Development of water quality criteria for toxic organic pollutants -- Development of emergency water quality standards for heavy metals -- Study of species sensitivity distribution for pollutants -- Study of mixture toxicity and ecological risk of pesticides. The book presents some of the findings of research into China's water quality criteria for toxic pollutants, including heavy metals, PAHs and emerging pollutant. Water quality criteria (WQC) are the scientific basis for establishing water quality standards (WQSs). For a long time, the study of WQC in China has been neglected, so that almost all of China's WQSs were developed based on foreign WQC. This book provides valuable information for environmental management and revision of WQSs. It has been written for researchers and graduate students in the field of environmental science and risk assessors for chemical and pollutants etc. Dr. Zhen-guang Yan is an Associate Professor at the Chinese Research Academy of Environmental Sciences. Dr. Zhengtao Liu is a Professor at the Chinese Research Academy of Environmental Sciences.