Study Title:

Vaginal douching and racial/ethnic disparities in phthalates exposures among reproductive-aged women: National Health and Nutrition Examination Survey 2001-2004.

Study Abstract

Background: Diethyl phthalate (DEP) and di-n-butyl phthalate (DnBP) are industrial chemicals found in consumer products that may increase risk of adverse health effects. Although use of personal care/beauty products is known to contribute to phthalate exposure, no prior study has examined feminine hygiene products as a potential phthalate source. In this study, we evaluate whether vaginal douching and other feminine hygiene products increase exposure to phthalates among US reproductive-aged women.

Methods: We conducted a cross-sectional study on 739 women (aged 20-49) from the National Health and Nutrition Examination Survey 2001-2004 to examine the association between self-reported use of feminine hygiene products (tampons, sanitary napkins, vaginal douches, feminine spray, feminine powder, and feminine wipes/towelettes) with urinary concentrations of monoethyl phthalate (MEP) and mono-n-butyl phthalate (MnBP), metabolites of DEP and DnBP, respectively.

Results: A greater proportion of black women than white and Mexican American women reported use of vaginal douches, feminine spray, feminine powder, and wipes/towelettes in the past month whereas white women were more likely than other racial/ethnic groups to report use of tampons (p < 0.05). Douching in the past month was associated with higher concentrations of MEP but not MnBP. No other feminine hygiene product was significantly associated with either MEP or MnBP. We observed a dose-response relationship between douching frequency and MEP concentrations (p(trend) < 0.0001); frequent users (≥2 times/month) had 152.2% (95% confidence intervals (CI): (68.2%, 278.3%)) higher MEP concentrations than non-users. We also examined whether vaginal douching mediates the relationship between race/ethnicity and phthalates exposures. Black women had 48.4% (95% CI: 16.8%, 88.6%; p = 0.0002) higher MEP levels than white women. Adjustment for douching attenuated this difference to 26.4% (95% CI:-0.9%, 61.2%; p = 0.06). Mediation effects of douching were statistically significant for black-white differences (z = 3.71, p < 0.001) but not for differences between Mexican Americans and whites (z = 1.80, p = 0.07).

Conclusions: Vaginal douching may increase exposure to DEP and contribute to racial/ethnic disparities in DEP exposure. The presence of environmental chemicals in vaginal douches warrants further examination.

Study Information

Environ Health. 2015 Jul 15;14:57. doi: 10.1186/s12940-015-0043-6. PMID: 26174070; PMCID: PMC4502470.

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