October is Breast Cancer Awareness Month. The international health campaign aims to promote screening and reduce the risk of the disease, which affects approximately 2.4 million women worldwide. One way to reduce the risk of breast cancer is to identify exposure sources of known or potential breast carcinogens as a first step towards reducing exposure.
Last October, in 2025, the Food Packaging Forum (FPF) reported that 230 potential breast carcinogens are food contact chemicals (FCCs), meaning that they are present in food contact materials or articles and/or can migrate from them into food (FPF reported and here). FPF’s analysis used the Silent Spring Institute’s list of potential breast carcinogens, which includes a total of 921 chemicals (FPF reported).
On September 23, 2026, the Silent Spring Institute, together with scientists from the University of California, Berkley, United States, published an article in the journal Environmental Health Perspectives identifying further exposure sources and risk-reduction strategies and informing research on breast-cancer-relevant chemicals.
The authors reported production volumes for 143 breast cancer-relevant chemicals, with available data indicating production volumes of at least 1 million pounds in 2019. They further reported that billions of pounds of breast carcinogens were emitted into the air in 2020 and tens of millions of pounds were released into the environment through industrial activities in 2024.
When analyzing their presence in products, the researchers identified 500 breast carcinogens as likely to be present in consumer products, including food contact articles. Among these 500 chemicals, 191 were endocrine-disrupting chemicals (EDCs), of which 88 were also genotoxic. In addition, 462 breast carcinogens were found in food, 162 in drinking water, 485 in pesticide formulations, 142 in pharmaceuticals, and 106 in construction materials.
Eighty-four of the breast carcinogens have been detected in the NHANES biomonitoring study, demonstrating their presence in humans. Based on predictions from the SEEM3 consensus model, the scientists estimated median intake at 1 μg/kg/day or more for 7 breast carcinogens, between 1 and 1000 ng/kg/day for 425, and less than 1 ng/kg/day for 440 breast carcinogens.
The authors concluded that their findings “indicate substantial uptake of breast carcinogen chemicals by the population at large because of product use, ingestion, and exposure to chemicals released to environmental media. At the same time, the limited biomonitoring data highlights critical gaps that are a barrier to designing health studies that accurately capture relevant exposures, including mixtures.”
As a means of reducing exposure, lead author Jennifer E. Kay and colleagues recommend restricting the use of these chemicals in common products and regulating contaminants in drinking water. In addition, they prioritized 39 breast carcinogens for further research and policy interventions based on their production volume, hazard properties, and predicted general population exposure. These include, for instance, bisphenol A (CAS 80-05-7), di(2-etylhexyl) phthalate (CAS 117-81-7), 2-methylaniline (CAS 95-53-4), hydroquinone (CAS 123-31-9) and octadecanoic acid (CAS 57-11-4), all of which are included in FPF’s list of potential mammary carcinogens in food contact materials that were detected in migration experiments published in 2020, 2021, or 2022 (FPF reported).
For their study, Kay et al. collected information on breast carcinogens’ production volumes, uses, sources of exposure, releases into the environment, and human exposure levels from US government databases.
Reference
Kay, J. M. et al. (2026). “Guiding Risk Reduction for Breast Cancer-Relevant Chemicals (BC-Chems): Chemical Production Volumes, Sources, Intake Levels, Emissions, and Regulations.” Environmental Health Perspectives. DOI: 10.1021/EHP.6c00022
