title: Concentration, chlorination, and chemical analysis of drinking water for disinfection byproduct mixtures health effects research: U.S. EPA's Four Lab Study.
abstract: The U.S. Environmental Protection Agency's "Four Lab Study" involved participation of researchers from four national Laboratories and Centers of the Office of Research and Development along with collaborators from the water industry and academia. The study evaluated toxicological effects of complex disinfection byproduct (DBP) mixtures, with an emphasis on reproductive and developmental effects that have been associated with DBP exposures in some human epidemiologic studies. This paper describes a new procedure for producing chlorinated drinking water concentrate for animal toxicology experiments, comprehensive identification of >100 DBPs, and quantification of 75 priority and regulated DBPs. In the research reported herein, complex mixtures of DBPs were produced by concentrating a natural source water with reverse osmosis membranes, followed by addition of bromide and treatment with chlorine. By concentrating natural organic matter in the source water first and disinfecting with chlorine afterward, DBPs (including volatiles and semivolatiles) were formed and maintained in a water matrix suitable for animal studies. DBP levels in the chlorinated concentrate compared well to those from EPA's Information Collection Rule (ICR) and a nationwide study of priority unregulated DBPs when normalized by total organic carbon (TOC). DBPs were relatively stable over the course of the animal studies (125 days) with multiple chlorination events (every 5-14 days), and a significant portion of total organic halogen was accounted for through a comprehensive identification approach. DBPs quantified included regulated DBPs, priority unregulated DBPs, and additional DBPs targeted by the ICR. Many DBPs are reported for the first time, including previously undetected and unreported haloacids and haloamides. The new concentration procedure not only produced a concentrated drinking water suitable for animal experiments, but also provided a greater TOC concentration factor (136×), enhancing the detection of trace DBPs that are often below detection using conventional approaches.
authors.affiliation: National Risk Management Research Laboratory, US EPA, Cincinnati, Ohio 45268, USA.
authors.forename: Jonathan G
authors.initials: JG
authors.lastname: Pressman
authors.forename: Susan D
authors.initials: SD
authors.lastname: Richardson
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Speth
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Miltner
authors.forename: Michael G
authors.initials: MG
authors.lastname: Narotsky
authors.forename: E Sidney
authors.initials: ES
authors.lastname: Hunter
authors.forename: Glenn E
authors.initials: GE
authors.lastname: Rice
authors.forename: Linda K
authors.initials: LK
authors.lastname: Teuschler
authors.forename: Anthony
authors.initials: A
authors.lastname: McDonald
authors.forename: Shahid
authors.initials: S
authors.lastname: Parvez
authors.forename: Stuart W
authors.initials: SW
authors.lastname: Krasner
authors.forename: Howard S
authors.initials: HS
authors.lastname: Weinberg
authors.forename: A Bruce
authors.initials: AB
authors.lastname: McKague
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Parrett
authors.forename: Nathalie
authors.initials: N
authors.lastname: Bodin
authors.forename: Russell
authors.initials: R
authors.lastname: Chinn
authors.forename: Chih-Fen T
authors.initials: CF
authors.lastname: Lee
authors.forename: Jane Ellen
authors.initials: JE
authors.lastname: Simmons
mesh_terms: D004202:Disinfectants / Q000009:adverse effects / Q000032:analysis* / Q000737:chemistry; D018570:Risk Assessment; D014481:United States; D014484:United States Environmental Protection Agency; D014881:Water Supply
chemical_list: D004202:Disinfectants