Jason E. Johnston

Mr. Johnston has 19 years of experience in the areas of exposure and risk assessment. He has conducted multiple exposure assessments in residential, occupational, hazardous waste sites, and consumer product settings for the U.S., Canada, EU, and South America using a variety of computer tools. Mr. Johnston manages and conducts dietary and non-dietary residential and occupational exposure assessments of pesticides, particularly those mandated by the EPA Food Quality Protection Act of 1996. He has extensive experience in using and interpreting the Pesticide Handler Exposure Database and European exposure databases. Mr. Johnston has also worked with industry task forces in developing a pesticide occupational exposure database and a regulatory screening model to estimate exposures to antimicrobial agents used in the home.

Mr. Johnston has also provided advice on scientific and regulatory matters related to environmental, occupational, and consumer exposure- and risk-related issues. He has assisted with the development of strategies for exposure mitigation using engineering controls, protective clothing, and improvement of label language pertaining to user safety. Additionally, he has managed and conducted assessments of dietary and non-dietary exposure to pesticides and other chemicals in support of registration, re-registration, and special review activities. Mr. Johnston has also performed scientific analyses of chemical storage, handling, and recycling processes; occupational health testing; and exposure modeling. He has analyzed environmental risk management policies and proposed federal regulations in an advocacy context.

Petersen BJ, Petersen SR, Barraj L, Johnston JE. Using two-day food consumption survey data for longitudinal dietary exposure analyses. In: Assessing Exposures and Reducing Risks to People from the Use of Pesticides. Seiber JN, Krieger RI, Ragsdale N (eds), Oxford University Press, 2007.

Pirages SW, Johnston JE. Municipal waste combustion and new source performance standards: Use of scientific and technical information. In: Keeping Pace with Science and Engineering: Case Studies in Environmental Regulation. National Academy Press, Washington, DC, 1993.

Presentations

Johnston JE, Smith K, Wang C, Petersen B, McCormick W, Shah H. A new model to assess incidental ingestion exposures to residential countertop cleaning products. Presented at the International Society of Exposure Analysis/International Society for Environmental Epidemiology Annual Conference, Paris, France, 2006.

Johnston, JE, Petersen B, Petersen S. A data-matching algorithm to generate longitudinal dietary consumption pattern profiles. Presented at the International Society of Exposure Analysis Annual Conference, Philadelphia, PA, 2004.

Johnston JE, Merricks DL. Improvement in worker exposure and risk assessment using biomarkers: A case study. Presented at the Society for Risk Analysis Annual Meeting, New Orleans, LA, 2002.

Johnston JE, Walls CL, Petersen B. Calendex^TM: A calendar-based model to assess aggregate exposure. Presented at the International Society of Exposure Analysis Annual Conference, Charleston, SC, 2001.

Johnston JE, Walls CL. Calendex^TM overview and results of aggregate assessments. Presented at the Scientist-to-Scientist Model Comparison Meeting of Residential Aggregate Human Exposure Models sponsored by the USEPA Environmental Research Center, Research Triangle Park, NC, 2001.

Johnston JE, Hentz K. Advanced topics in risk assessment. Day-long continuing education seminar presented at the Professional Conference on Industrial Hygiene sponsored by the American Academy of Industrial Hygiene, 1997 and 1998.

Johnston JE, Pirages SW. Policy implications of risk assessment in soil remediation programs. Presented at Superfund ’92, Washington, DC, 1992.

Pirages SW, Johnston JE, Aylward L. Risk assessment: It’s not really black magic. Presented at WasteTech ’91, Toronto, Canada, 1991.

Prepared comments on a draft EPA exposure and risk assessment for residential and occupational uses of a pesticide undergoing re-registration review. Based on the submitted comments, EPA made significant changes in the revised assessment, resulting in improved characterization of pesticide use patterns, exposures, and risks.

Developed protocols for studies of occupational and residential exposures to pesticides. In one case, the study included the use of biomarkers, and risk assessments were prepared for submission to EPA and other national regulatory authorities using the biomonitoring data.

Developed a survey instrument to obtain information on pesticide uses by growers and incorporated results from the grower survey in refining exposure and risk calculations.

Developed a survey instrument to obtain information related to manufacturing levels and practices for high production volume chemicals and compiled data in support of an industry task force effort to prepare summary documents under the EPA and OECD high production volume chemical programs.

Conducted several assessments of occupational and residential application and post-application exposures to pesticides in support of registration and re-registration activities in the U.S.

Conducted several exposure assessments for pesticide operators, workers, and bystanders in support of European Union registrations.

Created an aggregate exposure assessment using hypothetical data for multiple residential uses of a pesticide (crack and crevice, lawn, and garden applications) with proprietary software (CalendexTM).

Conducted exposure assessments for a variety of consumer products under California Proposition 65 regulations.

Designed strategy for an investigative study of using publicly available U.S. Census information to generate a statistical description of the distances between chemical plants, paper manufacturing facilities, and oil refineries and the nearest resident.

• International Society of Exposure Analysis
• Society for Risk Analysis