Fruit and vegetable intake influences the association between exposure to polycyclic aromatic hydrocarbons and a marker of oxidative stress in pregnant women

Background/Objectives: Exposure to polycyclic aromatic hydrocarbons (PAHs) during pregnancy is known to increase oxidative stress, which may influence pregnancy outcomes and health of the child. Subjects/Methods: This study investigated whether fruit and vegetable intake modifies the relationship between exposure to PAHs and oxidative stress status during pregnancy. Urinary levels of 2-naphthol and 1-hydroxypyrene (biomarkers of exposure to PAHs), and malondialdehyde (MDA; a biomarker of oxidative stress) were analyzed in 715 pregnant women at 12-28 weeks of gestation. The dietary antioxidant intake during pregnancy was estimated using the 24-h recall method. Urinary 2-naphthol, 1-hydroxypyrene and MDA levels were analyzed by high-performance liquid chromatography-fluorescence detection. Results: The urinary MDA level was positively correlated with the 2-naphthol level (r=0.255, P<0.001) and 1-hydroxypyrene level (r=0.240, P<0.001). Multiple regression analysis after adjustment for covariates revealed that the urinary 1-hydroxypyrene level was positively associated with the MDA level; these positive associations only existed in pregnant women, with either the fruit and vegetable intake or the vitamin C intake in the first tertile (<390.1 g/day) or in the first and second tertiles (<141.5 mg/day), respectively. Conclusions: These results suggest that an adequate maternal intake of fruit, vegetables and vitamin C is beneficial to the defense against the oxidative stress associated with exposure to PAHs in pregnant women. European Journal of Clinical Nutrition (2011) 65, 1118-1125; doi: 10.1038/ejcn.2011.77; published online 18 May 2011