The Everyday Chemical That Makes Breast Cancer 5 Times More Likely in High Doses
Windsor, Ontario—For more than three decades, workers, most of them women, have complained of dreadful conditions in many of this city's plastic automotive parts factories: Pungent fumes and dust that caused nosebleeds, headaches, nausea and dizziness. Blobs of smelly, smoldering plastic dumped directly onto the floor. "It was like hell," says one woman who still works in the industry.
The women fretted, usually in private, about what seemed to be an excess of cancer and other diseases in the factories across the river from Detroit. "People were getting sick, but you never really thought about the plastic itself," said Gina DeSantis, who has worked at a plant near Windsor for 25 years.
Now, workers like DeSantis are the focal point of a new study that appears to strengthen the tie between breast cancer and toxic exposures.
The six -year study, conducted by a team of researchers from Canada, the United States and the United Kingdom, examined the occupational histories of 1,006 women from Ontario's Essex and Kent counties who had the disease and 1,146 who didn't. Adjustments were made for smoking, weight, alcohol use and other lifestyle and reproductive factors.
The results, published online today in the journal Environmental Health, are striking: Women employed in the automotive plastics industry were almost five times as likely to develop breast cancer, prior to menopause, as women in the control group.
These workers may handle an array of carcinogenic and endocrine-disrupting chemicals. They include the hardening agent bisphenol A (BPA)—whose presence in polycarbonate water bottles and other products has unnerved some consumers—plus solvents, heavy metals and flame retardants.
Sandy Knight, who worked at two Windsor plastics plants from 1978 to 1998, had a breast cancer scare in 2000, when she was 41. The cancer was at Stage III—"invasive and fast-growing," said Knight, 53, who now works at a Ford parts distribution center near Toronto. She had a single mastectomy and, following 10 years of hormonal treatment, is in remission.
Asked if she believed her disease was work-related, Knight said, "I'm suspicious of it because of all the exposures we had." She remembers the "nauseating kind of odor," the burning eyes and headaches, all the women with cancer, sterility and miscarriages. She's upset that little seems to have changed at some plants.
"Why am I speaking to people today, in 2012, who are doing the same processes I did in 1980?" Knight asked. "It just seems like we're fighting the same battle. A lot of these chemicals should be removed from the workplace ."
The study population included women who had worked at more than 40 plastics factories in the Windsor area. But the implications are broader: Workers in similar plants around the world are exposed to many of the same chemicals. So are members of the public, who encounter the substances—albeit in lower doses—in the course of their daily lives.
"These workplace chemicals are now present in our air, water, food and consumer products," said one of the two principal investigators, James Brophy, an adjunct faculty member at the University of Windsor and a former occupational health clinic director. "If we fail to take heed then we are doing so at our own peril."
Jeanne Rizzo, president of the Breast Cancer Fund , a San Francisco-based group that has pressed for more research into environmental causes of a disease that claimed nearly 40,000 lives in the United States last year, called the Windsor study "a very powerful piece of work. The piece that's really been missing for female breast cancer is occupation."