Breast Cancer Risk and the Dirty Air We Breathe

Last week, the American Lung Association came out with its annual State of the Air report, and concluded that six out of every ten Americans live in communities with unhealthy air. I read these results not only as the head of environmental organization, but also as a breast cancer survivor.

What does breast cancer have to do with air pollution? Most of us are familiar with the connection between smog-covered skies and asthma attacks. (See my colleague David Pettit's recent post about what Southern California's pollution does to its residents.)

But there are also over 200 chemicals in air pollution--called polycyclic aromatic hydrocarbons (PAHs)--that may also lead to cancer, including cancer of the breast. PAHs are the chief component of soot, and enter the air via burning of coal, oil, diesel, gasoline, wood, garbage, tobacco, and even charbroiled meat.

I also read the study's results as a mother. My three daughters--who already have an elevated risk of breast cancer because of my diagnosis--have recently lived in the heavily polluted cities of Johannesburg, Amman, and New York. The United States has taken some steps to reduce air pollution--it still needs to do much more--but tens of millions of women and girls around the globe are exposed to alarmingly high levels of carcinogenic pollutants.

What Air Pollution Can Do to Breast TissueScientists are just beginning to understand the connections between PAHs and breast cancer, but here is what they have discovered so far.

PAHs cause mammary tumors in rats. PAHs appear to increase breast cancer risk in a variety of ways. Common PAHs mimic estrogen, and elevated levels of the hormone are known to contribute to tumor growth.

But there is another, more insidious way that PAHs threaten our health. Once in the body, PAHs can bind to genetic material (DNA) and form something with the ungainly name of PAH-DNA adducts. These adducts jumpstart a series of cell changes that can short circuit cell signals, interfere with DNA repair within cells, and ultimately lead to DNA mutations.

I know from my experience being tested for the so-called breast cancer genes that genetic mutations can lead your cells down paths you don't want them to go.

Several studies have connected high levels of PAH-DNA adducts and breast cancer. One study, from the Long Island Breast Cancer Study Project, discovered that women with the highest levels of PAH-DAN adducts had a 50 percent increased risk of breast cancer. Another compared breast tissue from women who had breast cancer with women who had benign breast diseases and found that the cancerous samples were two times as likely to have PAH-DNA adducts.

PAHs, Cigarette Smoke, and Breast Cancer RiskPAHs don't just come from diesel trucks and industrial smoke stacks. They also come from cigarette butts. PAHs in tobacco smoke have been linked to breast cancer, but there is a window when women are particularly vulnerable: the teen years.

If a girl is exposed to secondhand smoke during the time when her breasts are developing through puberty, she is more at risk for getting breast cancer later than a woman who breathes in secondhand smoke after she gives birth to her first child.

A study sponsored by the California Air Resources Board found that women exposed to secondhand smoke have up to 90 percent greater risk of developing breast cancer. And in 2006, the California EPA concluded: "overall, the weight of evidence...is consistent with a causal association between [environmental tobacco smoke] exposure and breast cancer in younger, primarily pre-menopausal women."

Now We Need PreventionThere is a lot more we need to learn about the way PAHs interfere with human cell function, but we know enough to start protecting ourselves from this hazard.

Here are NRDC's recommendations for reducing breast cancer risk for women and their daughters:

• Pass tougher standards for diesel-burning vehicles, a leading source of PAHs. Thanks in part to NRDC, pollution from diesel trucks and even off-road vehicles has declined, but diesel fleets could still become cleaner.

• Enforce the Clean Air Act provisions that protect the public against cancer risks greater than 1 in 1 million caused by toxic air pollution from industrial polluters. The Bush administration refused to achieve this level of protection and instead adopted policies accepting cancer risks as high as 250 in 1-million and even 400 in 1 million. The Obama administration can and should do better.

• Forbid the use of federal funds in connection with any project--such as an expansion of diesel-heavy shipping terminal--that can be shown to increase cancer risk by more than 1 in a million.

• Require that all existing coal-fired power plants adopt modern pollution controls.

• Ban the incineration of industrial waste.

• Extend nonsmoking bans in the workplace and public spaces to reduce the risks from secondhand smoke.

Here are a few ways you can protect yourself from PAH exposure:

• Stop smoking, urge those you love to stop smoking, and limit your time in the presence of smokers.

• Avoid spending significant time in the freeway traffic, where in-vehicle exposure can run high.

• Avoid living, working, or attending school directly adjacent to freeways, where pollution levels spike (for instance, within 500 feet).

This post originally appeared on NRDC's Switchboard blog.

Comments

[SonofLiberty1]

And Air Pollution is not the only thing that can cause Breast Cancer either...

Light Pollution can.

As in any "extra light" streaming in through your bedroom window or even from
anything left on while you sleep in your bedroom will do it.

http://www.oprah.com/article/omagazine/200808_omag_cancer_risk

[SonofLiberty1]

Rhett,

The evidence is overwhelming that dirty air does cause people to get sick.
And not just folks who have asthma either.

Either way, what do you suggest?

That people with a genetic disposition to anything be cast aside?

In any event, we knew about air pollution before the hazards of cigarette smoke because cigarrette
companies kept all the data to themselves and there is no doubt about that.

Maybe you should take it up with an MD instead of being a mouthpiece for conservative viewpoints?

Dirty air isn't healthy period no matter if it comes from smoking something or just breathing in smog.

[Rhetticent]

99, I would challenge your assertion that 30% of the cancers we experience are caused by environmental pollutants. I'm sure you can find a study that says that, but it would be interesting if they'd done the same study and analyzed how many people with cancer read the bible. If there was a close relationship, would that mean that reading the bible causes cancer?

Those of you younger than baby boomers have no idea of the amounts of second-hand smoke we experienced in the 50's and 60's. Smoking by both parents was common, in the home, cars, airplances, church, courtrooms EVERYWHERE. 75% of americans were smokers. If second hand smoke caused the problems we hear about today, there would have been epidemics of them when I was young.

Evidence is overwhelming that heredity is the single most important factor relating to cancer. Maybe we should just accept that, and not make everyone so paranoid about everything around them. One thing I know is that I'm going to die. Of the deaths I've seen in my family, cancer is not a bad way to go, and sure beats living to 100 when your brain only lives to 90. And remember, the corporations you talk about also provide the products that are used to treat sick people: not all of them are worthless, polluting enterprises.

[nintynine]

Dr. Samuel Epstein is my source and has been before a sleepy minded Congress on many occasions that started with President Nixon launching the 1971 war on cancer. Since then cancer incidence rates (adjusted for the aging population) have escalated to epidemic proportions. This award-winning author and doctor, whose 1978 book The Politics of Cancer shook the political establishment by showing how the federal government had been corrupted by industrial polluters, has written a book that is sure to be of equal consequence. Cancer-Gate: How to Win The Losing Cancer War, we're losing the winnable war against cancer, while virtually ignoring strategies for preventing cancer in the first place.

Epstein also argues that consumers have the basic right-to- know, through explicit labeling, of known carcinogens in consumer products, food, cosmetics and personal care products, and household products. Cancer-Gate also calls on state and local governments to utilize public databases to inform about local carcinogenic hazards posed by chemical industries in their communities. State and local governments should also be required to develop ordinances to obtain such information, and should develop remedial initiatives to prevent hazardous exposures to industrial carcinogens.

About the author: Dr. Epstein is Professor Emeritus of Environmental and Occupational Medicine at the School of Public Health, University of Illinois at Chicago, and Chairman of the Cancer Prevention Coalition. He is an internationally recognized authority on the causes and prevention of cancer, and has published some 270 scientific articles and 11 books.

[quidam56]

Appalachia is a toxic moonscape because of greed. Our lakes, rivers and watersheds are tainted with Acid Mine Drainage ( AMD ) and heavy metals visable to the eye, but of course everything is at a safe and acceptable level, alledgedly our raw water is also poisoned with e-coli at 18 times the safe and acceptable level. Our health care system is dumping Methicillin Resistant Staphylococcus Aurea's ( MRSA ) into our communities, but I am sure that is at a safe and acceptable level too. When willl we wake up ?

http://www.wisecountyissues.com

[nintynine]

Environmental pollutants are responsible for 30% of the cancers we’re experiencing. All the items that Francis recommends are necessary requirements that should be implemented to protect our health. Another aspect we need to focus on is nutritional eating for prevention, building our immune system, sound sleep that enables our bodies to repair and rejuvenate and lower stress levels. The article, Kick Cancer in the Can, Food For Thought is about a women, diagnosed with stage IV breast cancer that was given 6 months to live and kicked it out in 7 months. Our health is not a game and corporations need to be responsible for the pollutants that are released into our air, water and soil.