A new study adds to the growing evidence that chemical exposure increases the chance of getting cancer.

The study, published today by Environmental Health, concludes women who have worked in jobs with potentially high exposures to carcinogens and endocrine disruptors have elevated breast cancer risk. The industries that presented the most risk were automobile plastics manufacturing, bars/gambling, food canning, agriculture and metal working. Premenopausal breast cancer was highest in women who worked in automobile plastics and food canning, the study says. More than 2,000 women were studied, about half of whom had breast cancer.

U.S., Canadian and U.K. researchers conducted the six-year study of women in Essex and Kent counties in Canada's Southern Ontario. According to the Web site Public Integrity, women who worked at 40 plastics factories were included in the study. Many of them have been complaining for decades about terrible working conditions that caused nosebleeds, headaches, nausea and dizziness.

At bars and gambling establishments like casinos and racetracks, the study said, second-hand smoke may have contributed to the higher incidence of breast cancer. Working at night, which disrupts circadian rhythms and decreases melatonin production, might also be related, it said.

Exposure to Bisphenol A, nicknamed BPA, may have been one reason women who worked at food canning plants had higher rates of breast cancer, the study said. Many groups have targeted BPA as a potential carcinogen and have been fighting for its removal from packaging. But the study implied canning workers were more at risk of cancer than consumers. Food canning workers were exposed to BPA primarily from inhaling it when can liners were heated during production, while consumers generally are exposed when they eat food from epoxy-lined cans. "The bioavailabilty of BPA that has been inhaled or absorbed dermally has been found to be eliminated at a slower rate than BPA ingested through food or drink," the study said.

Regardless of how much and what kind of exposure, there is little doubt that toxic chemicals can hurt our health. Being informed about the potential risks can help financial advisors personally but also professionally, since companies that manufacture or sell products with suspect chemicals but ignore the risks are not good investments, especially for the long run.