Distribution of pharmaceuticals and personal care products (PPCP) in surface water of Langat River and its behavior in wastewater treatment plant (WWTP): PPCP as water soluble molecular marker of sewage pollution - Tan, Sin Sing; Zakaria, Mohamad Pauzi; Yaziz, Mohammad Ismail; Halimoon, Nomala (Faculty of Environmental Studies, Universiti Putra Malaysia, 2009)