Maternal Exposure to Nitrosamines  In Drinking Water During Pregnancy And Indices of Fetal Growth In a Chinese Cohort

Abstract

No human studies have focused on drinking water nitrosamines, a group of emerging unregulated nitrogenous disinfection by-products that exhibits genotoxicity and developmental toxicity in experimental studies. This cohort study included 2457 mother-infant pairs from a single drinking water supply system in central China. The associations of maternal trimester-specific and entire pregnancy exposure of drinking water nitrosamines with indices of fetal growth [birth weight (BW), low birth weight (LBW), small for gestational age (SGA) and preterm delivery (PTD)] were evaluated. Elevated maternal N-nitrosodimethylamine (NDMA) exposure in the second trimester and N-nitrosopiperidine (NPIP) exposure during the entire pregnancy were associated decreased BW and increased risks of PTD [e.g., risk ratio (RR) = 2.16; 95% CI: 1.23, 3.79 and 1.66 for the highest vs. lowest tertile of NDMA; p for trend = 0.002]. Elevated maternal exposure of N-nitrosodiethylamine (NDEA) in the second trimester was associated with increased risk of SGA (RR = 1.80; 95% CI: 1.09, 2.98 for the highest vs. lowest tertile; p for trend = 0.01). Our study detected associations of maternal exposure to drinking water nitrosamines during pregnancy with decreased BW and increased risks of SGA and PTD.

Keywords: Drinking water, Low birth weight, Nitrosamines, Preterm delivery, Small for gestational age