The team around Chao CHEN from Tsinghua University School of Environmental Sciences has screened 164 water samples from 155 sites in 23 provinces and 44 cities across the country. On average, nitrosamine concentrations were 3.6 fold higher than in comparable studies in the US. As water treatment via chlorination or chloramination of organic nitrogen-containing wastewater can lead to the production of NDMA at potentially harmful levels, better cleaning of factory water may be one way to improve the situation.
China Bio news release, October 14, 2016