Faculty Directory

Greg Thoma

Greg Thoma

Director of Research

Professor, Bates Teaching Endowed Professorship in Chemical Engineering


(CHEG)-Chemical Engineering

Phone: 479-575-2422

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Greg Thoma, Ph.D. served as director for research and is currently senior advisor to The Sustainability Consortium, a joint effort of the University of Arkansas and Arizona State University with membership of over 90 national and multinational corporations, governmental organizations and NGOs. The Consortium is focused on measuring and improving the sustainability of consumer goods, including food.  He has represented the Sustainability Consortium on the United Nations Environment Program/Society of Environmental Toxicology and Chemistry Lifecycle Initiative board of directors assisting in coordination of international efforts to mainstream life cycle management in the consumer goods sector.  He has been on the faculty at the University of Arkansas since receiving his Ph.D. in Chemical Engineering in 1994 from Louisiana State University, and is a Registered Professional Engineer in the state of Arkansas. He has held the Ray C. Adam Chair in Chemical Engineering and is currently the Bates Teaching Professor in Chemical Engineering.

Dr. Thoma’s research focuses on the application of chemical engineering principles to find solutions to environmental problems. He is currently lead investigator for a number of life cycle initiatives in the food and agriculture sector including studies on fluid milk, cheese, milk delivery systems, and is project director for a 5-year, $5M USDA multi-university project focused on greenhouse gas mitigation for US swine production. Dr. Thoma also consults on other LCA work at the University of Arkansas focusing on rice, cotton, corn, and sweet corn.  Recently he became the scientific lead for the UNFAO Partnership on the Environmental Benchmarking of Livestock Supply Chains technical advisory group for poultry which is working to create guidance in the application of LCA for assessment of sustainable poultry and egg production. He is currently serving on the steering committee for the Swiss National Science Foundation’s National Research Program titled, “Healthy Nutrition and Sustainable Food Production” that has the goal of promoting healthy nutrition through a safe, high quality food supply, available in sufficient quantity at affordable prices, while minimizing environmental impacts and fostering efficient resource utilization.

  • "US Fluid Milk Beyond Carbon LCA Study," $90,000: University of Michigan (2011-2012)
  • "Estimation of the US Dairy Sector Contribution to the US GHG Inventory," $29,719: Dairy Research Institute (2011)
  • "Comprehensive Life Cycle Assessment for Cheese and Whey Products," $390,809: Dairy Management, Inc.(2009-2011)
  • "Comprehensive Life Cycle Assessment for Fluid Dairy Delivery Systems," $349,984: Dairy Management, Inc.(2009-2011)
  • "Life Cycle Assessment for Dairy Fluid Milk: Beyond Carbon," $93,830: Dairy Management, Inc.(2009-2010)
  • "Life Cycle Assessment for Pork Carbon Footprint," $129,774: National Pork Board (2009-2010)
  • "Life Cycle Assessment of the Retail Supply Chain: Dairy Products," $549,724: Dairy Management, Inc. (2008-2013)
  • "A Robust Process for Biodiesel Production Using Supercritical Methanol," $9,798: U.S. Environmental Protection Agency (EPA) (2008-2009)
  • "ABI: Using Analysis & Microarrays to Determine Remediation of Polycyclic Aromatic Hydrocarbon-Contaminated Soils," $49,700: State of Arkansas (2007-2008)
  • "Special Environmental Project: Design of a Photocatalytic Reactor Using Immobilized Thin TiO2 Films on Quartz Rod," $15,750: Arkansas Department of Environmental Quality (2007)
  • "Development of a bacterial source tracking and apportionment methodology using DNA micro arrays and Luminex micro beads, and its application in the Ozark Plateau," $48,000: Arkansas Biosciences Institute (2005)
  • "Field Demonstration and Tech-Transfer for the Continuous Measurement of Crude Oil Stock Tank Emissions", $41,473: IPEC (2004).
  • “Compound Specific Stable Isotope Technology for Major Questions in Human and Environmental Health Sciences,” $108,000 Arkansas Biosciences Institute (2004)
  • "Use of Earthworms to Accelerate the Restoration of Oil and Brine Impacted Sites," $116,100: IPEC (2003-2005)
  • "Using plants to remediate petroleum contaminated soils", $169,712 IPEC (2003-2004)
  • "Data for Design of Vapor Recovery Units for Crude Oil Stock Tank Emissions," $100,000: IPEC (2003)
  • "Bacterial and Sediment Tracing for Karst Aquifers," $274,000: National Science Foundation (2002- 2005).
  • "Risk Reduction and Soil Ecosystem Restoration in an Active Oil Producing Area in an Ecologically Sensitive Setting", $166,893: DOE (2002-2005)
  • "Using plants to remediate petroleum contaminated soils," $145,298: IPEC (2000-2001).
  • "Bacterial Tracing in Karst Terrain," $55,000: Arkansas Science and Technology Authority (2000 - 2001).
  • "Administrative Services for the Integrated Petroleum Environmental Consortium," $204,000: IPEC (2000-2005)
  • BSChE, University of Arkansas, 1980 
  • MSChE, University of Arkansas, 1986 
  • Ph.D., Chemical Engineering, Louisiana State University, 1994 
  • Kim, D., Thoma, G., Nutter, D., Milani, F., Ulrich, R., & Norris, G. (2013). Life cycle assessment of cheese and whey production in the USA. The International Journal of Life Cycle Assessment, 18(5), 1019–1035. doi:10.1007/s11367-013-0553-9
  • Adom, F., Workman, C., Thoma, G., & Shonnard, D. (2013). Carbon footprint analysis of dairy feed from a mill in Michigan, USA. International Dairy Journal, 31, S21–S28. doi:10.1016/j.idairyj.2012.09.008
  • Asselin-Balençon, A. C., Popp, J., Henderson, A., Heller, M., Thoma, G., & Jolliet, O. (2013). Dairy farm greenhouse gas impacts: A parsimonious model for a farmer’s decision support tool. International Dairy Journal, 31, S65–S77. doi:10.1016/j.idairyj.2012.09.004
  • Matlock, M., Thoma, G., Cummings, E., Cothren, J., Leh, M., & Wilson, J. (2013). Geospatial analysis of potential water use, water stress, and eutrophication impacts from US dairy production. International Dairy Journal, 31, S78–S90. doi:10.1016/j.idairyj.2012.05.001
  • Thoma, G., Popp, J., Nutter, D., Shonnard, D., Ulrich, R., Matlock, M., Kim, D. S., et al. (2013). Greenhouse gas emissions from milk production and consumption in the United States: A cradle-to-grave life cycle assessment circa 2008. International Dairy Journal, 31, S3–S14. doi:10.1016/j.idairyj.2012.08.013
  • Thoma, G., Popp, J., Shonnard, D., Nutter, D., Matlock, M., Ulrich, R., Kellogg, W., et al. (2013). Regional analysis of greenhouse gas emissions from USA dairy farms: A cradle to farm-gate assessment of the American dairy industry circa 2008. International Dairy Journal, 31, S29–S40. doi:10.1016/j.idairyj.2012.09.010
  • Ulrich, R., Thoma, G., Nutter, D., & Wilson, J. (2013). Tailpipe greenhouse gas emissions from tank trucks transporting raw milk from farms to processing plants. International Dairy Journal, 31, S50–S56. doi:10.1016/j.idairyj.2012.09.009
  • Nutter, D. W., Kim, D.-S., Ulrich, R., & Thoma, G. (2013). Greenhouse gas emission analysis for USA fluid milk processing plants: Processing, packaging, and distribution. International Dairy Journal, 31, S57–S64. doi:10.1016/j.idairyj.2012.09.011
  • Thoma, G., Jolliet, O., & Wang, Y. (2013). A biophysical approach to allocation of life cycle environmental burdens for fluid milk supply chain analysis. International Dairy Journal, 31, S41–S49. doi:10.1016/j.idairyj.2012.08.012
  • Popp, J. S., Thoma, G. J., Mulhern, J., Jaeger, A., LeFranc, L., & Kemper, N. (2013). Collecting complex comprehensive farm level data through a collaborative approach: A framework developed for a life cycle assessment of fluid milk production in the US. International Dairy Journal, 31, S15–S20. doi:10.1016/j.idairyj.2012.04.001
  • Leh, M., Matlock, M., Cummings, E., Thoma, G., & Cothren, J. (2013). Measuring ecosystem service change: A case study from a northwest Arkansas dairy farm. International Dairy Journal, 31, S91–S100. doi:10.1016/j.idairyj.2012.10.016

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