The relationship between skincare product ingredients and breast cancer risk is an emerging area of concern, though evidence remains mixed and more research is needed.
Parabens: These preservatives have been detected in 99% of breast tissue samples examined [[1], [2]]. Animal studies show parabens at FDA-acceptable levels increased mammary tumors and metastases in mice [3]. Laboratory research demonstrates parabens can enable multiple cancer hallmarks in breast cells, including increased proliferation and invasive activity [5]
Phthalates: A Danish study of over one million women found high cumulative exposure to dibutyl phthalate was associated with increased risk of estrogen receptor-positive breast cancer [7]. However, epidemiological evidence is inconsistent, with some studies showing associations and others finding none [8]
UV Filters: Common sunscreen ingredients including benzophenone-3, homosalate, and octyl-methoxycinnamate increase breast cancer cell proliferation in laboratory studies [[10], [11]]. UV filters have been detected in human breast tissue, with benzophenone-3 found in 69% of samples and octyl-methoxycinnamate in 74% [15]
Bottom line: While laboratory and animal studies show concerning effects, human epidemiological evidence is limited and inconsistent. Current evidence suggests these compounds may interfere with endocrine targets relevant to breast cancer development [1]. Choosing products labeled paraben-free and phthalate-free may be a reasonable precautionary approach while research continues.
References
[1] Giulivo, Monica, Mariana Lopez de Alda, Ethel Capri, and Damia Barceló. “Human Exposure to Endocrine Disrupting Compounds: Their Role in Reproductive Systems, Metabolic Syndrome and Breast Cancer. A Review.” Environmental Research 151 (November 2016): 251–264.
[2] Barr, Lester, Gabriella Metaxas, Caroline A. J. Harbach, Lori A. Savoy, and Philippa D. Darbre. “Measurement of Paraben Concentrations in Human Breast Tissue at Serial Locations across the Breast from Axilla to Sternum.” Journal of Applied Toxicology 32, no. 3 (March 2012): 219–232.
[3] Manservisi, Fabiana, Simona Panzacchi, Luciano Bua, Ilaria Palma, Francesca Falcioni, Eva Tibaldi, Michela Manservigi, et al. “Chronic Exposure to Low Levels of Parabens Increases Mammary Cancer Growth and Metastasis in Mice.” Endocrinology 164, no. 3 (March 2023): bqad007.
[4] Darbre, Philippa D., and Philip W. Harvey. “Parabens Can Enable Hallmarks and Characteristics of Cancer in Human Breast Epithelial Cells: A Review of the Literature with Reference to New Exposure Data and Regulatory Status.” Journal of Applied Toxicology 34, no. 9 (September 2014): 925–938.
[5] Erichsen, Andreas K., Peder P. Dybdahl, Mette Sørensen, Søren Friis, and Deirdre P. Cronin-Fenton. “Phthalate Exposure and Breast Cancer Incidence: A Danish Nationwide Cohort Study.” Journal of Clinical Oncology 37, no. 21 (July 2019): 1800–1809.
[6] Létal, A., M. Kvasnicova, J. L. Murin, and N. Navarro Cremades. “Role of Phthalates in Breast Cancer Initiation, Progression and Drug Resistance: A Scoping Review and Recommendations.” Cancer Epidemiology 96 (February 2025): 102691.
[7] Krause, Margret, Anja Klit, Majken Blomberg Jensen, Tina Soeborg, Hanne Frederiksen, Martin Schlumpf, Walter Lichtensteiger, Niels E. Skakkebaek, and Katharina M. Main. “Sunscreens: Are They Beneficial for Health? An Overview of Endocrine Disrupting Properties of UV-Filters.” International Journal of Andrology 35, no. 3 (June 2012): 424–436.
[8] Schlumpf, Margret, Barbara Cotton, Martin Conscience, Vreni Haller, Béatrice Steinmann, and Walter Lichtensteiger. “In Vitro and In Vivo Estrogenicity of UV Screens.” Environmental Health Perspectives 109, no. 3 (March 2001): 239–244.
[9] Darbre, Philippa D. “UV Filters in Human Breast Tissue: Analytical Method and First Results.” Journal of Applied Toxicology 33, no. 11 (November 2013): 1263–1273.