Introduction

A new summary of the science makes a strong case for occupational links to breast cancer and calls on Congress, regulators and researchers to pay more attention to chemical exposures and other risk factors.

“Working Women and Breast Cancer: The State of the Evidence,” is the product of more than two years of work overseen by the San Francisco-based Breast Cancer Fund. A panel of experts reviewed scientific studies, most published in the past 25 years, and found ties between the disease and exposures to solvents; pesticides; tobacco smoke; ionizing radiation and other toxic materials. There also was an association with night shift work.

“Research is inadequate, but there is enough to raise alarm about women’s work, occupational exposures and breast cancer,” the report concludes. “At the same time, policies are insufficient to protect worker health.”

The report touches on a subject raised by the Center for Public Integrity’s “Unequal Risk” project, launched in June. The series noted that enforceable workplace exposure limits for many toxic substances don’t exist, and those that have been set by the Department of Labor’s Occupational Safety and Health Administration in most cases aren’t protective. As the Breast Cancer Fund put it, “women and men in the workplace are routinely exposed to levels of chemicals that would not be allowed in their homes. The relatively lax requirements of some occupational settings lead to both higher levels and longer exposure periods than would otherwise occur in a residential or commercial setting.”

Among the report’s recommendations:

Women should be included in occupational studies. They have “historically been excluded…which means that health issues that predominantly affect women, including breast cancer, have been at best understudied and at worst ignored.”

Congress should pass legislation “to change the paradigm on how chemicals in the workplace are managed,” empowering OSHA to make employers use safer alternatives when possible or to “incentivize innovation” when not.

OSHA “should take full advantage of its current authority” by setting stricter exposure limits. The agency tends to allow exposures that can cause one additional case of cancer for every 1,000 workers; the Environmental Protection Agency, in contrast, seeks to hold cancer risks to 1 in 100,000 or 1 in 1 million when it regulates exposures to the general public.

In 2012, the Center published a story about high rates of breast cancer among female workers in Canada’s automotive plastics industry. The story reported the results of a six-year study that found the women were almost five times as likely to develop the disease, prior to menopause, as women in a control group.

The workers had been exposed to a variety of solvents, heavy metals, flame retardants and the hardening agent bisphenol A, used in polycarbonate water bottles and other products. “A lot of these chemicals should be removed from the workplace,” breast cancer survivor Sandy Knight, who worked at two Ontario plastics plants from 1978 to 1998, told the Center.