Decreased birth weight in relation to maternal urinary trichloroacetic acid levels

The effect of exposure to disinfection by-products (DBPs) during pregnancy on newborn's birth weight has been commonly described in animal studies. However, epidemiological evidence was not consistent.

To investigate the relationship between exposure to DBPs and newborn's birth weight in a Chinese population, we conducted a cross-sectional study in Wuhan, China.

A total number of 398 women who had given birth to a live singleton with a gestational age between 37 to 42 weeks were recruited from a local hospital between November 2008 and May 2009. Basic information for all mothers and newborns was obtained from clinic birth records. Among these subjects, 180 women also gave further information including maternal medical history, social status and water-use behaviors by a face-to-face interview. Urinary creatinine (Cr) adjusted trichloroacetic (TCAA) was used as an exposure biomarker.

No statically significant results were found in the linear regression for both 398 participants and 180 participants who finished questionnaires. However, both the crude and adjusted results showed that the mean birth weight of the subjects in the third and top quartiles of Cr-adjusted urinary TCAA concentrations was decreased compared with those in the lowest quartile. Subjects in the top quartiles had the lowest mean birth weight compared to those in other quartiles. In addition, a weak correlation was observed among 82 subjects between drinking water ingestion and urinary Cr-adjusted TCAA (r=0.23, P=0.04).

Our findings suggested that elevated exposure to DBPs may affect fetal growth. The effect of exposure to DBPs during pregnancy on birth weight still warrants further investigations.