The Jialu River in China has been seriously polluted by the direct discharge of industrial and domestic wastewater.The predominant contaminants of the Jialu River and its adjacent groundwater were recently investigated.However,the potential genotoxic impact of polluted water on human health remains to be clarified.Here,we used human-hamster hybrid (AL) cells,which are sensitive for detecting environmental mutagens.We found that the cytotoxicity and mutagenicity of the groundwater in the Jialu River basin were influenced by the infiltration of the Jialu River.Hydrological periods significantly affected the cytotoxicity,but not the mutagenic potential,of surface and groundwater.Further,the mutagenic potential of groundwater samples located ＜ 1 km from the Jialu River (SM-2 water samples) was detected earlier than that of groundwater samples located approximately 20 km from the Jialu River (SN water samples).Because of high cytotoxicity,the mutagenic potential of water samples from the Jialu River (SM-1 water samples) was not significantly enhanced compared with that of untreated controls.To further assess the mutagenic dispersion potential,an artificial neural network model was adopted.The results showed that the highest mutagenic potential of groundwater was observed approximately 10 km from the Jialu River.Although further investigation of mutagenic spatial dispersion is required,our data are significant for advancing our understanding of the origin,dispersion,and biological effects of water samples from polluted areas.