The continuous urbanization and industrialization in many parts of the world and Iran has led to high levels of heavy metal contamination in the soil and then on the surface and groundwater. In this study, the concentrations of 8 heavy metals were determined in forty water samples along distribution drinking water of Khorramabad, Iran. The ranges of heavy metals in this study were lower than EPA and WHO drinking water recommendations and guidelines and so were acceptable. The mean values of CDItotal of heavy metals concentrations in adults were found in the order of Zn > Ba > Pb > Ni > Cr > Cu > Cd > Mo. The health-risk estimation indicated that total hazard quotient (HQing + HQderm) and hazard index values were below the acceptable limit, representing no non-carcinogenic risk to the residents via oral intake and dermal adsorption of water. Moreover, the results of total risk via ingestion and dermal contact showed that the ingestion was the predominant pathway. This study also presents that the carcinogenic risk for Pb, Cr, Cd and Ni were observed higher than the acceptable limit (1 × 10-6). The present study will be quite helpful for both inhabitants in taking protective measures and government officials in reducing heavy metals contamination of urban drinking water. •The data analyzed in this study show a clear situation regarding the quality of drinking water in Khorramabad.•The results of this study can be used to improve and develop the quality of drinking water that directly affects the health of consumers.•The present study will be quite helpful for both inhabitants in taking protective measures and government officials in reducing heavy metals contamination of urban drinking water.

Contamination of surface and groundwater resources to heavy metal due to mining activities is a worldwide major issue because of its probable health risks to local residents. In the present research, we measured the concentrations of As, Cd and Cr in 26 water samples collected from 13 rural areas in the vicinity of mines in Sabzevar, Iran, during January 2019 and estimated potential health risks among local residents. Heavy metal concentrations were analysed using an atomic absorption spectrometer and compared with guidelines set by the WHO. The results showed that As and Cr concentration in drinking water of rural areas in the vicinity of mines were estimated to be in the range of 0.0152 to 0.0220 and 0.0194 to 0.1806 mg/L, respectively, which exceeded the drinking water guidelines recommended by WHO. For cadmium, the concentrations ranged from 0.0003 to 0.0018 mg/L. Total HI (hazard index) values were above one in drinking water of all villages and generally, total HI values for children were much higher than those of adults in each studied area. The total cancer risk values of metals (sum of As, Cd and Cr) for children and adults in all the villages were above the USEPA limit. The CR (carcinogenic risk) values for both children and adults through the oral pathway were found in order of As>Cr>Cd. The findings of health risk assessment of groundwater near the mining area could be valuable for proper management of water resources in the rural areas in particular and to the other mining areas in general.