Health risk study of cadmium, chromium, lead and arsenic in reservoir water of Changzhou, China

Accurately assessing the health risks of human exposure to heavy metals via water is of great importance for performing targeted health risk prevention measures. To better understand the concentration characteristics and potential harm to human health of cadmium, chromium, lead and arsenic in the main drinking water-type reservoirs of Changzhou city, we collected samples from the Haidi Reservoir, Dongjin Reservoir, Xinfushan Reservoir, Maodong Reservoir and Xiangyang Reservoir of Changzhou in the summer of 2019. The results showed that the daily average comprehensive exposure level of metals was much lower than the provisional tolerated daily intake (PTDI), i.e., Cd: 1 µg kg−1 d−1; Cr: 3 µg kg−1 d−1; Pb: 3.57 µg kg−1 d−1; and As: 2.14 µg kg−1 d−1. The comprehensive non-carcinogenic risk levels of four metals under water-drinking exposure and water-skin exposure routes ranged from 4.68E − 3 to 1.69E − 1, and the carcinogenic risk ranged from 2.09E − 5 to 7.30E − 5, which were all at acceptable risk levels. Although lead and chromium were present at acceptable health risk levels, they still represented the main pollutants of potential health risk in the local water environment from a non-carcinogenic or carcinogenic perspective, and they should be listed as the primary targets for water environmental risk management.