Disinfection Byproducts Webinar: Inorganic Chloramine

• March 25, 2025
• The webinar recording will be posted as soon as possible following the webinar.

About the Webinar

Advancing the Story of Inorganic Chloramine Decomposition and Identifying Chloronitramide Anion

This presentation will discuss research that has expanded our knowledge of inorganic chloramine decomposition chemistry. Initially, the research identified the "unidentified intermediate" of chloramine decomposition as nitroxyl, leading to an updated understanding of dichloramine decomposition and a revised pathway for N-nitrosodimethylamine (NDMA) formation in chloraminated drinking water. Next, the research identified the "unidentified product" of chloramine decomposition, which was first reported to exist over 40 years ago, as chloronitramide anion. Chloronitramide anion is expected to form in all chloraminated drinking waters at concentrations in the low to mid μg/L range (i.e., 10s-100s) because it results from inherent chloramine instability; therefore, an external precursor chemical is not required for chloronitramide anion formation. Finally, chloronitramide anion was detected in 40 samples from 10 chloraminated drinking water systems in the US, but not from ultrapure water or water treated without chlorine.

This work summarizes results from three recently published research articles: One in Science and two in Environmental Science & Technology.

Dave Wahman, EPA Office of Research and Development. David G. Wahman is a registered Professional Engineer with over 30 years of experience. He received his B.S. in civil engineering from Rose-Hulman Institute of Technology, an MSE in environmental and water resources engineering, and a Ph.D. in civil engineering from the University of Texas at Austin, followed by a post-doctoral fellowship at EPA before accepting a permanent position as a research environmental engineer. His research interests include disinfectant water chemistry, distribution system water quality, applying modeling and developing applications to understand drinking water treatment and distribution system issues, and per- and polyfluoroalkyl substances (PFAS).

Julian Fairey, University of Arkansas. Julian Fairey is an associate professor in the Department of Civil Engineering at the University of Arkansas. He has an undergraduate degree from the University of Alberta and an M.S. and a Ph.D. from the University of Texas at Austin, all in civil and environmental engineering. His lab group aims to develop strategies to identify and curb disinfection byproducts in drinking water, sampling devices for PFAS quantitation at trace levels, and fluorescence sensor systems for early detection of nitrification in drinking water distribution systems.