Women employed in sectors such as automotive plastics and food canning — where there are potentially high exposures to carcinogens and endocrine disruptors — have an elevated risk for developing breast cancer, according to a study published in the academic journal Environmental Health.
“This really demonstrates that occupational exposure is a very important influence on the rates of this disease,” said Jim Brophy, an adjunct professor at the University of Windsor and co-author of the paper.
Between 2002 and 2008, the study’s authors — who included Eleanor Maticka-Tyndale, a sociology professor at the University of Windsor — recruited 1,005 women who had been diagnosed with breast cancer, collecting data on their occupational and reproductive histories, and compared them with 1,147 control subjects.
The study found specific sectors with elevated risk included agriculture, bars and gambling, automotive plastics manufacturing, food canning and metalworking. The highest risk sector for premenopausal breast cancer was in the automotive plastics sector, found the study Breast Cancer Risk in Relation to Occupations With Exposure to Carcinogens and Endocrine Disruptors: A Canadian Case-Control Study.
Participants were asked to fill out a questionnaire that captured data on reproductive risk factors such as menstrual and menopausal history, use of hormone replacement therapy and oral contraceptives, and family history. They were also asked about demographic and lifestyle risk factors, including income, education, physical activity, weight and body mass index, alcohol use, smoking history and residential history. Employment history included start and end dates for up to 12 jobs, as well as descriptions of job activities that were used to categorize occupation, industry and exposure.
The findings are significant because research regarding occupational exposures and breast cancer risk has generally been a neglected topic, said Brophy, adding there are only three previously published studies of occupation and breast cancer similar to this one that include detailed work and reproductive histories.
“Work-history-based occupational breast cancer studies often lack demographic and reproductive status information,” said the paper. “Studies with adequate demographic and reproductive status information often lack detailed work history data beyond current employment.”