Non-Regulated Disinfection By-Products in Drinking, Recycled, and Desalinated Water: Occurrence, Toxicological Relevance, and Control Strategies

Year Initiated: 2017
Year Completed: Ongoing


Since the discovery of trihalomethanes (THMs) in drinking water in the early 1970s, disinfection byproducts (DBPs) have become a major driver for United States regulations. To date, more than 600 DBPs have been identified in drinking waters, but only 11 DBPs (4 THMs and 5  haloacetic acids [HAAs], bromate and chlorite) are currently regulated. However, new research shows that certain non-regulated DBPs are substantially (orders of magnitude) more toxic than the currently regulated DBPs. To develop information to inform regulatory agencies, assist utilities in preparing for future regulations, and protect public health, WRF initiated this Focus Area in 2017.


Focus Area Objectives

  1. Develop a better understanding and identify the factors that impact the formation of non-regulated DBPs during water treatment processes.
  2. Develop control strategies that minimize the formation of regulated DBPs while preventing the formation of non-regulated DBPs of potential health concern.
  3. Identify sources of bromide, iodide, and dissolved organic nitrogen (DON), and develop removal strategies.
  4. Provide guidance to utilities to comply with regulations while minimizing unintended consequences.


TAC Members

Steve Via, AWWA; Stuart Krasner, MWDSC; Tanju Karanfil, Clemson University; Zaid Chowdhury, Garver; Ben Stanford, Hazen & Sawyer; Scott Summers, CU-Boulder; Michael Hotaling, Newport News; Paul Westerhoff, ASU; Jonathan Pressman, EPA


Staff Lead

Djanette Khiari,, 303.734.3478


Focus Area Project Timeline and Value

OccurrenceControl StrategiesHealth EffectsPrecursor Control20172018201920202021Total Project Value
 X X#4711 - Occurrence Survey of Bromide and Iodide in Water Supplies


     #4916 - The Impact of Pre-Oxidation and GAC Treatment on DBP Formation and Overall Toxicity in Drinking WaterTBD
 X X Future Project: Bromide and Iodide Removal TechnologiesTBD
 X X Future Project: Brominated HAN and other DBPs Formation & ControlTBD
XXXXFuture Project: Risk Reduction in DBP Exposure:  Past, Present, and Future TBD
X X 


Future Project: Development of a Human Health Relevant DBP Bioassay in Real Drinking WatersTBD
Cumulative Project Value for Focus Area: $300,000


Projects Funded Outside of the Focus Area Program that meet a Focus Area