Spatial assessment of tap-water safety in China

The importance of ensuring access to clean drinking water is manifested in UN Sustainable Development Goals. Here, a national-level assessment of tap-water safety shows spatial variations across China. The disparity is correlated with natural and anthropogenic factors and linked to public health-risk rates. The quality of drinking-water supplies is of fundamental importance to public health and sustainable development. Here, we provide a spatial assessment of the tap-water quality across mainland China. We examine natural and anthropogenic origins of low quality as well as its association with public health risks. By quantifying key indicators, including total organic carbon, ionic conductivity and disinfection by-products (DBPs), we find that precipitation is a crucial factor driving the change of organic matter content and ionic conductivity of tap-water, especially for arid and semi-arid regions. Although the concentration of DBPs is closely related to the organic matter content, the occurrence of highly toxic DBPs is more subject to anthropogenic factors such as economic development and pollution emission. We show that nanofiltration is an effective point-of-use treatment to reduce the adverse effects of DBPs. The present results highlight the potential health hazards associated with low-quality drinking water, suggesting that countries and regions experiencing rapid socioeconomical development might face high levels of DBP toxicity and should consider adoption of sustainability solutions.

Automated summary

The importance of ensuring access to clean drinking water is highlighted in the UN Sustainable Development Goals. A national-level assessment of tap-water safety in China reveals spatial disparities, which are influenced by natural and anthropogenic factors and have implications for public health risks. This study provides a spatial assessment of tap-water quality in mainland China and investigates the natural and anthropogenic origins of low quality and their association with public health risks. Precipitation is found to be a crucial factor driving the change in organic matter content and ionic conductivity of tap-water, especially in arid and semi-arid regions. While the concentration of disinfection by-products (DBPs) is closely related to organic matter content, the occurrence of highly toxic DBPs is more influenced by anthropogenic factors such as economic development and pollution emission. The results emphasize the potential health hazards associated with low-quality drinking water and suggest that rapidly developing countries and regions should consider adopting sustainable solutions.