New research has identified at least 485 chemicals used in U.S. pesticide products that are linked to breast cancer, raising concerns about the safety of food and other products. This comes as early onset breast cancer rates are increasing worldwide. The study, published in Environmental Health Perspectives, a top journal from the American Chemical Society, highlights issues with how U.S. pesticides are regulated. Public health advocates argue that current regulations have significant gaps, especially regarding so-called "inert" ingredients—substances that are not typically reviewed for safety. These inert ingredients are often added to help the active pesticide ingredients work more effectively, but they are not subject to the same rigorous safety assessments. The Environmental Protection Agency (EPA) only evaluates the health risks of each pesticide ingredient individually, rather than considering the entire pesticide formula or the combined effects of exposure to multiple pesticides. These chemicals are not only found in agricultural pesticides but also in lice treatments for children, lawn fertilizers, and flea and tick treatments. "Adding these exposures up gets pretty consequential and concerning," said Jenny Kay, a co-author of the study with the Silent Spring Institute, a non-profit organization focused on environmental health. "We wanted to bring more attention to the pesticides in different products." Breast cancer is the most commonly diagnosed cancer in the U.S., and its incidence rates have increased by about 1% annually, with a slightly faster rise among women under 50. Federal health data shows that 84 of the chemicals linked to breast cancer are present in the general population. However, scientists believe this number is an undercount, as it does not track many of the compounds identified by the Silent Spring Institute. The review is part of a larger effort to identify where people are exposed to breast cancer-linked chemicals in everyday life. The study found about 500 such chemicals in common consumer goods and 462 in drinking water. Only about 145 of the pesticide chemicals identified were registered with the EPA as active ingredients, suggesting that the chemical industry may be using the "inert" classification to avoid health scrutiny or exploit regulatory loopholes. Inert ingredients, which include substances like Pfas "forever chemicals," are often added to enhance the effectiveness of pesticides. "They are not biologically inert, they are just called inert because they do not target the pest," Kay explained. The EPA has resisted calls for more stringent reviews of inert ingredients, and some hormone-disrupting chemicals are dismissed due to a "non-monotonic dose response," where lower exposure levels can cause disease rather than higher ones. The study also points to concerns about the influence of the chemical industry on the EPA. Top officials in the agency's pesticide and chemical safety offices have included former industry lobbyists, raising questions about impartiality. The Silent Spring Institute has called for expanding California's Proposition 65, which requires warnings for cancer-causing or reproductive-harming chemicals. People can reduce their exposure by choosing organic produce or products free from pesticides. If that is not possible, resources like Consumer Reports offer guidance on which fruits and vegetables typically have the highest pesticide residues. Water filtration systems can also help remove pesticides from drinking water, with activated carbon and reverse osmosis being the most effective methods.