Exposure of children to BPA through dust and the association of urinary BPA and triclosan with oxidative stress in Guangzhou, China

Both bisphenol A (BPA) and triclosan (TCS) are phenolic compounds widely used in a variety of household applications. These compounds could be released into the environment, enter the human body and cause a series of potential health hazards. Children are sensitive and susceptible to these contaminants. To investigate the potential oxidative DNA damage from exposure to BPA and TCS, ninety six urine samples of children (aged 3-6) and 57 dust samples were collected from a kindergarten in Guangzhou, China. The concentrations of urinary BPA, TCS and 8-hydroxy-20-deoxyguanosine (8-OHdG, a biomarker of oxidative DNA damage) in urine were determined using a liquid chromatography tandem mass spectrometer. The geometric mean concentrations of urinary BPA, TCS and 8-OHdG were 1.08 mu g L-1, 1.34 mu g L-1 and 1.90 mu g L-1, respectively. The results showed that both BPA and TCS exposures were associated with oxidative damage. Significant dose-effects existed between the urinary BPA, TCS levels and the 8-OHdG concentrations. Multiple linear regression analysis showed that one percent increase in BPA and in TCS could generate 0.15% and 0.081% increase in 8-OHdG in urine for children in Guangzhou. We also determined the concentrations of BPA in dust using high performance liquid chromatography. The mean concentration of BPA was 2.86 mu g g(-1) in indoor dust and 3.23 mu g g(-1) in outdoor dust. The dust contributes approximately 9.23% to the urinary BPA exposure for the children. In conclusion, BPA and TCS exposure correlates with oxidative DNA damage.