Study Identifies 485 Chemicals in US Pesticides Linked to Breast Cancer

New research has identified at least 485 chemicals used in US pesticide products that are linked to breast cancer, raising questions about the safety of food and other products as early onset breast cancer rates increase globally. The peer-reviewed paper, published in Environmental Health Perspectives, highlights deficiencies in the regulation of US pesticides. It includes active pesticide ingredients and hundreds of so-called 'inert' ingredients that typically do not undergo thorough safety reviews. The Environmental Protection Agency (EPA) evaluates each pesticide ingredient's individual health risks but does not consider the entire pesticide formula or the exposure to multiple pesticides. These chemicals are found not only in agricultural pesticides but also in lice treatments, home lawn fertilizers, and flea and tick treatments. Jenny Kay, a co-author of the report from the Silent Spring Institute, stated, 'Adding these exposures up gets pretty consequential and concerning.' Breast cancer is the most commonly diagnosed cancer in the US, with incidence rates increasing by 1% per year, and slightly faster in women under 50. Pesticide use has also increased, with 84 of the identified breast cancer-linked chemicals present in the general population, although this number is likely an undercount. The review is part of a broader effort by the Silent Spring Institute to identify exposure to breast cancer-linked chemicals across various sectors. Approximately 500 such chemicals have been identified 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 inert status to avoid health scrutiny. Inert ingredients, often added as surfactants, are not biologically inert and can pose health risks. Kay noted that the EPA rejected a legal petition in 2023 to more stringently review inert ingredients. She also raised concerns about hormone-disrupting chemicals that can cause disease at lower exposure levels. The leadership of the EPA's pesticide and chemical safety offices includes former industry lobbyists, raising concerns about industry influence on regulatory practices. The Silent Spring Institute has called for an expansion of California's Proposition 65, which requires warnings for chemicals known to cause cancer or reproductive harm. The study identified 16 pesticides not listed under Prop 65, and the authors suggest that adding these chemicals could deter their use. Consumers can protect themselves by purchasing organic produce or products not treated with pesticides, and resources like Consumer Reports provide guidance on fruits and vegetables with high pesticide residues. A recent report indicated that about 25% of the nation's water intake and approximately 675,000 wells are contaminated with atrazine, a hormone-disrupting chemical linked to breast cancer. Water-filtration systems can help filter pesticides from water, with activated carbon and reverse osmosis being the most effective methods.