Ozonation of wastewater treatment leads to the formation of World War I chemical warfare agent

With increasing water scarcity, wastewater treatment has been widely promoted. Among the methods to treat wastewater are ozonation and chlorination. But these create disinfection byproducts, called halonitromethanes, according to new research. The process can turn chemicals in water into toxic chloropicrin, the study claimed. Ozone-treated water has nitromethane, a chemical formed from some drugs containing nitrogen. The drugs are mainly antidepressants and stimulants (ephedrine, methamphetamine, etc). When nitromethane interacts with chlorine — used to make the water drinkable — chloropicrin is formed. It can harm humans body, ranging from eye and skin to the respiratory system. Alternate treatment methods, which uses biologically active carbon instead of chlorine, can prevent chloropicrin formation.