Your Searchable Guide to Breast Cancer and the Environment
What does the science actually say about the link between the environment and breast cancer? For decades, that question has been difficult to answer — not because the evidence doesn’t exist, but because it has been scattered across thousands of journals, hidden behind paywalls, and written in language that requires a doctoral degree to decode. Today, that changes.
BCPP is proud to announce the launch of the State of the Evidence on Breast Cancer — a first-of-its-kind, publicly accessible, searchable database of peer-reviewed scientific literature linking environmental exposures to breast cancer risk. You can explore it now at bcpp.org/evidence.
This resource is the culmination of years of rigorous scientific work. It is built on a foundation that BCPP has been constructing since 2002, and represents our deepest, most comprehensive synthesis of the environmental breast cancer evidence base to date.
A Legacy of Translating Science into Action
BCPP’s relationship with this body of evidence is long and personal. In 2002, health science writer and breast cancer survivor Nancy Evans authored BCPP’s inaugural State of the Evidence report — a groundbreaking document that presented the then-radical argument that environmental exposures, not genetics alone, were driving breast cancer rates. [1] That report helped redirect the entire mission of this organization toward primary prevention and set the template for everything that followed.
Since 2002, BCPP has published multiple editions of State of the Evidence linking toxic chemicals and radiation with breast cancer incidence. The most recent peer-reviewed edition, published in the journal Environmental Health in 2017, examined hundreds of studies published in the eight years prior and concluded that exposures to a wide variety of toxicants found in common, everyday products can increase the risk of breast cancer. [2] That report was the 31st major scientific publication in BCPP’s history. [3]
The new database you see today is the living evolution of that work — no longer a static report published every several years, but a continuously updated, interactive resource that puts the science directly in your hands.
What Went Into Building This Database
The new State of the Evidence database is grounded in a systematic review methodology developed by BCPP scientists, covering peer-reviewed literature published from 2018 through 2025. The methodology was designed to be both rigorously scientific and practically useful for policymakers, advocates, and the public alike.
The research team conducted scoping literature searches using PubMed, combining “breast cancer etiology” with more than 100 specific environmental exposure terms across eight major categories:
- High-priority endocrine disrupting compounds — Phthalates, bisphenols, parabens, and PFAS (per- and polyfluoroalkyl substances), the so-called “forever chemicals” now found in everything from cookware to rainwater.
- Place-based chemicals — Organic solvents, volatile organic compounds (VOCs), pesticides, and polycyclic aromatic hydrocarbons (PAHs), which disproportionately affect communities near industrial sites and agricultural areas.
- Chemicals in products — Flame retardants, heavy metals, quaternary ammonium compounds, and sunscreen ingredients that enter the body through everyday consumer goods.
- Case studies with extensive evidence — DES (diethylstilbestrol), DDT, and hormone replacement therapy, which represent some of the most thoroughly documented environmental links to breast cancer in the scientific literature.
- Physical factors — Radiation, shift work, light-at-night, and noise exposure, reflecting how the built and occupational environment shapes cancer risk.
- Diet and lifestyle factors — Food, vitamin D, alcohol, tobacco, and physical activity, integrating modifiable behavioral factors alongside chemical exposures.
- Systemic social factors — Occupational exposures and health disparities, acknowledging that environmental breast cancer risk is not distributed equally across populations.
- Physiological factors — Infertility treatment, the microbiome, inflammation, age at menarche, and developmental exposures, capturing the biological windows during which environmental insults have the greatest impact.
The Numbers Behind the Database
The scope of this effort is remarkable. Initial literature searches yielded 5,041 articles. After removing 841 duplicates, the team screened 4,197 articles, excluding 2,448 studies that did not meet inclusion criteria — including studies focused solely on genetic determinants without environmental interactions, studies on genetic testing, and treatment-focused research. What remained were 1,749 peer-reviewed studies directly examining environmental and lifestyle risk factors for breast cancer, all rigorously screened, tagged, and organized for public use. The team used Zotero and Covidence software for reference management, duplicate removal, and systematic screening.
The most frequently represented topics in the database reflect both the breadth of environmental breast cancer science and the areas where evidence has grown most rapidly in recent years: diet, bisphenols, pesticides, hormones, chemicals in products, metals, phthalates, alcohol, and PFAS. When BCPP published its 2017 State of the Evidence, PFAS research was in its early stages. Today it is one of the most active frontiers in environmental health science, and the database reflects that urgency.
Why a Searchable Database — and Why Now
The creation of this database reflects something important about where breast cancer prevention science stands in 2025. Most women who develop breast cancer have no family history of the disease, suggesting an environmental link — a fact affirmed by the President’s Cancer Panel, the National Institute of Environmental Health Sciences, [4] and now by nearly 1,750 peer-reviewed studies gathered in one place. 90% of breast cancer cases are not linked to family history, but to lifestyle, environmental, and toxic chemical exposures. [5]
Yet for all this evidence, the public conversation about breast cancer still overwhelmingly focuses on genetics, early detection, and treatment. The environmental dimension — the exposures that happen before cancer develops, the ones that are actually preventable — remains underrepresented in health education, policy debates, and clinical guidance.
Part of the reason is access. Scientific literature is technically public, but practically inaccessible. A 2023 study in Scientific Reports found that in counties with poor environmental quality compared to those with good environmental quality, total breast cancer incidence was higher by 10.82 cases per 100,000 persons — the kind of finding that should reshape public health policy but rarely makes it to the people and communities most affected. [6] The State of the Evidence database is designed to close that gap.
The database is also a living infrastructure for BCPP’s ongoing science translation work. As new studies are published, they can be screened, tagged, and added — turning what was once a periodic report into a continuously updated surveillance system for emerging environmental breast cancer research.
What You Can Do With It
Whether you are a researcher looking for the latest studies, a parent trying to understand what chemicals in personal care products mean for your family, a clinician advising patients on modifiable risk factors, or a policy advocate building the evidence base for legislation, the State of the Evidence database was built for you.
Search by chemical. Search by exposure category. Filter by the type of study. Follow the evidence wherever it leads. And when you find something that matters — share it.
This database exists because BCPP believes that science belongs to everyone who stands to be harmed by it — which is all of us. The evidence linking our environment to breast cancer is substantial, growing, and now searchable. What you do with it is up to you.
Explore the State of the Evidence database at bcpp.org/evidence
Bibliography
[1] Breast Cancer Prevention Partners. “Honoring Nancy Evans.” Accessed February 2026. https://www.bcpp.org/nancy-evans/.
[2] Gray, Janet M., Sharima Rasanayagam, Connie Engel, and Jeanne Rizzo. “State of the Evidence 2017: An Update on the Connection between Breast Cancer and the Environment.” Environmental Health 16, no. 1 (2017): 94. https://doi.org/10.1186/s12940-017-0287-4.
[3] Breast Cancer Prevention Partners. “Year in Review 2017.” Accessed February 2026. https://www.bcpp.org/about-us/press-releases-and-statements/year-review-2017/.
[4] National Institute of Environmental Health Sciences. “Breast Cancer.” Accessed February 2026. https://www.niehs.nih.gov/health/topics/conditions/breast-cancer.
[5] Breast Cancer Prevention Partners. “About BCPP.” Accessed February 2026. https://www.bcpp.org/.
[6] Roell, Kyle R., Devon M. Reif, and Rebecca C. Fry. “Cumulative Environmental Quality Is Associated with Breast Cancer Incidence Differentially by Summary Stage and Urbanicity.” Scientific Reports 13 (2023). https://doi.org/10.1038/s41598-023-45693-0.
