Breast Cancer and Your Environment

There may be no two scarier words for women than breast cancer.

The most common invasive malignancy among women around the world, breast cancer’s rates during the last several decades have nearly tripled in the United States. Today, this cancer is the leading cause of death in U.S. women in the prime of their lives—between their late 30s and early 50s.

No other epidemic has seemed so elusive—and so immune to preventive measures. When it comes to heart disease, we can lower cholesterol and improve fitness regimens to alleviate or even elude it. To avoid lung cancer, we can stop smoking or never smoke. To avoid AIDS, practice safe sex.

So what prospects are there for stopping this cancer that has spread across the American landscape like an invisible, invincible scourge?

“With breast cancer, there’s no magic bullet, no straight line like that from cigarettes to lung cancer, but we are honing in on clues to mechanisms behind this complex disease—and ways to possibly decrease our risks,” says Dr. Cheryl Perkins, senior clinical advisor for scientific developments for Susan G. Komen for the Cure, the Dallas-based cancer-fighting organization.

At the invitation of Komen, a multi-disciplinary team led by researchers from the Silent Spring Institute, with Harvard Medical School, Roswell Park Cancer Institute and the University of Southern California identified 216 chemicals pervasive in our environment that cause breast tumors in animals.

The study is groundbreaking, some experts say, because it begins to identify potentially preventable exposures to a wide range of environmental chemicals, behaviors, and lifestyles that may be promoting this disease. Most of the conventional risk factors for the disease, such as age, gender, family history, and age at first full term of pregnancy “can’t be modified,” according to Komen.

“We’ve spent far too long detecting and treating the disease,” argues Devra Lee Davis, an Professor of Epidemiology at the University of Pittsburgh's Graduate School of Public Health and director of the Center for Environmental Oncology at the university's Cancer Institute, “which means that we’ve become efficient at processing more and more sick people without identifying promising avenues of prevention.”

Like other cancers, breast cancer

Because breast cancer rates can vary so drastically from place to place, researchers have long assumed that there are contributing environmental factors. The fact that there’s a fivefold greater risk of getting it by living in an industrialized country is one clue, say the Silent Spring Institute researchers. A 1989 study by the U.S. Environmental Protection Agency found that breast cancer rates were higher in the 339 U.S. counties with hazardous waste sites and groundwater contamination than in other areas. However, relatively few epidemiological studies—looking at the illness across various populations—have been conducted, according to these researchers.