Reviewing hundreds of existing studies and databases, the team produced what it called "the most comprehensive compilation to date of chemicals identified as mammary carcinogens." No new chemical testing was conducted for the reports.
The researchers named 216 chemicals that induce breast tumors in animals. Of those, people are highly exposed to 97, including industrial solvents, pesticides, dyes, gasoline and diesel exhaust compounds, cosmetics ingredients, hormones, pharmaceuticals, radiation, and a chemical in chlorinated drinking water.
"Almost all of the chemicals were mutagenic, and most caused tumors in multiple organs and species; these characteristics are generally thought to indicate likely carcinogenicity in humans, even at lower exposure levels," they reported.
For many of the compounds, the federal government has not used animal breast cancer data when conducting human risk assessments, which are the first step toward regulating chemicals or in setting occupational standards to protect workers. Companies are not required to screen women who work with the chemicals for breast cancer.