Increase of urinary malondialdehyde level by bisphenol A exposure: a longitudinal panel study

Background: To verify oxidative stress as a possible mechanism that establishes a relationship between exposure to bisphenol A (BPA) and adverse health outcomes in the elderly Korean population, we evaluated the relation between visit-to-visit variations in urinary BPA and oxidative stress biomarker. Methods: To assess the relation between BPA and urinary malondialdehyde (MDA) as an oxidative stress biomarker, we used a mixed effect model after controlling for age, sex, BMI, drinking status, exercise, urinary cotinine level, PM10 on lag day 2, and mean temperature and dew point on the day. The relation between exposure to BPA and MDA level by sex of participants and polymorphisms of oxidative stress-related genes (COX2, EPHX1, HSP70-hom, PON1, eNOS, CAT, DRD2, SOD2, and MPO) was also evaluated. Results: A significant association was found for BPA with MDA in both male and female elderly participants (male, beta = 0.19 and rho = 0.0003; female, beta = 0.18 and rho <.0001; and total, beta = 0.18 and rho <.0001). Furthermore, the association of BPA with MDA was found regardless of any genotype of the nine oxidative stress-related genes. Conclusions: The results of our study suggest a strong association of BPA with oxidative stress, not related with sex and oxidative stress-related gene polymorphisms.