Everyday items like personal care products, cosmetics, certain foods, and medications can contain a family of chemicals called parabens, which disrupt endocrine activity in the human body and have been associated with fertility changes in women.
In a new study, researchers at the Yale School of Public Health used pooled urine samples and untargeted metabolomic analysis to identify four diet-related metabolites – including those from the consumption of smoke flavoring, grapes, and olive oil – that were associated with paraben concentrations in the urine of women enrolled in the Early Pregnancy Study.
Surprisingly, the researchers found no associations between paraben concentrations in urine and metabolites on endocrine-disrupting pathways, contrary to the findings of prior studies. In all, the study found seven metabolites associated with paraben concentrations in urine, four of which were related to dietary intake, and three that were not fully identified, said Ana K. Rosen Vollmar, the study’s lead author, who received her PhD from the YSPH Department of Environmental Health Sciences.
Identifying changes to the urinary metabolome around the time of conception could provide insight into the mechanisms by which parabens may impact fertility, the researchers said. Prior studies have suggested that exposure to the potential reproductive toxicants methylparaben, butylparaben, and propylparaben is associated with longer time to pregnancy, decreased menstrual cycle length, and diminished ovarian reserve.
Diet is a known source of exposure to parabens, which are commonly used as food preservatives due to their antimicrobial and antifungal properties that help to prevent spoilage. They are also used in cosmetics and medications. Parabens are heat-resistant, odorless, and tasteless.
Led by Caroline Johnson, associate professor of epidemiology (environmental health sciences), the study is distinct in its detailed control of potential confounding factors and focused investigation into the relationship between paraben exposure and the urinary metabolome in women seeking to conceive. The researchers said their decision to use both targeted and untargeted metabolomic analysis was key to the novel findings.
“These findings underscore a potentially important connection between diet and paraben exposure," the researchers said, with more research needed to understand how parabens enter the food supply, and which food products are major contributors to paraben exposure.
Ana K. Rosen Vollmar, Nicholas J. W. Rattray, Yuping Cai, Abhishek Jain, Hong Yan,
Nicole C. Deziel, Antonia M. Calafat, Allen J. Wilcox, Anne Marie Z. Jukic, Caroline H.
Johnson, Urinary paraben concentrations and associations with the periconceptional urinary
metabolome: untargeted and targeted metabolomics analyses of participants from the
Early Pregnancy Study, Environmental Health Perspectives, Sept. 13, 2023.