have to admit I borrowed that phrase from Sandra Steingraber. She is one of my idols. It's an "ecological act" because our breasts so deeply connect us to the world around us. What appears in our breast milk is a mirror of our industrial life. I think it's important to say that I continued breastfeeding, because some people have misinterpreted my saying there are chemicals in breast milk to mean I don't advocate breastfeeding. But I did continue breastfeeding and I don't have any regrets about it.
Tell me more about the contaminants in your breast milk. What were they, and how did they get there?
The largest source of flame retardants in our bodies is dust in our homes. Many of the things in our homes are filled with flame retardants, from our upholstered furnishings to carpet padding to thermoplastics, like the casings of our TV sets and computers. We are exposed to the dust through inhalation and probably ingestion and even dermal contact. It also means I'm maybe a bad housekeeper!
But really, we all have these compounds in our homes. And if we're worried about our breast milk having it, we should also be worried about our babies crawling around in it, whether they're breastfed or not. For them, breast milk is just one exposure.
What are the health effects of flame retardants?
They are largely unknown. The studies that have been done are mostly in lab animals. In those animals there is some indication that they interfere mostly with thyroid hormones. The thyroid is very important for regulating other hormones. There's also some indication that these chemicals may be neurotoxins, and may interfere with brain development. In the epidemiological studies, there have been some associations with thyroid problems, and with infertility. The good news is that the PBDEs are being phased out of furnishings. But they're being replaced with other flame retardants that act very similarly.
These chemicals are so bioavailable, yet we know so little about their toxicity. And I don't think it should be my responsibility as a mother to filter out every substance in my home. It really should be the government's responsibility -- and the responsibility of the manufacturers to use safe chemicals in the first place.
What else did you find in your body?
At a different lab in Texas I tested again and found low levels of perchlorate, which is an ingredient sometimes found in jet fuel, so that was kind of disturbing. Again, we don't really know what it does to our infants or to our breast tissue. And then for the book, my daughter and I did some other testing of our urine for a number of other household chemicals that we're exposed to all the time: BPA, phthalates, triclosan, parabens. Then we did an experiment to see if we could reduce our levels by changing our lifestyle habits, just for a few days. I became a vegan for a few days, and I didn't use any scented personal care products. I tried not to eat food that had even come into contact with plastic. I didn't ride in my car because we know that car interiors emit phthalates.
I was able to reduce my levels in my urine by up to 80% for a lot of these substances. But what really surprised me was that there were some chemicals that I couldn't really budge at all. Those were mostly the phthalates, which are used to soften plastics, and they are also used in things like nail polish, paint thinners, printing cartridges and PVC shower curtains.
What are the health concerns with that class of chemicals?
Some of the phthalates have been associated in both animal studies and epidemiological studies with increased feminization among boys. Phthalates are endocrine disruptors.
If you were to test American women generally, would you be finding the same things?
Yes. The chemicals found in my body are commonly found in the vast majority of American men and women. [Many] Americans have been found to have BPA, for example, in their bloodstreams. So I felt sort of helpless. There were some things in my environment I could control through lifestyle and consumer choices, but there were other things I had no control over. To control them, I had to take fairly extreme lifestyle measures. There are studies showing that the Amish have much lower levels of these chemicals. So basically we would have to all live like the Amish, which isn't very practical.
Did this lead to changes in your personal life?
It did lead to some. I feel like the impact is sort of superficial. Because really we are not going to be able to have a big impact until we change the way products are made. But there are some things I do. I often pack my kids' lunches in cloth or in glass -- but again it's a little bit futile because I pull the carrots out of the plastic bag in the fridge.
What did you learn about breast cancer?
I learned that breast cancer is an incredibly complex disease that seems to have many factors contributing to it, some of which are environmental -- and I'm including pharmaceuticals in that category. For example, women who take Hormone Replacement Therapy are at a higher risk of breast cancer. And many studies have shown that women who take birth control pills, especially the higher dose ones from several decades ago, seem to be at higher risk.
We know that there are many substances in our environment, some of which are pharmaceutical but some of which are industrial, that are estrogenic. So that is a logical place to look for possible breast cancer associations. There have been some intriguing findings. Women who were exposed to DDT as girls are at higher risk for breast cancer later on. The timing around puberty is a really vulnerable time for us in terms of exposure to carcinogens. We know that's true of X-rays and radiation, and now we see it with some pesticides.
Some industrial chemicals have a multigenerational effect. When you expose a pregnant mouse to BPA, it alters the development of the mammary gland in her offspring. We've seen this in humans too with DES, which is a drug that was given to pregnant women for several decades before 1970. The daughters of those women given the drug are at higher risk for breast cancer as well as reproductive deformities, and their daughters now are also showing a higher rate of breast cancer. So we are seeing three generations so far of the effects of DES.
These breast cancer studies I would say are full of caveats. We need to have more studies and we need to be testing chemicals actually on mammary glands. Typically when chemicals are tested, even the few that are tested by our government, they are not actually looking at effects of mammary glands. They're looking at effects on the liver and the heart and the brain. And those are all good endpoints to look at, but we know that the mammary gland is one of the most sensitive organs we have. It is the most common site for tumors in the body.
A lot of women agree that we have spent a lot of money on breast cancer studying the wrong things. We have put so much money into screening and treatment, and those are really important, but by the time you catch a breast cancer tumor on a mammogram, it's too late. She already has the tumor. We need to prevent those tumors from growing in the first place.
What is happening with puberty?
The scientific consensus now seems to be after much discussion and controversy that breasts are developing younger in girls. To some degree this is biologically expected because girls are healthier now, and they have better nutrition, than they did before the industrial revolution. But the age of puberty is falling faster than it should be, faster than you would expect. Even since the 1970s it has fallen, and certainly infections and nutrition haven't changed that much since then. Now one thing that has changed is rates of obesity. And it looks like there is some link between the age of puberty and body fat. But that also doesn't seem to be explaining the entire phenomenon, so researchers are looking harder at other factors, some of which are social. For example, rates of divorce seem to affect age of puberty, and how much exercise girls get, and how much fiber they get. But scientists are also looking at these estrogenic chemicals in their diets and their households.
Give me an example of what those are.
There are about 16 different chemicals being looked at really closely by federal researchers right now. They include products of cigarette smoke, products from pesticides, flame retardants and additives in personal care products like parabens (a preservative), triclosan (a microbicide), phthalates (plastic additives), and BPA (also a plastic additive).
What are you doing to protect your daughter?
I don't want to be one of those mothers who is constantly taking away sources of joy for their children. But I do try to limit her access to things like toenail polish. I'm not going to say that she can never do it, but I'm not that psyched if she wants to do it all the time. So it's a special occasion kind of thing. Also, it really makes sense to have your kids wash their hands before they eat, because they are exposed to this house dust that likely has industrial chemicals in it.
What should moms be doing about all of this?
I think that moms can be a really powerful group for change. When we found DDT in breast milk, that's when we banned it. And when we found strontium, a radioactive isotope in baby teeth, again, that's when we became more active in nuclear issues. Mothers can cross a lot of cultural and political divides. Everyone cares about breast cancer. Everyone cares about child health. These issues can be really unifying and powerful sources of change. I would encourage women to get informed and active. In fact, I think nothing is going to happen unless they do.
Florence Williams is a contributing editor at Outside Magazine and a freelance writer for New York Times, New York Times Magazine, Slate, Mother Jones, High Country News, O-Oprah, W., Bicycling and numerous other publications. Recently she was a visiting scholar at the University of Colorado's Journalism School. Her work often focuses on the environment, health and science. Her first book, BREASTS: A Natural and Unnatural History, was recently published by W.W. Norton. The manuscript was named a finalist for the 2011 Columbia/Nieman Lukas Work-in-Progress Award. She serves on the board of her favorite non-profit, High Country News, and lives with her family in Washington, D.C.
This post originally appeared on Moms Clean Air Force.