Select Page

John R. Griffin

John R. Griffin
Senior Consultant

John R. Griffin

Senior Consultant

Mr. John Griffin has more than 20 years of experience in the areas of exposure assessment, risk assessment, risk communication, air emissions modeling, fate and transport modeling, database development, litigation support, and geographic information systems (GIS). He is a highly detail-oriented scientist who has led and participated in interdisciplinary teams to solve complex problems for his clients using the best science available. Currently, he performs risk assessments associated with consumer, occupational, and environmental exposure to a variety of chemicals including asbestos, per- and polyfluoroalkyl substances (PFAS), petroleum compounds, dioxins, PCBs, PAHs, and chlorinated solv...

Mr. John Griffin has more than 20 years of experience in the areas of exposure assessment, risk assessment, risk communication, air emissions modeling, fate and transport modeling, database development, litigation support, and geographic information systems (GIS). He is a highly detail-oriented scientist who has led and participated in interdisciplinary teams to solve complex problems for his clients using the best science available. Currently, he performs risk assessments associated with consumer, occupational, and environmental exposure to a variety of chemicals including asbestos, per- and polyfluoroalkyl substances (PFAS), petroleum compounds, dioxins, PCBs, PAHs, and chlorinated solvents. He uses GIS-based site risk assessments to guide remedy and cleanup decisions and has conducted GIS-based region-wide population risk assessments to evaluate the long-range transport of chemicals in the environment. He has particular expertise in creating, managing, and analyzing large environmental sampling data sets. In addition, Mr. Griffin has developed and conducted exposure and risk assessments for various air emissions sources such as diesel engines, ceramic product kilns, coal-fired power plants, and coke oven batteries. He has evaluated exposure and risks from vapor intrusion at residential, commercial, and industrial properties.

Read More    Read Less   

Human Health Risk Characterization of PFAS Chemicals at a Superfund Site

Case Study

January 20 2023

Risk Assessment

Former Creosote Wood Treatment Facility Navassa Superfund Site, North Carolina Prepared a human health risk assessment in collaboration with EPA and the North Carolina Department of Environmental Quality. The evaluation focused on exposure to site soils by residential, commercial, and recreational receptors. Chemicals of potential concern (COPCs) for the site included dioxins and furans, PAHs, and pentachlorophenol.
Groundwater Exposure at a Former Solvent and Waste Reprocessing Facility Superfund Site, New Jersey Conducted a baseline human health risk assessment to assess potential risks to human health from hypothetical future use of groundwater by offsite residential receptors. Key COPCs included vinyl chloride, trichloroethylene, and PFAS.  Pathways evaluated included ingestion as a drinking water source and dermal and inhalation exposure during showering.
Groundwater Evaluation for Nonpotable Purposes at an Electrical Parts Manufacturing Facility, Ohio Evaluated exposure to 1,4-dioxane in groundwater by offsite residential receptors assuming groundwater use for nonpotable activities. Of the potential exposure routes, exposure through the ingestion of homegrown produce irrigated with well water posed the greatest potential risk. Calculated a health protective concentration for 1,4-dioxane in well water using EPA methods. The concentrations measured in groundwater were compared to site‑specific risk-based screening levels, and the analysis demonstrated that groundwater was safe for all nonpotable uses.
Risk Assessment to Support Litigation Involving PFAS Exposure, Michigan Evaluated PFAS exposures and potential risks from drinking water at multiple industrial waste disposal sites.  The litigation support work included development of a database of plaintiffs and potential exposures based on location and residence time.  Biomonitoring data was analyzed in the context of existing toxicology data.
PFAS Risk Assessment and Drinking Water Regulation, Nationwide Evaluated physiologically based pharmacokinetic modeling and benchmark dose models to determine the appropriate estimation of risk associated with emerging PFAS compounds such as GenX.  Performed review and analysis of the toxicological and exposure assumptions used in the development of drinking water guidelines from multiple federal agencies and states.
Risk Assessment of Agricultural Burning, Southeast Analyzed the potential exposure and risks associated with agricultural burning to support litigation.  The work involved reviewing emissions estimates, air modeling data, and air monitoring data for particulate matter and various air toxics.  Used GIS to examine the spatial distribution of historical burns to determine appropriate placement of monitoring locations.
Deepwater Horizon, Gulf of Mexico Evaluated potential exposure and risks to workers and nearby residents from the Deepwater Horizon oil spill.  Assisted in the development of sampling needed for the assessment of potential exposures.  Identified, assembled, analyzed, and mapped the sampling data generated by multiple agencies and stakeholders to fully understand the potential exposure and risks.  Generated a mapping database to track all dispersant applications during the spill response.  Provided scientific expertise to the legal team that created the Deepwater Horizon Oil Spill Medical Benefits Settlement.
Risk Assessment of DDT Dust Contamination, Alabama Provided litigation support and technical analysis involving exposure to DDT in indoor dust.  The focus was on potential historical exposures and the impacts of past exposure on property values.  The EPA World Trade Center dust screening value approach was utilized to demonstrate the de minimis future risks associated with current levels of DDT.
Risk Assessment of Arsenic in Poultry Litter, Arkansas Provided litigation support and technical review related to the use of roxarsone in poultry production.  The main area of concern was exposure to arsenic in air and house dust from the spreading of poultry litter.  Potential exposures and risks from contaminated dust in homes were evaluated and put into context of background levels of arsenic in dust and air.
Risk Assessment of Hexavalent Chromium, Multiple Locations Assessed the potential risks associated with community exposure to a former industrial site contaminated with chromium ore processing residue.  Evaluated the risk reduction capability of a proposed remedy for the site.  Also evaluated chromium worker exposures and potential risks for an industrial client.
Risk Assessment of Drinking Water Contaminants, Multiple Locations Estimated potential risks from multiple drinking water contaminants including MTBE, PFAS, arsenic, and others to support litigation.  Evaluations included assessment of local impacts and evaluation of spatial and temporal trends in drinking water systems across the United States.
Risk Assessment and Litigation Support for MGP Site Contamination, Illinois Estimated potential risks from presence of PAHs in drinking water distribution pipes for utility companies in support of litigation.  Evaluated potential sources of the contaminants including releases from a former manufactured gas plant (MGP) site and from coal-tar coatings used in the water distribution system.
Risk Assessment of Drywall Off-gassing, Nationwide Developed a sampling program and performed an exposure assessment to evaluate the potential health risks associated with off-gassing from drywall for litigation involving a large home improvement retailer.  Also evaluated potential remediation strategies and health claims.
Risk Assessment of Malathion Spraying, Florida and New York Developed revised exposure estimates from the spraying of malathion in a medfly eradication program in Florida.  Also evaluated ecological impacts from the spraying of malathion in New York City to control mosquitoes.
PCB Contamination from Paper Industry, Michigan and Wisconsin Evaluated the history of the paper industry and the knowledge of PCB contamination and risks to determine the share of liability for the Kalamazoo River and Fox River Superfund sites.
Health Risk Assessment for Aerospace Manufacturing Site, Maryland Developed a site-specific human health risk assessment for an industrial site as part of Maryland’s Voluntary Cleanup Program.  This assessment included the evaluation of soil, groundwater, sediment, and surface water exposures for a variety of receptor populations.  The goal of the assessment was to aid in the development of the cleanup remedies necessary for the redevelopment of the site.
Superfund Site Liability, New England Aided PRPs at a Superfund site in determining their share of the anticipated cleanup costs.  Reviewed historical documents, aerial photographs, spatial distribution of contaminants, and process chemistry to estimate the anticipated cleanup costs and the client’s potential responsibility. Dioxins and PCBs in sediment were the major contaminants of concern.
Superfund and Contaminated Site Work, Multiple Locations Provided database and GIS mapping support for a variety of litigation cases associated with Superfund and contaminated industrial sites.  This support has included evaluation of the adequacy of the data, the spatial distribution of impacts, and the appropriateness of proposed remedies.  Site-specific exposure parameters were often utilized in conjunction with standard exposure parameters to estimate central tendency and reasonable maximum estimates of risks.
Asbestos Risk Assessment, Libby, Montana Evaluated and revised asbestos risk assessments performed by EPA for the Libby, Montana, area as part of cost recovery litigation involving a former vermiculite mine.  Identified multiple inconsistencies in EPA risk calculations that were revised based upon further analysis.  Used GIS to identify distribution of contamination from the mining operations and naturally occurring asbestos contamination.  Provided litigation support for criminal case involving claims that the company had knowledge of the dangers of the potential releases of asbestos from mine operations.
Asbestos Risk Modeling, Nationwide Created a life table analysis model that used cohort-specific mortality data to predict the rates of mesothelioma and lung cancer in a cohort of asbestos exposed workers.  This analysis included the evaluation of the Hodgson and Darnton, Berman and Crump, and Nicholson methodologies.
Activity Based Sampling, Colorado Developed an activity-based sampling program in support of litigation to estimate risks to farmers who were potentially impacted by asbestos-containing insulation that was improperly disposed of during the removal of a former pipeline.  The activities included various tilling and planting activities as well as the evaluation of children playing in contaminated soil.
Risk Assessment and Litigation Support for Coal-fired Power Plants, Southeastern U.S. Evaluated future health impacts on a neighboring state associated with emissions from one of the largest producers of electricity in the United States using GIS, air modeling, and risk assessment methodologies.  PM2.5, ozone, and other criteria pollutants were evaluated in relation to the National Ambient Air Quality Standards.  The analysis also included evaluation of the potential impacts based on future emissions reductions. In addition, the epidemiological and toxicological literature underlying the standards was reviewed to develop estimates of health impacts.

Vapor Intrusion

Vapor Intrusion and Cleanup at Petroleum Site, California Provided litigation support and evaluated vapor intrusion risks and groundwater impacts associated with a petroleum release at a large fuel storage facility for a large energy infrastructure company.  Both soil vapor and groundwater concentrations were analyzed and used to predict indoor air concentrations across a large site.
Vapor Intrusion from Solvents, Arizona Developed an indoor air risk assessment of a former industrial site at the request of the Arizona Department of the Environment.  The assessment utilized vapor intrusion modeling and measurement data to evaluate the risks to current and future users of the site.  This included the use of EPA’s Supplemental Guidance for Assessing Susceptibility from Early-Life Exposure to Carcinogens.
World Trade Center Dust Risk Assessment, Manhattan, New York Provided litigation support and technical analysis of worker exposure to World Trade Center-related contamination in lower Manhattan.  Exposures involved airborne dust containing asbestos, silica, metals, and other toxic compounds.  The work involved reviewing, cataloguing, mapping, and analyzing thousands of pages of data related to potential exposures in dozens of buildings.

Fate and Transport

PERFUM Model Development Supported the development of the Probabilistic Exposure and Risk Model for FUMigants (PERFUM), which was designed to estimate the potential for by-stander risks during the application of soil fumigants.  The model was subject to an EPA Scientific Advisory Board review, and EPA is currently using the model in soil fumigant risk assessments.  Air emission estimates from various field application techniques were developed using field studies to test and validate the model.
Coke Oven Emissions Model, Nationwide Conducted air emissions modeling of coke ovens on behalf of EPA to evaluate the accuracy of the combined use of the Buoyant Line and Source Point model and the Industrial Source Complex model in estimating the dispersion of emissions from multiple facilities throughout the United States.
Biodiesel Fuel Population Health Benefits, Nationwide Evaluated potential health impacts and risk reduction factors for the U.S. population associated with the use of various formulations of biodiesel fuel in heavy-duty diesel vehicles.  The impact of the implementation of various diesel regulations was factored into the evaluation of long-term benefits of the emissions reduction associated with biodiesel fuels.
Triclosan Environmental Impact Assessment, Nationwide Developed a quantitative model to estimate the impact of triclosan on lotic systems following discharge from wastewater treatment plants in the United States.  Developed quantitative estimates of the ecological risk associated with farm application of biosolids containing triclosan.
Coal Ash Storage, Mid-Atlantic Evaluated the potential risks associated with coal ash landfills and storage ponds at eight facilities for a large utility company.  The analysis utilized the groundwater monitoring data collected for compliance with the Coal Combustion Residuals rule.  Evaluated monitoring data, fate and transport, and spatial distribution of the contaminants.
Power Plant Long Range Impacts, Northeastern U.S. Using GIS, air modeling data (Community Multi-scale Air Quality Model), and risk assessment methodologies, developed a population-level risk assessment that examined the health impacts of a midwestern power plant’s emissions on the population of the northeastern U.S.

Product Liability

Talc Consumer Products, Nationwide Provided litigation support and technical analysis involving consumer exposure to talc products with potential asbestos contamination, including body powders and auto body fillers.  Designed and completed exposure simulation studies as well as the risk assessment of these potential exposures.
Asbestos Bankruptcies, Nationwide Provided consulting support and analysis for several bankruptcies associated with asbestos liabilities.  The work involved exposure assessment, risk assessment, and review of claimant medical and occupational histories.  Conducted an evaluation of the epidemiology and regulatory history of asbestos.  Developed and provided oversight for a systematic review and analysis of the medical and exposure information for thousands of claimants.  The review process included the establishment of written guidelines, implementation of a rigorous quality control process involving training sessions for reviewers, and oversight by a team of senior staff who provided guidance throughout the entire review.
Agrochemical and Industrial Chemical Registrations, Nationwide Participated in the review of Reregistration Eligibility Documents for various agrochemicals on behalf of the agrochemical industry.  In addition, provided research and analysis support for the registration of new pesticides regulated under the Federal Insecticide Fungicide and Rodenticide Act.  Prepared and submitted premanufacture notices for new chemical substances in compliance with the Toxic Substances Control Act on behalf of chemical manufacturing clients.  The products registered have included glass coatings, paint additives, and friction product additives.
Diesel Emissions Proposition 65, California Performed a risk assessment under California’s Proposition 65, to determine potential risk to children associated with diesel emissions from school buses.  The analysis included consideration of the potential risks from other forms of transportation if people chose not to ride the bus.
Food Supply Contamination, Nationwide Evaluated the potential liability to a corn flour producer associated with the discovery of Starlink corn (genetically modified) in its inventory.  The analysis was used to support the producer’s insurance claim for removing all yellow corn products from the marketplace for a year.

Air Quality Modeling

NATA and NEI Analysis, Nationwide Analyzed underlying data, calculations, and results of the National Scale Air Toxics Assessment (NATA) for a variety of industry groups.  This assessment also included the evaluation and preparation of comments and corrections for the National Emissions Inventory (NEI) on behalf of individual corporations and industry groups.  Specifically, ethylene oxide and acrylonitrile emissions have been analyzed in detail.
Air Toxics Risks, Multiple Locations Calculated potentials risks associated with soybean processing facilities, tile manufacturers, and others for permitting and compliance with National Emission Standards for Hazardous Air Pollutants using air modeling, air monitoring, and risk assessment approaches.  Reviewed and provided comments and corrections to EPA’s risk and technology reviews for multiple source categories.
RETURN TO OUR TEAM PAGE