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Presenter Biosketches

Cumulative Risk Assessment Webinar Series

Krista Christensen Krista Christensen
National Center for Environmental Assessment
U.S. Environmental Protection Agency

Krista joined the National Center for Environmental Assessment (Washington division) in August of 2010, after completing her MPH and PhD in epidemiology at Emory University, and post-doc at the Universite de Montreal. Her research background is in environmental chemical exposure and impact on child health and pubertal development. As an epidemiologist in the Quantitative Risk Methods Group of NCEA, Krista works on the IRIS chemical assessments for Libby amphibole asbestos, phthalates, PCBs and beryllium. She also works on methods development for risk assessment.

Krista Ellickson, Ph.D. Krista Ellickson, Ph.D.
Risk Assessment
Minnesota Pollution Control Agency

Dr. Ellickson joined the Minnesota Pollution Control Agency in 2007 after completing her Ph.D. at Rutgers University and postdoctoral work at both Rutgers and the University of Wisconsin-Madison. Her work at the Agency includes the incorporation of cumulative risk assessment principles into regulatory risk assessments in Minnesota and, more specifically, the implementation of a unique Minnesota statute requiring such assessments. This statute originated from an environmental justice movement in South Minneapolis. It requires the agency to “analyze and consider the cumulative levels and effects of past and current environmental pollution from all sources on the environment and residents” before an air permit may be issued. Dr. Ellickson also is involved in the implementation of the Agency’s environmental equity policy, the review of human health risk assessments for facilities, and an information-gathering team for the emerging issues related to frac sand mining in Minnesota. She currently is the lead on an EPA community-scale air toxics grant targeting passive and active air sampling for Polycyclic Aromatic Hydrocarbons in an urban environment. She has drawn upon the risk communication experiences she gained in implementing the cumulative statute to incorporate community involvement and expanded outreach into the community air toxics study.

Neal Fann Neal Fann
Environmental Protection Specialist
Office of Air and Radiation
U.S. Environmental Protection Agency

After graduating from the Stanford School of Public Policy in 2003, Mr. Fann began work in the Office of Air and Radiation of the U.S. Environmental Protection Agency as a Presidential Management Fellow, where he now characterizes the human health impacts, and monetized benefits, of changes in air pollution. Mr. Fann manages the environmental Benefits Mapping and Analysis Program (BenMAP), the PC-based program that the EPA uses to estimate the health and economic benefits of air quality rules. His research interests include characterizing the magnitude, distribution and sources of air pollution risk across multiple pollutants and emission sectors.

Mr. Fann’s current work uses source apportionment photochemical modeling to apportion by emission sector the health burden of current and projected fine particulate matter (PM2.5) and ozone levels. He recently authored articles examining the current public health burden of fine particulate matter and ground-level ozone in the United States and a proof-of-concept approach for maximizing the public health benefits of air quality improvements while achieving a more equitable distribution of risk.

Ari S. Lewis Ari S. Lewis, M.S.
Environmental Health Principal Scientist and Toxicology Team Manager at Gradient – Environmental Consulting

Ms. Lewis is a Principal Scientist and Manager of the toxicology team at Gradient, an environmental consulting firm in Cambridge, Massachusetts. Her expertise in toxicology and risk assessment allows her to lead and contribute to a variety of projects, including product safety evaluations, regulatory comment, green chemistry assessments and cumulative risk assessment research. She also has particular expertise in metals risk assessment. In this capacity, Ms. Lewis has both published and presented extensively on the carcinogenic risks of arsenic and provided direct input to the U.S. Environmental Protection Agency (EPA) on arsenic regulatory issues. She has provided congressional testimony on the appropriate use of risk assessment in pending regulations regarding coal ash disposal. Ms. Lewis has expertise in developing quantitative human health risk criteria for chemicals with limited toxicity data. Before joining Gradient, Ms. Lewis earned her M.S. degree at Cornell University; her thesis project investigated the molecular and cellular responses to arsenic exposure during early animal development.

Practice Areas and Expertise:

  • Toxicology
  • Human Health Risk Assessment
  • Cumulative Risk Assessment

M.S., Environmental Toxicology, Cornell University
B.A., Biology/Environmental Sciences, University of Pennsylvania

Jonathan London Jonathan London
Assistant Professor and Director
Center for Regional Change
University of California, Davis

Jonathan London is an educator, researcher, and community-builder with expertise in participatory research, rural community development, and community engaged planning. He is Assistant Professor in the UC Davis Department of Human Ecology.

Jonathan’s research addresses conflicts and collaboration in natural resource and environmental issues, with a particular emphasis on marginalized rural communities and environmental justice issues in the Sierra Nevada and the Central Valley. He is the lead researcher on the development of several cumulative impacts/ environmental justice analyses in California. Jonathan is committed to a participatory and collaborative research approach, actively engaging communities in the production of application of knowledge to improve social, economic, political, and environmental conditions.

Jonathan directs the UC Davis Center for Regional Change, which serves as a catalyst for multi-disciplinary research to inform strategies to build healthy, prosperous, equitable, and sustainable regions.

Jonathan holds a BA in Environmental Studies from Brown University, and a Masters in City and Regional Planning and a Ph.D. in Environmental Science Policy and Management from UC Berkeley. Prior to coming to UC Davis, he co-founded and directed Youth In Focus, a pioneering non-profit organization, dedicated to youth empowerment and social change through youth-led research, evaluation and planning throughout the California.

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