Breast Cancer Is No Longer Just About Genes. It’s Also About The Environment.
By Luc ANATO
Ask most breast cancer patients the standard clinical questions, and they will be about genetics, smoking, alcohol consumption. These factors matter. But a different question, broader and harder to pin down, is increasingly pushing its way into the research: the environment a person lives in.
“The environment” covers very different realities: a warming climate, the way a society manages, or fails to manage, its waste, pollution of air, water and soil. These issues are generally treated, in research and in the media, as separate problems, each with its own experts, conferences and funding streams. Yet they are closely linked: the same poorly managed waste can both worsen climate change and expose a human body directly to active substances.
This piece does not attempt to cover that entire field. It focuses on one strand, plastic, because it is the ground I know best, as a practitioner working on waste management and the fight against plastic pollution in West Africa. What does the science say, today, about its link to breast cancer? And what, precisely, do we know about that link in Africa?
What the research has found
Endocrine-disrupting chemicals found in everyday plastics, phthalates above all, are the subject of increasingly precise research. A Taiwanese cohort of nearly 12,000 women followed for twenty years, published in March 2026 in the Proceedings of the National Academy of Sciences, links high phthalate exposure to an increased risk of breast cancer among women with certain metabolic vulnerabilities. A systematic review of 131 epidemiological studies, published in 2021 in Critical Reviews in Toxicology, had already reached converging conclusions on the association between endocrine disruptors and breast cancer.
More recently, researchers have begun finding microplastics directly inside breast tumour tissue itself, rather than only inferring exposure statistically. A 2026 study in the journal Apoptosis documents this direct presence in tumour and peritumoral tissue. Another, published in 2025, describes a precise cellular mechanism: microplastics bound to a protein called ANXA2, found in tumour samples, causing damage to the cells’ mitochondria. Their presence in a tumour does not, by itself, prove they caused it. But it shifts the question from statistical inference to direct observation.
What the research has not found
Scientific rigor requires stating just as clearly what remains undemonstrated. The Long Island Breast Cancer Study Project, a landmark US study mandated by Congress in the 1990s, found no significant link between exposure to certain older organochlorines, such as DDT or PCBs, and breast cancer risk, even among the most exposed women. A 2021 meta-analysis of nine studies and nearly 8,000 cases and controls even found a negative, protective, association for two specific phthalate metabolites.
Plastic is not a uniform block of risk. Some suspected substances show, to date, no demonstrated effect, and it would be dishonest to present all of its derivatives as equally dangerous. The picture that emerges is finer-grained than that, substance by substance, study by study.
What we still don’t know in Africa
One question that the scientific literature itself keeps raising: where are the African studies? A 2025 systematic review in the South African Medical Journal compared epidemiological perspectives on environmental risk factors for breast cancer in Africa and in Western countries. Its conclusion is clear: the vast majority of available studies on the link between endocrine disruptors and breast cancer come from North America and Europe. Data on the African continent remain extremely limited, with most existing work concentrated in South Africa, largely absent elsewhere on the continent.
This gap is not a methodological footnote. A woman in Cotonou or Lagos is not exposed to the same plastics, under the same heat conditions or open-air burning practices, as a woman followed in a North American or Taiwanese cohort. Nothing today allows us to claim that results obtained elsewhere transfer directly here. Nothing allows us to claim the opposite either. Until this question is asked directly on West African ground, with local cohorts and local exposures, the debate between concern and dismissal will keep feeding on data drawn from elsewhere.
What this changes, in practice
This research gap is not a reason to ignore the subject. It is a reason to invest in finding out, in Africa, exactly where things stand. While we wait for that data, two things can already be said without overstatement: plastic is no longer just a waste material accumulating in the environment, part of the research shows it circulating in bodies; and the scientific caution that separates what is proven from what is not yet proven is precisely what makes this conversation credible, rather than turning it into another source of unfounded panic.
Luc ANATO is co-founder of VEDI Action, a sustainability and CSR consulting firm based in Benin, and serves as Benin’s National Focal Point for the International Francophone Coalition Zero Plastic.
Sources:
1. PNAS, March 2026 — https://www.google.com/url?q=https://www.pnas.org/doi/abs/10.1073/pnas.2507008123&source=gmail&ust=1790987285919000&sa=E
2. Critical Reviews in Toxicology, 2021 — https://www.google.com/url?q=https://www.tandfonline.com/doi/full/10.1080/10408398.2021.1903382&source=gmail&ust=1790987285919000&sa=E
3. Apoptosis, 2026 — https://www.google.com/url?q=https://link.springer.com/article/10.1007/s10495-026-02372-5&source=gmail&ust=1790987285919000&sa=E
4. Environmental Pollution, 2025 — https://www.google.com/url?q=https://pubmed.ncbi.nlm.nih.gov/39557355/&source=gmail&ust=1790987285919000&sa=E
5. Long Island Breast Cancer Study Project (NCI) — https://www.google.com/url?q=https://epi.grants.cancer.gov/past-initiatives/libcsp/?datasetID%3D233206&source=gmail&ust=1790987285919000&sa=E
6. International Journal of Environmental Research and Public Health, 2021 — https://www.google.com/url?q=https://doi.org/10.3390/ijerph18052375&source=gmail&ust=1790987285919000&sa=E
7. South African Medical Journal, 2025 — https://www.google.com/url?q=https://samajournals.co.za/index.php/samj/article/view/3696&source=gmail&ust=1790987285919000&sa=E