Phthalate acid esters and polycyclic aromatic hydrocarbons concentrations with their determining factors among Chinese pregnant women: A focus on dietary patterns

Background: Pregnant women are susceptible to adverse health effects associated with phthalate acid esters (PAEs) and polycyclic aromatic hydrocarbons (PAHs), and diet is a significant exposure source. Little is known about the contributions of dietary patterns during pregnancy to the exposure variability of these environmental contaminants.

Objectives: To identify dietary patterns in relation to PAEs and PAHs exposure in the Chinese pregnant population.

Methods: Dietary data and urinary concentrations of environmental pollutants were obtained from 1190 pregnant women in the Tongji Birth Cohort (TJBC). PAEs and PAHs were measured in spot urine samples. Food intake was assessed using a food-frequency questionnaire. Dietary patterns were constructed by principal component analysis (PCA). Through PCA, we also extracted three chemical mixture scores that represent different co-exposure patterns of PAEs and PAHs. Multiple linear regression models were adopted to identify predictors of PAEs and PAHs exposure.

Results: Four dietary patterns were identified by PCA that explained 44.9 % of the total variance of food intake. We found egg-dairy products pattern, whole grain-tuber crop pattern, and meat-aquatic products pattern were positively associated with specific pollutants exposure. In contrast, fruit-nut-vegetable pattern was negatively correlated with PAEs and PAHs exposure. Every SD increase in this pattern score was associated with 14.36 % reduced mono(2-ethyl-5-oxohexyl) phthalate (MEOHP) (95 % CI: -24.50 ~ -2.96, p-trend = 0.01), 10.86 % reduced 2-hydroxynaphthalene (2-OHNap) (95 % CI: -20.07 ~ -0.60, p-trend = 0.04), 19.35 % reduced 9-hydroxyphenanthrene (9-OHPhe) (95 % CI: -34.49 ~ -0.70, p-trend = 0.01), and 8.33 % reduced scores of PAHs group (95 % CI: -15.97 ~ -0.10, p-trend = 0.02). In addition, disposable tableware usage and passive smoking were suggested as potentially modifiable sources of PAEs and PAHs exposure, respectively.

Conclusion: Adhering to egg-dairy products pattern, whole grain-tuber crop pattern, and meat-aquatic products pattern may be related to increased PAEs and PAHs exposure, while following fruit-nut-vegetable pattern seems to correlate with a lower burden of such exposure.