What it is
Parabens are synthetic preservatives that stop bacteria, mold and yeast from growing in products. A review of their endocrine effects (Nowak et al., 2018) describes them as one of the most popular preservatives in foods, cosmetics, and pharmaceutical products, used worldwide, and notes that they are easily absorbed by the human body. On labels, parabens may appear as methylparaben, ethylparaben, propylparaben, butylparaben, isobutylparaben, isopropylparaben, benzylparaben, phenylparaben or pentylparaben.
Why it is a concern
- Hormone disruption. The same review (Nowak et al., 2018) reports that current literature classifies parabens as endocrine-disrupting chemicals that act on the receptors of hormones such as estrogen. In animal studies, parabens interfere with male and female reproduction and the thyroid system, and some experimental evidence links them to obesity and hormone-related cancers (Food Packaging Forum, 2018). The evidence in people is less settled: the review’s authors note that some effects seen in animals have not yet been confirmed in human studies (Nowak et al., 2018).
- Early signs of breast cancer–related changes. In a 2023 study (Dairkee et al., 2023), healthy women stopped using paraben- and phthalate-containing personal care products for 28 days. Breast tissue samples taken before and after showed a striking reversal of cancer-associated phenotypes, along with a significant drop in urinary parabens and phthalate metabolites. This doesn’t prove parabens cause cancer: the study measured changes in breast cells, not cancer itself, and it examined parabens and phthalates together. The lead investigator described it as a pilot study, and the researchers said it needs to be replicated in a larger study to confirm the results (Environmental Health News, 2023).
- Restricted in the EU. The European Union has banned five parabens from cosmetics: isopropylparaben, isobutylparaben, phenylparaben, benzylparaben and pentylparaben (EU Regulation 1004/2014). The ban was imposed because industry submitted limited or no safety data for them, so the risk to humans couldn’t be evaluated (EU Regulation 358/2014). The EU also caps propylparaben and butylparaben at a combined 0.14% and prohibits them in leave-on products for the nappy area of children under three (EU Regulation 1004/2014). By contrast, the EU’s scientific committee confirmed that methylparaben and ethylparaben are safe at the maximum authorized concentrations (EU Regulation 1004/2014). If you’d rather limit your exposure to endocrine-disrupting chemicals overall, choosing paraben-free products is a simple way to do it.
Where it can be found
Parabens are used as preservatives in cosmetics, pharmaceuticals, and food and beverage processing (Calafat et al., 2010). Exposure is widespread: in a US national survey, methylparaben and propylparaben were detected in 99.1% and 92.7% of urine samples, and differences between groups likely reflect the use of personal care products containing these compounds (Calafat et al., 2010). Common examples include shampoo, deodorant, lotion, nail polish and fragrances (Environmental Health News, 2023).
Label Tip
Scan the ingredient list for any word ending in “-paraben”: methylparaben, ethylparaben, propylparaben, butylparaben, isobutylparaben, isopropylparaben, benzylparaben, phenylparaben or pentylparaben. Also watch for their salt forms, which put “sodium” or “potassium” in front, such as sodium methylparaben, potassium ethylparaben, sodium propylparaben or sodium butylparaben (EU Regulation 1004/2014). Less often, parabens appear under their chemical names, which include “4-hydroxybenzoate” (for example, butyl 4-hydroxybenzoate or propyl 4-hydroxybenzoate).
References
- Nowak K, Ratajczak-Wrona W, Górska M, Jabłońska E. Parabens and their effects on the endocrine system. Mol Cell Endocrinol. 2018;474:238–251. https://pubmed.ncbi.nlm.nih.gov/29596967/
- Dairkee SH, Moore DH, Luciani MG, Anderle N, Gerona R, Ky K, Torres SM, Marshall PV, Goodson WH III. Reduction of daily-use parabens and phthalates reverses accumulation of cancer-associated phenotypes within disease-free breast tissue of study subjects. Chemosphere. 2023;322:138014. https://pubmed.ncbi.nlm.nih.gov/36746253/
- Calafat AM, Ye X, Wong LY, Bishop AM, Needham LL. Urinary concentrations of four parabens in the U.S. population: NHANES 2005–2006. Environ Health Perspect. 2010;118(5):679–685. https://pubmed.ncbi.nlm.nih.gov/20056562/
- Commission Regulation (EU) No 358/2014. https://legislation.gov.uk/eur/2014/358/data.pdf
- Commission Regulation (EU) No 1004/2014. https://eur-lex.europa.eu/eli/reg/2014/1004/oj
- James A. Get phthalates, parabens out of the bathroom drawer to reduce breast cancer risk: Study. Environmental Health News. 2023. https://www.ehn.org/phthalates-and-breast-cancer-2659605676