Even low-level exposure to mixtures of chemicals commonly used in cosmetic and personal care products is associated with changes in women’s reproductive hormones, according to a new study in Environment International.
The study of reproductive-aged women, led by George Mason University researchers, suggests exposure to bisphenol A, chlorophenols, benzophenones and parabens often used in sunscreens and other cosmetic and personal care products could impact women’s lifetime risk of hormonally mediated diseases.
Researchers studied 509 urine samples from 143 healthy premenopausal women, who were not using birth control. They measured levels of these environmental chemicals, including antimicrobial preservative parabens and UV filtering benzophenones.
The novel component of this study the report on mixtures of chemicals widely used in personal care products, using multiple measures of exposure across the menstrual cycle. This improves upon research that relied on one or two measures of chemicals, author Anna Pollack, Ph.D., M.P.H., George Mason University assistant professor of Global and Community Health, said in a study-related press release.
Pollack and colleagues not only found that mixtures of chemicals might impact reproductive hormone levels, but also that the relationship between these chemicals and hormones is complicated. Certain chemicals and UV filters seem to decrease reproductive hormones in multi-chemical exposures, whereas exposure to others appear to increased reproductive hormones.
Taking a closer look at the findings: While paraben metabolites were associated with hormones in single chemical models, results from single chemical models did not consistently reach statistical significance.
In the multi-chemical approach, researchers uncovered statistically significant associations between the chemicals and hormone changes. For example, paraben factors, paraben metabolites and BPA factor were linked with increased estradiol. That’s consistent with previous study findings, the authors note.
Phenol and UV filter factors were associated with decreased estradiol when modeled together and separately. This association in the multi-chemical models is new, according to the authors.
Progesterone increased in association with all factors modeled together. The authors write that there have been no previously published associations between multi-chemical models of parabens, benzophenones and phenols related to increased progesterone levels.
Modeled together, phenol and UV filter factors were linked to decreased follicle stimulating hormone (FSH) and luteinizing hormone (LH).
Studying these mixtures of chemicals in widely used products might better mimic real-world exposure, but more work needs to be done to corroborate these results, according to the paper.
“Understanding the relationships of bisphenol, A, chlorophenols, benzophenones and parabens with hormone levels among healthy women is critical to disentangling potential effects on other reproductive and endocrine influenced health outcomes, such as endometriosis, fertility and hormonally influenced diseases,” the authors write.