New contaminant found in drinking water raises health concerns

A new chemical compound, the chloronitramide anion, has been identified in US drinking water, raising alarms among researchers and public health officials. Although this contaminant has been known to form in chlorinated water since the 1980s, a collaborative study by Swiss and American researchers has only recently clarified its presence and potential risks.  

The chloronitramide anion, chemically represented as Cl–N–NO₂⁻, emerges as a byproduct when chloramines, often used as disinfectants, decompose. This discovery is particularly concerning because the compound has been found in all samples of chloraminated drinking water tested across the United States, with average concentrations of 23 micrograms per liter, and in some instances, nearly 100 micrograms per liter, exceeding the regulatory limits for disinfection by-products, which typically range from 60 to 80 micrograms per liter.  

Chloramines are commonly employed to disinfect drinking water and protect public health against waterborne diseases such as cholera and typhoid fever. Approximately 113 million people in the U.S. rely on chlorinated water for their daily consumption. Despite the benefits of chloramination, the newly identified chloronitramide anion raises questions about the safety of this widely used disinfectant method.  

The research team highlights the need for further investigation into the toxicity of chloronitramide. While its health effects are not yet fully understood, its prevalence and structural similarities to other known toxic compounds warrant urgent scrutiny.  

Interestingly, while chloraminated drinking water is prevalent in North America, it is not commonly practiced in Switzerland. This allowed researchers to use Swiss tap water as a control sample, confirming the absence of chloronitramide in those supplies.

 Although the current study primarily focused on US water systems, countries like Italy, France, and Canada that also utilize chloramination could potentially face similar risks. However, it’s important to note that bottled water may not be a guaranteed solution; in Italy, for example, tap water is subjected to chlorine-based treatments, which are regulated for safety. A report from Italy's National Center for Water Safety indicates that tap water meets microbiological and chemical health standards in over 99% of cases.  

As concerns about water safety continue to grow, the discovery of chloronitramide anion highlights the need for ongoing monitoring and research to ensure the safety of drinking water worldwide.    

Source:  

Science