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Disinfection byproducts

Vast majority are without
health standards in tap water

Scientists have detected more than 600 chemicals in tap water that are unwanted byproducts of disinfection. Many of these chemicals form when disinfectants like chlorine, chlorine dioxide, ozone, or chloramines, react with organic matter in the water that typically originates from poorly controlled erosion and runoff from agricultural, urban, and sprawl areas. EPA research has shown that when utitilies reduce levels of handful of disinfection byproducts that are regulated in tap water, they are not necessarily reducing, and may even be increasing, levels of other harmful disinfection byproducts (EPA 2002):

Results revealed the presence of many of the high priority DBPs in the waters sampled. Important observations included finding the highest levels of iodo-trihalomethanes (THMs) at a plant that used chloramination without pre-chlorination. Levels of individual iodo-THMs ranged from 0.2 to 15 µg/L. Another important observation involved finding the highest concentration of dichloroacetaldehyde at a plant that used chloramine and ozone disinfection. Therefore, although the use of alternative disinfectants minimized the formation of the four regulated THMs, certain dihalogenated DBPs and iodo-THMs were formed at significantly higher levels than in waters treated with chlorine. Thus, the formation and control of the four regulated THMs is not necessarily an indicator of the formation and control of other halogenated DBPs, and the use of alternative disinfectants does not necessarily control the formation of all halogenated DBPs, and can even result in increased concentrations of some. Moreover, many of these halogenated DBPs—including certain dihalogenated and brominated species—were not studied in the ICR.

Studies documenting over 600 disinfection byproducts in tap water

Gonzalez, A. C., S. W. Krasner, H. Weinberg, and S. D. Richardson. Determination of newly identified disinfection by-products in drinking water. Proceedings of the American Water Works Association Water Quality Technology Conference, American Water Works Association: Denver, CO, 2000.

Krasner, S. W., R. Chinn, S. Pastor, M. J. Sclimenti, S. D. Richardson, A. D. Thruston, Jr., and H. S. Weinberg. Relationships between the different classes of DBPs: formation, speciation, and control. Proceedings of the American Water Works Association Water Quality Technology Conference, American Water Works Association: Denver, CO, 2002.

Krasner, S. W., S. Pastor, R. Chinn, M. J. Sclimenti, H. S. Weinberg, and S. D. Richardson. The occurrence of a new generation of DBPs (beyond the ICR). Proceedings of the American Water Works Association Water Quality Technology Conference, American Water Works Association: Denver, CO, 2001.

Onstad, G. D., H. S. Weinberg, S. W. Krasner, and S. D. Richardson. Evolution of analytical methods for halogenated furanones in drinking water. Proceedings of the American Water Works Association Water Quality Technology Conference, American Water Works Association: Denver, CO, 2000.

Onstad, G. D., and H. S. Weinberg. Improvements in extraction of MX-analogues from drinking water. Proceedings of the American Water Works Association Water Quality Technology Conference, American Water Works Association: Denver, CO, 2001.

Richardson, Susan D. 1998. Drinking water disinfection byproducts. In Encyclopedia of Environmental Analysis and Remediation, Robert A. Myers, ed. John Wiley & Sons, Inc.

Richardson, Susan D., Alfred D. Thruston, Jr., Chaim Rav-Acha, Ludmila Groisman, Inna Popilevsky, Olga Juraev, Victor Glezer, A. Bruce McKague, Michael J. Plewa, and Elizabeth D. Wagner. 2003. Tribromopyrrole, Brominated Acids, and Other Disinfection Byproducts Produced by Disinfection of Drinking Water Rich in Bromide. Environ. Sci. Technol. 2003, 37, 3782-3793.

Richardson, Susan D., Alfred D. Thruston, Jr., Tashia V. Caughran, Paul H. Chen, Timothy W. Collette, and Terrance L. Floyd. Identification of New Drinking Water Disinfection Byproducts Formed in the Presence of Bromide. Environ. Sci. Technol. 1999a.

Richardson, Susan D., Alfred D. Thruston, Jr., Tashia V. Caughran, Paul H. Chen, Timothy W. Collette, Terrance L. Floyd, Kathleen M. Schenck, Benjamin W. Lykins, Jr., Guang-Ri Sun, and George Majetich. Identification fo New Ozone Disinfection Byproducts in Drinking Water. Environ. Sci. Technol. 1999b.

Sclimenti, M. J., S. W. Krasner, and S. D. Richardson. The determination of DBPs using a solid phase microextraction (SPME)-GC/ECD technique. Proceedings of the American Water Works Association Water Quality Technology Conference, American Water Works Association: Denver, CO, 2002.

Weinberg, H. S., S. W. Krasner, and S. D. Richardson. Determination of new carbonylcontaining disinfection by-products in drinking water. Proceedings of the American Water Works Association Water Quality Technology Conference, American Water Works Association: Denver, CO, 2001.