G. Wayne Sovocool, Ph.D.
Environmental Chemistry, Environmental Sciences, NERL/ORD
EXPERTISE: Structural determination and measurement of synthetic and naturally occurring organic chemicals, especially, biologically active compounds, metabolites, chemical transformation products and biomarker compounds, by mass spectrometric techniques, at trace levels in environmental and biological samples. Application of advanced mass spectrometric techniques for the characterization of chemical indicators of exposure, biological changes, and environmental status.
INDIVIDUAL RESEARCH MISSION: Advanced mass spectrometric techniques should be employed in a major, focused research program on the recognition, characterization, and measurement of chemical indicators of exposure and ecological change that currently cannot be measured. Such chemical indicators may include: (1) residues, transformation products, or metabolites of anthropogenic or natural compounds; (2) altered products of natural metabolism; (3) biomarkers of possible genotoxic effects (as DNA adducts); (4) biomarkers of exposure and dosimetry (as protein adducts); (5) biological molecules of communication (semiochemicals) for within- and between-species information exchange; (6) natural toxins, for complete risk assessment, and as indicators of ecological stress.
SIGNIFICANCE/RELEVANCE OF RESEARCH IN RISK ASSESSMENT PARADIGM: A primary goal of the EPA Office of Research and Development (ORD) Strategic Plan is the reduction of uncertainties associated with assessing risk. Unfortunately, low-concentration species often pose the most risk because of high toxicity or other factors, and detection limits of methods that separately measure the relevant species are therefore often inadequate to assist risk assessment. A goal of this research is to develop methods that meet Agency needs to assess human and environmental exposure and risk.
ORD is currently developing a comprehensive strategy for its ecological research. A primary goal, consistent with the risk assessment paradigm, is to provide the means to evaluate the relative vulnerability of ecosystems to multiple stressors via multiple pathways. The ecological chemistry research program being developed here will further this goal by providing baseline and trends data on the distribution of both known and unrecognized chemical stressors at selected ecological sites.
The identification and measurement of chemical hazards to humans and the environment is essential to assessing risk. Advanced mass spectrometric techniques have the sensitivity and structural information content to play a critical role in these identifications and measurements. Development of methods for environmental chemical analysis must necessarily be a continual process because these methods serve as the foundation for all data collected under regulatory programs and also serve as key elements in assessing risk to human and ecological health. These methods serve as the foundation for collection of all environmental status and trends data for the determination of transport, fate, and distribution of chemicals in air, water, soil, sediments, wastes, biota, and tissues. These methods will enable the Agency to monitor the nation's environmental health with better confidence. The activities supported by these methods include environmental monitoring and ecological surveys (e.g., early warning of health/ecological effects); and human/health surveys.
SIGNIFICANT PIONEERING CONTRIBUTIONS:
|Developed an analytical tool combining mass spectral interpretation, sample history, literature searching, and chemical reactivity reasoning that permits the ca. 23 million known chemical substances reported by Chemical Abstracts to be searched, rather than the ca. 300,000 unique mass spectra of compounds present in libraries of mass spectra throughout the world. Most MS libraries significantly duplicate each other and cannot identify the vast number of chemical compounds introduced into the environment and which are not contained in the libraries. This technique can also indicate if the compound is an entirely new one, or present in the literature.|
|Used GC/HRMS to identify previously unrecognized chemical compounds deriving from Superfund Sites so that a more complete risk assessment could be made.|
|Used GC/MS to assess human exposure to foreign compounds in composite human adipose tissue samples.|
|Discovered trans-nonachlor, a component of Technical Chlordane, as a marker of chlordane exposure in human adipose and blood samples and in the environment.|
|Recognized new metabolites of Chlorpyrifos, and lindane.|
Found potent acetylcholinesterase inhibiting organopyrophosphates among the decomposition products of Diazinon in several human poisoning cases.
|Identified brominated biphenyls in adipose tissue samples representative of the general population.|
|First use of the "ortho effect" combined with retention indices to provide structural information of bromine positions in brominated biphenyls.|
|Contributed to methods development for monitoring Kepone in human tissue, water and soil after the Hopewell, VA, spill; identified a Kepone reduction product.|
|Screened Love Canal residents' blood samples by GC/MS and found
Provided verification of identity and purity for pesticide standards used in Agency measurement programs.
|Supported Agency monitoring efforts for dioxins at Times Beach.|
|Used retention indices to determine that synthesized standards of three chlorinated dioxins had incorrect structural assignments and corrected these.|
|Provided the initial recognition of bromochlorinated dioxins and furans in fly ash emissions.|
|Developed a correlation of structure with retention indices for determining all chloro-, bromo-, and bromochloro-dioxins.|
|Investigated bromodibenzofuran and bromodioxin formation in industrial plastics containing brominated fire retardants, including bromodiphenyl ethers.|
|Developed methods for assigning structures to unidentified compounds whose mass spectra are not present in libraries.|
|Verified trace-level, high resolution mass spectrometric measurements of chlorinated dioxins and furans resulting from a municipal incinerator; this required the development of special techniques for correcting for chlorinated ether interference with the chlorinated furans.|
|Assessed the performance of the Superfund Contract Laboratory Program on the identification of tentatively identified compounds and provided suggestions for improvement.|
IMPACT OF CONTRIBUTIONS ON SCIENTIFIC/REGULATED COMMUNITY:
||Mass spectrometric identifications of previously unidentified compounds at Superfund Sites in Massachusetts, Florida, and New Jersey have permitted new risk assessments to be made of these sites.|
||The data on chlordane and its metabolites were used as marker compounds of exposure by the scientific community and by the Agency in the banning of this product.|
|In providing GC/MS confirmation/identification of organochlorine pesticides, PCBs and metabolites in adipose tissue and blood samples as part of the National Human Monitoring Program for Pesticides, the scientific community received rigorous GC/MS confirmation of exposures previously detected as GC/EC peaks.|
|The Agency received legally defensible confirmations of human exposure to foreign compounds. The findings on Diazinon transformation products have been cited in a number of legal cases involving poisoning by decomposed Diazinon. This provided the identification of active human poisoning agents and provided new marker compounds for recognizing certain kinds of exposure.|
|The work on the authentication of analytical standards provided for environmental monitoring by the academic community and the EPA.|
|The Agency Dioxin/Furan Protocol Review Panel, ensured that the Agency had reliable data on bromo-dioxin and bromo-furan formation in brominated fire retardants.|
|Quality data were assured for the assessment of the impact of chlorinated dioxin/furan emissions on a community.|
||Dr. Andrew H. Grange (high resolution mass spectrometry, structure elucidation, MS/MS and HRMS with LC/MS, Regional support)|
|Mr. Stephen M. Pyle (ion-trap GC/MS of volatile and semi-volatile compounds, correlation of GC/MS results with boiling points)|
|Ms. Tammy L. Jones-Lepp (electrospray LC/MS and MS/MS, PPCPs, interpretation of ESI spectra)|
||Christopher Pyott and Stephen Johnson of the State of Massachusetts, Department of Environmental Protection: determination of unrecognized compounds in water samples from the Wilmington, MA Maple Meadow Brook Aquifer.|
|Dr. M.A. Mottaleb, Associate Professor, University of Rajshahi, Bangladesh, while here as a NRC Postdoctoral Associate, studied mass spectrometric techniques used to characterize fish hemoglobin adducts as biomarkers of environmental exposure.|
|Galo Jackson, Remedial Project Manager, South Site Management Branch, Region 4, and Bill Cosgrove, Chief, Organic Chemistry Section, Science & Ecosystem Support Division (SESD) Region 4, EPA Athens, GA: analyzing for unrecognized compounds present in Region 4 samples received from Tower Chemical, Florida, a NPL site previously used for production of dicofol that was suspected of having higher toxicity than present hazard assessments assigned it.|
|Larry Stratton of NEIC: organic compounds from the electrolytic production of magnesium from magnesium chloride.|
|Dr. Daniel Oros: collaboration with the San Francisco Estuary Institute (SFEI): applied our techniques to identifying compounds present in samples from the SF Bay.|
|Mr. Floyd Genicola of the New Jersey EPA: investigating compounds that derive from Superfund sites in New Jersey. Initially begun in response to a EPA Regional request, for identification of unknown compounds possible related to childhood cancer cluster. The compounds were identified as isomers of di-nitrile compounds deriving from acrylonitrile and styrene.|
|Dr. Alvin B. Marcus (negative ions, urinary metabolites, MSn ) [Senior Environmental Employee Program].|
|Confirmation of poisoning agents in suspected pesticide poisoning cases: past collaboration with the Chief Medical Examiner for the State of North Carolina, Arthur J. McBay, M.D.|
|Diazinon poisoning by transformation products: collaborations with Wilson Memorial Hospital, Wilson, NC; Pathologist Robert P. Hadley, M.D., and Alexandria University, Alexandria, Egypt; Professor Salah A. Soliman.|
|GC/MS studies of plant steroid metabolism: collaboration with the Biochemistry Laboratory of the Botany Department, University of North Carolina, Chapel Hill, Professor Aristotle J. Domnas, and Steven A.Warner, Doctoral Candidate.|
|HRMS detection of bromochlorinated- dioxins and -dibenzofurans and PAH in municipal incinerator fly ash samples; FAB-MS of nonvolatile pesticides: collaboration with the University of Nevada at Las Vegas, Dr. Yves Tondeur.|
|Characterization and decomposition studies, by NMR of two isomers of heptachlor epoxide: collaboration with the University of Nevada at Las Vegas, Dr. Richard L. Titus.|
EDUCATION: B.S. degree in Chemistry, 1965, Rochester Institute of Technology. M.S. degree 1967, Ph.D.degree, 1971, in Physical-Organic Chemistry, Cornell University (Professor Richard A. Caldwell, thesis adviser); Dissertation title "Secondary Deuterium Isotope Effects as Mechanistic Probes in Organic Photochemical Reactions." Postdoctoral Research Fellow, U. North Carolina, Chapel Hill, NC; faculty advisor Professor David G. Whitten 1971-1972. Mass Spectral Interpretation Course by Prof. Fred McLafferty, 1974. Laboratory course on purification of proteins, Summer, 1996, Rutgers University. University of Nevada, Las Vegas (UNLV), audited the following to increase awareness in biological sciences: Advanced Topics: Endocrinology (1996); Advanced Topics: Oncology (1997); Biochemistry I and II (1996-7). ACS three day course (5/23/01 to 5/25/01) entitled "Pharmacology for Chemists."
PROFESSIONAL EXPERIENCE: January 1982 - present: Research Chemist, U.S. EPA, National Exposure Research Laboratory, Environmental Sciences Division, Las Vegas, Nevada (and predecessor organizations): Structure determination of organic chemicals, including, biologically active compounds, metabolites, chemical transformation products and biomarker compounds by mass spectrometry at trace-levels in environmental and biological samples. Support for analytical methods development. Verification of pesticide standards and preparation of intercomparison study samples. January 1972 - December 1981: Research Chemist, EPA, Health Effects Research Laboratory (HERL), RTP, NC (mass spectrometry of pesticides and metabolites), Human Adipose Tissue Monitoring Program, Kepone Research Team, North Carolina PCB Spill, Love Canal Human Blood Sample Analyses, Human Poisoning Samples from State Medical Examiner.
ANCILLARY AGENCY RESPONSIBILITIES: Project Officer on the procurement of a high performance instrument (a magnetic sector, double focusing, hybrid mass spectrometer). Have served as Work Assignment Manager on numerous tasks to contractors and as a Project Officer on an Interagency Agreement with NIST. EPA Certified Project Officer. Member of the Agency Dioxin/Furan Protocol Review Panel (1988-1995).
PROFESSIONAL SOCIETIES/ACTIVITIES/OFFICES: American Society for Mass Spectrometry (ASMS). American Chemical Society (ACS). Past Chairman and past Councilor for the Boulder Dam Section (now Southern Nevada Section) of the American Chemical Society.
U.S. EPA Scientific and Technological Achievement Award (STAA) (level III) for 1984:
1998 STAA Received Level II EPA Science Achievement Award in chemistry. Presented jointly with the American Chemical Society April 1999.
NERL Internal Grant Awardee (1996):
"High Performance Mass Spectrometry with CE/ESI-MS and Mass Peak Profiling for Characterizing Chemical Indicators of Environmental Status"
U.S. EPA Bronze Medals for Commendable Service: (1) for assuring the quality of measurements for assessing the impact of dioxin/furan emissions in the vicinity of the Columbus Waste-to-Energy (WTE) municipal incinerator (1997); (2) for developing the Las Vegas Pesticides Quality Assurance Program (1984); (3) for the team effort in developing measurement methods for addressing the impact of the Kepone spill at Hopewell, Virginia (1979).
PUBLICATIONS: 80 publications in peer-reviewed journals; 2 invited book chapters; 16 EPA reports; 6 invited presentations; 9 other scientific presentations; 23 other co-authored presentations.
Selected recent publications:
GRANGE, A. H. AND G. SOVOCOOL. Detection of Illicit Drugs on Surfaces Using Direct Analysis in Real Time (DART)/Time-of-Flight Mass Spectrometry. Rapid Communications in Mass Spectrometry. Wiley InterScience, Silver Spring, MD, 25(9):1271-1281, (2011) Published 5/15/2011.
OSEMWENGIE, L. I. AND G. SOVOCOOL. Rapid Analysis of 209 Chlorinated Biphenyl Congeners using Comprehensive Two-Dimensional Gas Chromatography-Time-Of-Flight Mass Spectrometry in the 1-D Mode followed by the 2-D-Mode. U.S. Environmental Protection Agency, Washington, DC, EPA/600/X-09/012. PUBLISHED 09/04/2009.
GRANGE, A. H. AND G. SOVOCOOL. ION COMPOSITIONS DETERMINED WITH INCREASE SIMPLICITY. Chapter 3, I. Ferrer and E.M. Thurman (ed.), Liquid Chromatography Time-of-Flight Mass Spectrometry. John Wiley and Sons, LTD, , Uk, , 35-56, (2009).
Determination of a Bound Musk Xylene Metabolite in Carp Hemoglobin as a Biomarker of Exposure by Gas Chromatography-Mass Spectrometry Using Selected Ion Monitoring. M.A. Mottaleb, W.C. Brumley, S.M. Pyle, and G. W. Sovocool. J. Anal. Toxicol. (in press).
Formation of nitro musk adducts of rainbow trout hemoglobin for potential use as biomarkers of exposure. M.A. Mottaleb, X. Zhao, L.R. Curtis and G.W. Sovocool. Aquatic Toxicol., 67, 315-324 (2004).
Identifying Compounds Despite Chromatography Limitations: Organophosphates in Treated Sewage. A.H. Grange, L.I. Osemwengie, and G. W. Sovocool. LC.GC North America, 21, 1062-1076 (2003).
Identification of Unanticipated Compounds by High Resolution Mass Spectrometry. A.H. Grange, and G. W. Sovocool. Spectroscopy 18, 12-24 (2003).
Utility of three types of mass spectrometers
for determining elemental compositions of ions formed from chromatographically
separated compounds. A. H. Grange , F. A. Genicola, and G.W. Sovocool.
Rapid Commun. Mass Spectrom., 16,1-14 (2002).
Ion Composition Elucidation (ICE): An Investigative Tool for Characterization and Identification of Compounds of Regulatory Importance. A.H. Grange, L. Osemwengie, G. Brilis, G.W Sovocool. International J. of Environmental Forensics, 2, 61-74 (2001).
Pharmaceuticals and Personal Care Products in the Waters of Lake Mead, Nevada. Snyder, S.A., Kelly, K.L., Grange, A.H., Sovocool, G.W., Snyder, E.M. and Giesy, J.P. Ch 7 in Pharmaceuticals and Personal Care Products in the Environment: Scientific and Regulatory Issues; Daughton, C.G. and Jones-Lepp, T., Eds.; Symposium Series 791; American Chemical Society, Washington, DC, pp. 116-141, (2001).
Identifying Endocrine Disruptors by High Resolution Mass Spectrometry. A.H. Grange, G.W. Sovocool, Ch. 9 in Advances in Analysis of Environmental Endocrine Disruptors, L.H.Keith, T.L. Jones, L.L. Needham, Eds. Symposium Series 747, American Chemical Society, Washington, DC, pp.133-145 (2000).
Capillary Electrophoresis and Capillary Electrochromatography of Organic Pollutants. G.W. Sovocool, W.C. Brumley, and J. R. Donnelly. Electrophoresis, 20:3297-3310, (1999).
Determination of Elemental Compositions by High Resolution Mass Spetrometry
Without Mass Calibrants. A. H. Grange and G.W. Sovocool.
Rapid Comm. In Mass Spectrom., 13:673-686, (1999).
Mass Peak Profiling from Selected-Ion Recording Data (MPPSIRD) as a Tool for Regulatory Analyses. A. H. Grange and G.W. Sovocool. JAOAC International, 82, 1443-1457, (1999).
Powerful New Tools for Analyzing
Environmental Contaminants: Mass Peak Profiling from Selected-Ion-Recording
Data and a Profile Generation Model. A.H. Grange, W.C. Brumley, G.W.
Sovocool. American Environmental Laboratory,
1998, 10, 1,6-7.
Identification of Pollutants in a Municipal Well Using High Resolution Mass Spectrometry. A. H. Grange, G.W. Sovocool, J. R. Donnelly, F. A. Genicola, and D. F. Gurka. Rapid Comm. In Mass Spectrom. 12, 1161-1169, (1998).
Determination of Elemental Compositions from Mass Peak Profiles of the Molecular Ion (M) and the M+1 and M+2 Ions. A. H. Grange, J. R. Donnelly, G.W. Sovocool, and W.C. Brumley. Analytical Chemistry, 68, 553-560, (1996).
Software-Based Mass Spectral Enhancement to Remove Interferences from Spectra of Unknowns. Nelson R. Herron, Joseph R. Donnelly, and G. Wayne Sovocool. J. Am. Soc. Mass Spectrom., 7, 598-604, (1996).