by Deborah Kotz
Excerpt: Only 5 to 10 percent of breast cancers arise from mutant genes that women inherit from their mother or father; the other 90 to 95 percent of these cancers are thought to stem from a panoply of causes like radiation treatments, obesity, excess alcohol consumption, prenatal exposure to DES, and hormone therapy — as well as exposure to dozens of chemicals.
Altering certain lifestyle habits by, say, losing weight or curtailing the use of hormones after menopause can certainly help reduce breast cancer risk. But what can women realistically do to avoid hundreds of chemicals that could potentially trigger breast tumors to grow and flourish?
Researchers from the Silent Spring Research Institute in Newton identified the most important chemicals that women should make an effort to avoid in order to lower their odds of getting breast cancer. At high exposures, these have been found to cause breast tumors in rats, and while they need to be better studied in people, early evidence suggests that they could cause harmful changes in breast tissue, according to the paper published in the journal Environmental Health Perspectives.
As of now, researchers don’t know how much these chemicals contribute to breast cancer risk compared to better known risk factors like excess body weight, early menstruation, and hormone therapy. That will take future studies to determine, said study leader Ruthann Rudel, who is research director at the Silent Spring Institute, a scientific research organization focusing on breast cancer prevention.