You are here:
OFFICE OF RESEARCH AND DEVELOPMENT'S FOUR LAB STUDY: TOXICOLOGICCAL AND CHEMICAL EVALUATION OF COMPLEX MIXTURES OF DISINFECTION BY-PRODUCTS (DBPS) AND QUALITY ASSURANCE ACTIVITIES FOR A LARGE U. S. EPA MULTILABORATORY STUDY
Citation:
Hughes, T. J., L K. Teuschler, G Rice, J E. Simmons, E S. Hunter, L D. Claxton, M G. Narotsky, R A. Pegram, S. D. Richardson, AND T F. Speth. OFFICE OF RESEARCH AND DEVELOPMENT'S FOUR LAB STUDY: TOXICOLOGICCAL AND CHEMICAL EVALUATION OF COMPLEX MIXTURES OF DISINFECTION BY-PRODUCTS (DBPS) AND QUALITY ASSURANCE ACTIVITIES FOR A LARGE U. S. EPA MULTILABORATORY STUDY. Presented at QA Managers' Meeting, Duluth, MN, October 15-18, 2002.
Description:
Office of Research and Development's Four Lab Study: Toxicological and Chemical Evaluation of Complex Mixtures of Disinfection By-Products (DBPs), and Quality Assurance Activities for a Large U.S. EPA Multilaboratoty Study
Thomas J. Hughes, Project and QA Manager, Experimental Toxicology Division, NHEERL, RTP, NC; Linda K. Teuschler, Glenn E. Rice, NCEA, Cincinnati, OH; JaneEllen Simmons, Project Leader, Sid Hunter, Larry Claxton, Mike Narotsky, Rex Pegram, NHEERL, RTP, NC; Susan Richardson, NERL, Athens, GA; Thomas F. Speth, Dick Miltner, Kathy Schenck, NRMRL, Cincinnati, OH. Research portion of abstract was previously presented at the EPA Science Forum,
May 2002, Washington, D.C.
RESEARCH
Disinfectants used in the production of drinking water react with naturally occurring organic and inorganic material in the source water to produce disinfection by-products (DBPs). Humans are exposed daily to a complex mixture of DBPs via oral, dermal, and inhalation routes. To date, hundreds of chemically distinct DBPs have been identified, yet as much as 50% of the DBP mass is composed of unidentified chemicals. Epidemiological studies suggest cancer and reproductive/developmental effects are associated with consumption of chlorinated drinking water. However, current single-chemical toxicology studies fail to corroborate epidemiological findings. A current data gap is the toxicological and chemical evaluation of the complex DBP mixture, targeting the endpoints identified in epidemiological studies. To address this gap, EPA's Office of Research and Development (ORD) launched a joint project across its four laboratories. Its design is to: (1) produce concentrates of drinking water samples formed using different disinfectants from the same source water; (2) perform analytical chemistry to characterize the known and unknown DBPs in the mixture and test the mixture's stability; (3) perform in vivo and in vitro toxicological testing; (4) use statistical design and analyses to provide data useful in risk assessment, attributing toxicity to the known and unknown fractions of the complex mixture. This research will be made available to the Office of Water to assist them in decisions on complex mixtures. Progress to date includes a draft research proposal, and trial runs to determine feasibility of a full study. Trail runs have included development of concentration methods and procedures to "spike back" lost volatile DBPs, and have provided evidence of chemical integrity of samples over time, palatability of the water to test animals, and initial results from limited toxicological testing. The next step is to conduct the full study with in vitro tests, a multigenerational reproductive/developmental study and other in vivo studies, to gather extensive toxicological data on relevant health endpoints and to more fully characterize the chemical composition of the complex DBP mixture.
QUALITY ASSURANCE
A Quality Management Systems Review (QMSR) was conducted on the Trial Run portion of the study. Work is presently being conducted to plan the QA activities for the Full Study portion of this large (19 PI) 4-Lab Study. Such a large research study is not common within the EPA. Therefore, novel Quality Assurance approaches have to be developed to address requirements for QMPs (Quality Management Plans), QAPPs (QA Project Plans), data reporting, statistical analyses, data archiving, project audits and TSRs (technical systems reviews).
This is an abstract for presentation, and does not necessarily reflect the opinions nor views of the U.S. Environmental Protection Agency.