Urinary levels of dimethoate, bisphenol A and benzo[a]pyrene in first-year students of Hohai University from different geographical regions oleh Yu-Juan Xu, Hong-Liang Gao, He Liu, Ning-Wei Zhao, Qi Cheng, Fu-Rong Zhang, Juan Ye, Ai-Qing Wang, Yan-Jun Dou, Bei Ma, Feng Zhu, Xian-Lin Xu, Chao-Jun Li, Jing Wu, Ning Shen, Bin Xue