NERL Research Abstract EPA's National Exposure Research Laboratory GPRA Goal 2 - Clean and Safe Water APM 54 Significant Research Findings from the Method for the Analysis of Phenolic Contaminants on the Contaminant Candidate List (CCL) Scientific Problem and This project involved research to develop an analytical method for the analysis of phenols in drinking water. The need for this project arose from the recently published Candidate Contaminant List (CCL). The CCL identifies drinking water contaminants that might be regulated by EPA at some future date, and was developed in response to the 1996 amendments to the Safe Drinking Water Act (SDWA). The following phenolic compounds are listed on the CCL: 2-methyl-phenol, 2,4- dichlorophenol, 2,4-dinitrophenol, and 2,4,6-trichlorophenol. An analytical method was needed that could be used to measure the pres- ence of these contaminants in drinking water at concentrations below the levels of health concern. The method will be used for collection of nationwide occurrence data for these contaminants in drinking water and could eventually be used for compliance monitoring under the SDWA, if a determination is made that these phenols should be regu- lated. The research goal was to develop a method for measuring at least the four phenols on the CCL, and, ideally, eight additional phenols that are of environmental interest. The method detection limit goal was 1 |ig/L for each target analyte. The approach involved developing procedures for (1) sample collection and preservation, (2) extraction and concentra- tion of the target analytes from aqueous solution, (3) separation of the analytes chromatographically, and (4) detection and quantification of them. Solid phase extraction techniques were investigated for the extraction of phenols from aqueous samples. Gas chromatography/mass spectrometry (GC/MS) was investigated for the chromatographic separation and detection steps, because the MS is a universal detector and is the only detector sensitive and selective enough to measure all of the desired analytes in one GC analysis. Research Approach National Exposure Research Laboratory — October 2001 ------- Sample preservation and holding time studies were also conducted to evaluate sample shipping and handling procedures. Results and The analytical method developed from this research can be used to Implications measure twelve phenols in drinking water samples. The method detec- tion limits for phenols listed on the CCL range from 0.03 to 0.31|ig/L, depending upon the analyte. These concentrations are below those needed for drinking water monitoring, based upon currently available health effects information. This method is an improvement over other published methods for phenols in the following ways: (1) the solid phase extraction procedure requires the use of significantly smaller volumes of solvent than older, liquid-liquid extraction procedures, (2) use of the mass spectrometer as the detector provides positive identifi- cation of all method analytes without the use of additional confirmatory techniques, (3) additional quality control procedures such as the use of internal standards and surrogates help to ensure the quality of the data, and (4) the sample preservation protocol ensures sample stability between the time of sample collection and analysis. These improve- ments will significantly enhance the use of this methodology in the collection of nationwide occurrence data to support regulatory decision making for chemicals on the CCL. U.S. EPA Method 528, "Determination of Phenols in Drinking Water by Solid Phase Extraction and Capillary Column Gas Chromatography / Mass Spectrometry (GC/MS)," Jean W. Munch. Copies of the method can be requested from: National Exposure Research Laboratory Microbiological and Chemical Exposure Assessment Division Chemical Exposure Research Branch 26 W. Martin Luther King Dr. Cincinnati, OH, 45268-1564 The method will soon be available on the internet at http://www.epa.gov/nerlcwww/ordmeth.htm . Future Research Due to the success of the method development, no further research is planned at this time. However, Method 528 will be proposed as the required analytical method in the Office of Ground Water and Drinking Water's upcoming proposal for the Unregulated Contaminant Monitoring Regulation (June, 2000). When finalized, this regulation will require a nationwide monitoring survey of several thousand drinking water samples at 300 sites for the presence of selected CCL contaminants, including the four phenolic compounds listed above. Occurrence data from this survey will be used in the decision making process for the possible regulation of the phenols listed on the CCL. Research Collaboration and Publications National Exposure Research Laboratory — October 2001 ------- Contacts for For additional information, please contact: Additional Information Jean W Munch US EPA, Office of Research and Development National Exposure Research Laboratory Cincinnati, OH 45268-1564 Phone: 513-569-7465 E-mail: munch.jean@epa.gov National Exposure Research Laboratory — October 2001 ------- |