Devra Davis

In your first book, When Smoke Ran Like Water, which won a National Book Award bronze metal, you describe how the illnesses suffered by your family and neighbors in a town plagued by steel-industry pollution motivated your drive to investigate the environmental causes of disease. When and why did you begin to look at the unhealthy impact of chemicals in daily products we use?

I've been concerned about chemicals all my life, because of those early exposures. But it was in the 1970s that I became aware of patterns of cancer in populations exposed to chemicals and radiation. Meanwhile, there was this attitude on the part of our government that supported research into detection and treatment, but not prevention. Yet about two-thirds of cancers have an environmental cause, and only one out of 10 women with breast cancer have a genetic history of the disease.

You're the founder and director of the Center for Environmental Oncology at the University of Pittsburgh Cancer Institute. Does the Center treat patients, do research, or both?

We do both. And to avoid exposing patients to toxins, we've used least-toxic, green products in building, decorating and cleaning the Center.

Unlike most hospital centers, you also give advice on lifestyle choices that may help with prevention and recurrence. Why is that?

From the beginning, a large part of our mission has been to educate patients and their families about how they can avoid exposures to chemicals that are known or suspected to cause cancer, disrupt hormonal systems and cause nervous system harm. Our government's policy is that chemicals are innocent until proven guilty, so they aren't regulating chemicals that have been linked to these diseases. When chemicals are tested for health effects, they're examined individually—whereas in reality, we're exposed to combinations of multiple chemicals in products and polluted air every day. That's why the Center is taking a precautionary approach, rather than waiting for the last word on environmental exposures and cancer, which is a disease that can take decades to develop.

These include a lot of products aimed at women. According to the Breast Cancer Fund, one-third of personal care products contain at least one chemical linked to cancer. What are some of the chemicals we should be most concerned with avoiding, say, in household products and cosmetics?

We also know that it's the accumulation of all these toxic ingredients, not the use of one product alone, that is the problem. Read labels, and choose products that do not list parabens (methyl-, butyl- or propyl-), preservatives that have caused proliferation of breast cancer in the lab, yet are used in many deodorants, moisturizers, makeups and shampoos. You won't see phthalates on labels, but to avoid them, reject products listing "Fragrance"—this connotes synthetic fragrance and, likely, phthalates; look instead for a listing of specific plant essential oils. To keep your indoor air as free as possible of toxic petrochemicals known as volatile organic compounds (VOCs), don't use synthetic pesticides, and do choose paints, stains and finishes labeled "low-VOC" or, best of all, "no-VOC." To hold water or food, choose lightweight stainless-steel or least-toxic plastics. Avoid containers, including many Nalgene bottles, which are made of polycarbonate (#7) plastic, which can leach hormone-disrupting bisphenol-A (BPA). All these substances basically behave like hormones in the body, and we know that the more hormones you're exposed to in your life, the higher your risk of breast cancer. A good place to look to see what's in your specific personal care products is Nottoopretty.org. For safest food and water containers, including greenest plastics, see GreenerPenny.com.

Early menarche (the onset of menstruation) and late menopause are considered breast-cancer risk factors because they expose a woman to estrogen for a longer portion of her life. Recent studies, including a new analysis by Sandra Steingraber for the Breast Cancer Fund, are showing that puberty is occurring earlier in American girls and thus raising their breast cancer risk. You've done similar research, haven't you?

Yes. As Steingraber noted, one culprit in early puberty is hormonal hair products marketed to African American girls. Our Center participated in a study on breast growth in baby girls, and the link to personal care products. We've also identified 216 chemicals associated with the growth of mammary tumors, in the Cancer Supplement of June 15, 2007. You can read these studies and others on our website, environmentaloncology.org.

Do you wear makeup every day? How do you choose it?

No, I don't wear makeup every day, but when I go climbing I do wear sunscreen, which is a challenge! It's hard to find one that's free of suspect chemicals, but I think that the mineral titanium dioxide as a sunblock in a cream is really okay. When I use a powder or foundation it's one of the mineral makeups. For lotions I choose products with as many natural ingredients as possible, such as Avalon or Aveda, and I make my own skincare treatments when I can.

What's your eco-sin—are there some products you can't resist even though you know they're not pure?

Sure. Mascara, for instance.

Your new book is called Secret History of the War on Cancer—what's the secret?

The war on cancer has been the wrong war against the wrong enemies with the wrong weapons, because it has been attacking the disease but not the things that cause it. In the 1930s, the U.S. government announced that benzene, a chemical in gasoline, was known to cause cancer. Scientists back then also knew that tobacco, diagnostic and solar radiation, and hormones could cause cancer. But this information wasn't acted on. Part of the reason was the advent of World War II, which focused us on immediate survival, whereas cancer is a long-run disease. And because some of the cancer research had been done in Nazi Germany, it was suppressed. But President Nixon launched the War on Cancer in 1971 without declaring war on cigarettes, even though the Surgeon General had announced in 1964 that smoking caused lung and larynx cancer. Asbestos still hasn't been banned in the U.S., and although it was also known in 1971 that some synthetic hormones cause cancer, at least 62,000 of the 80,000 industrial chemicals on the marketplace have still not been tested for carcinogenicity.

All this seems to have served the chemical industry well. You report in your book that Novartis, ICI and other companies make billions both from the production of chemicals that cause cancer and the drugs used to treat it. What new research is the Center launching to identify cancer causes?

We're trying to find out why more young people are getting colorectal cancer in Egypt. We think the reason is pesticides. We're setting up a foundation with proceeds from the book to fund this and other cancer research.

If you could change one thing about our societal approach to fighting breast cancer, what would it be?

Blaming people for their disease, making women feel it's their fault.