Researchers have been trying to understand what factors increase a woman’s chance of developing breast cancer. A Canadian study suggests there may be occupational contributors to the disease.
The new investigation suggests women with occupational exposure to certain plastics and other environmental chemicals that disrupt hormones could contribute to risk of breast cancer in findings published in the journal Environmental Health.
Last year, the Institute of Medicine (IOM) published findings that there was no clear link between environmental factors and breast cancer risk. The study, supported by the. Komen for the Cure cost a whopping $1 million.
Instead of environmental chemicals, the Komen funded study concluded hormone therapy, excess weight gain after menopause and ionizing radiation are factors most likely to raise risk of cancer of the breast.
The new results suggest women who work with automotive plastics, in the food canning industry; metal working, bars and agriculture appear to be at highest risk of developing breast cancer.
The conclusions come from data collected in a study from Southern Ontario, Canada.
Dr. James T. Brophy PhD and colleagues at the Occupational and Environmental Health Research Group (OEHRG) at Stirling University in the U.K who analyzed the data found a 42 percent increase in the disease among women working 10 years or more in occupations that expose them to chemicals like polyvinyl chloride, or PVC, plastic; acrylonitrile; formaldehyde and styrene.
Women who work in agriculture are exposed to pesticides. In bars, tobacco smoke could contribute to risk of the disease.
Brophy told BBC news, “…Studies have shown that breast cancer incidence rose throughout the developed world during in the second half of the 20th Century as women entered industrial workplaces and many new and untested chemicals were being introduced.
Our results highlight the importance of occupational studies in identifying and quantifying environmental risk factors and illustrate the value of taking detailed occupational histories of cancer patients.”
A spokeswoman for the U.S. Occupational Safety and Health Administration, said, “We look forward to reading this paper … and plan to explore how we may use the findings in protecting workers from hazardous exposures.”
Brophy said the study contributes to a ‘neglected’ area of research. One of the problems with the investigation is that it fails to show cause and merely suggests a link between environmental chemicals and breast cancer. Brophy and his team were unable to track were the women worked and exactly how much chemical exposure they had in the workplace because most of the industries are closed.
For the study, Brophy and his team interviewed women about their occupational history. They compared 1,006 women diagnosed with breast cancer to 1,147 age-matched women without the disease in southwestern Ontario.
The potential good news for women is that the finding should lead to a deeper look into breast cancer causes that could come from harmful chemicals.
"The identification of several important associations in this mixed industrial and agricultural population highlights the importance of occupational studies in identifying and quantifying environmental risk factors and illustrates the value of taking detailed occupational histories of cancer patients, “ Brophy said in a press release.
Singer Sheryl Crow who was diagnosed with breast cancer in 2006 has been an advocate of studies to understand how the environment affects a woman’s risk for breast cancer. In an 'Eye to Eye’ interview, Crow advocated for funding for more research.
Investigators for the current study suggest women in occupations that include farming and jobs that expose them to plastics that disrupt the endocrine system, shown in animal studies, could possibly contribute to breast cancer.
As a note of caution, the American Chemistry Society warns that the study is worthy and important, but it may be "inappropriate" as a basis for research and only shows a 'statistical association' between breast cancer and occupational exposure to chemicals.