Four Lab Study jump-starts health effects research.

Pressman, JG, SD Richardson, TF Speth, RJ Miltner, MG Narotsky, ES Hunter III, GE Rice, LK Teuschler, A McDonald, S Parvez, SW Krasner, HS Weinberg, AB McKague, CJ Parrett, N Bodin, Ru Chinn, C-FT Lee and JE Simmons. 2010. Concentration, chlorination and chemical analysis of drinking water for disinfection byproduct mixtures health effects research: U.S. EPA's four lab study. Environmental Science and Technology http://dx.doi.org/10.1021/es9039314.

It is not often that scientists from government, academic and private industry team up to address – and solve – a public health problem. An exception to that notion is the "Four Lab Study" – a cadre of North American researchers pulled together to better understand the chemical mix created during the disinfection of drinking water and the possible health impacts on people.

To push research in this area, the scientists developed a method to make contaminated water that closely matches the mixture of byproducts and other chemicals created when drinking water is disinfected. In a recent issue of Environmental Science and Technology, the team reports on how the liquid can be used for health effects research studies and how the concentrate provides for easier detection of the byproducts formed during disinfection.

Using the water, they identified more than 100 chemical byproducts and measured the levels of 75 of the most harmful and highly regulated ones. It was the first time many of the chemicals had ever been detected.

This study is important because it lays the foundation for future research to explore health effects from the degradation products of water disinfection processes, a much needed area of research.

Drinking water disinfection processes often lead to the formation of byproduct chemicals in water; some of these chemicals are known carcinogens and may be associated with health problems. Prior human studies have suggested that exposure to some of the chemicals may have repoductive and developmental effects as well.

The large group of scientists worked together to create the large volumes of water that concentrated and stabilized the disinfection byproducts (DBPs). The existing methods for concentrating organic compounds – namely resin extractions and the use of organic solvents – had hindered previous attempts to produce the large volumes of water needed for these studies.

The new method uses reverse osmosis technology to concentrate natural organic matter in water. This water is then treated with chlorine to form the DBPs. Concentrating, then disinfecting, creates the large volumes of water with more stable DBP products, including chemicals that are typically lost to the air – such as, volatile organic compounds. The mixture was stable for more than 100 days, making the mixture suitable for use in animal studies.

The water was analyzed to determine the primary DBPs and the types and levels were compared to the list of regulated, unregulated priority and unknown chemicals targeted by federal agencies.

From this, they identified many new halogenated disinfection byproducts, including haloacids, haloamides, halofuranones and nonhalogenated DBPs. This finding is important because haloamides in particular are extremely toxic to cells and genes in mammals.