Health Risk Assessment of Drinking Water in Shenzhen, Guangdong Province, China in 2019

Objective To evaluate the human health risk in terms of 13 chemical indicators of drinking water in Shenzhen, China in 2019.

Methods A total of 173 monitoring sites were chosen for the monitoring of drinking water in both wet and dry seasons. Among the conventional monitoring indicators, 13 chemical indicators were selected, and a "four-step" method was used to assess their health risks. A stratified analysis was performed on gender, water sample type, and water season.

Results The carcinogenic risk values of hexavalent chromium, arsenic, and chloroform were between 10^-6 and 10^-4 in the whole population, showing potential carcinogenic risks. The comparison between groups showed that generally females had higher risks than males; the secondary water supply had a significantly higher carcinogenic risk of arsenic than other types of water samples; the wet season had significantly higher carcinogenic risks of arsenic and chloroform than the dry season (P < 0.05). The chronic non-carcinogenic risk values were all less than 1, which were within acceptable limits.

Conclusion In 2019, drinking water in Shenzhen may have certain carcinogenic risks, and hexavalent chromium, arsenic, and chloroform were the main carcinogenic chemicals.