Gary Thomas Harraka
Arlington,VA
Summary
Environmental scientist with a background spanning laboratory toxicity testing, graduate research, and federal ecological risk assessment. Combines ecotoxicology study evaluation, biological data analysis, and regulatory writing with leadership on technical and training teams, peer review, and policy drafting support.
Overview
12
12
years of professional experience
Work History
Biologist
U.S. Environmental Protection Agency
Washington, District of Columbia
05.2021 - Current
- Prepared pesticide ecological risk assessments within the Environmental Fate and Effects Division (EFED) of the Office of Chemical Safety and Pollution Prevention (OCSPP) that met Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), Endangered Species Act (ESA), and Federal Food, Drug, and Cosmetic Act (FFDCA) requirements.
- Led ecological assessment efforts through multiple review cycles in collaboration with public- and private-sector stakeholders.
- Evaluated ecotoxicological studies to determine study suitability for quantitative risk assessment and identify relevant apical endpoints.
- Reviewed ecological risk assessments and agency actions as a secondary reviewer, providing technical support to ensure compliance and accuracy in document submissions.
- Integrated chemists' estimated environmental exposure estimates with EPA-reviewed toxicity data through quantitative and qualitative analysis.
- Built expedited process for evaluating listed species within proposed action areas for FIFRA Section 18 emergency exemption requests targeting especially harmful pests within specific agricultural year and geographic region.
- Contributed to development of new chemical risk assessment template adopted across division to improve clarity, reduce redundant methodology and data tables, and create consistency in published documents.
- Provided technical support for EPA Herbicide Strategy drafting, strengthening EFED ecological risk assessment quality and efficiency through a regulatory framework for evaluating herbicide effects on federally listed species and designated critical habitat. Recognized with EPA Bronze Medal in 2024 as a member of the team.
- Co-led the EFED Training Team from 2023 to present (approximately 50 employees trained), managing annual format, schedule, lecture topics, presenter recruitment, and session moderation.
- Co-chaired Aquatic Biology Technical Team from September 2023 to October 2024, leading weekly scientific discussions on ecotoxicity study review, guest lectures, and training sessions with EPA, Fish and Wildlife Service (FWS), National Marine Fisheries Service (NMFS), and public-sector scientists.
Laboratory Technician II
Enthalpy Analytical
San Diego, CA
10.2019 - 05.2021
- Performed freshwater, marine, and sediment toxicity testing, including whole-effluent toxicity (WET) testing, under U.S. EPA, ASTM International, and California requirements.
- Monitored survival, growth, and reproduction endpoints for sea urchin and daphnia tests to ensure compliance with toxicity testing protocols.
- Maintained freshwater and marine test organisms and in-house cultures, assisted with sample intake and daily test-dilution preparation, and reviewed experimental and water-quality data to support NPDES permit compliance and identify potential toxicity sources.
- Trained new staff on culture maintenance and routine laboratory procedures, ensuring adherence to quality assurance and safety requirements.
Graduate Research Assistant
University of California, Riverside
Riverside, CA
08.2017 - 08.2019
- Completed thesis research that characterized estrogenicity in effluent-dominated Santa Ana River through field sampling, in vitro cell bioassays, and in vivo medaka exposures.
- Conducted aseptic cell culture, fish tissue collection, RNA isolation and purification, PCR/qPCR, and gel electrophoresis to support lab and field studies.
- Advanced toxicology method validation for apical endpoints, including survival, development, growth, and reproduction.
- Collaborated on interdisciplinary toxicology and wastewater-treatment research with graduate, postdoctoral, and faculty researchers; analyzed findings using Excel, GraphPad Prism, and RStudio; trained peers in field and laboratory methods.
- Authored scientific reports, literature reviews, and presentations for state and national meetings, including a platform presentation at 2019 Southern California SETAC meeting in La Jolla.
Environmental Scientist I and Construction Specialist I
CDM Smith
, California and Virginia
07.2014 - 07.2017
- Conducted field surveys, site assessments, and soil-gas and groundwater monitoring to ensure environmental regulatory compliance, applying knowledge of NEPA and CEQA.
- Updated groundwater-quality maps and completed asset surveys using ArcGIS Collector.
- Prepared construction documents and layout drawings, ensuring adherence to environmental compliance standards on-site.
- Reviewed subcontractor proposals for cost and price analysis, coordinated project scope and schedules, and facilitated estimating and materials procurement.
Education
Master of Science - Environmental Science (Ecotoxicology)
University of California, Riverside
Riverside, CA05-2019
Bachelor of Science - Environmental Science and Technology
University of Maryland, College Park
College Park, MD05-2014
Skills
- Ecological risk assessment
- Regulatory compliance
- Ecotoxicology methods
- Toxicity testing
- Laboratory research experience
- Biological data analysis
- Field sampling
- Laboratory QA/QC
- Training management
- Scientific communication
Personal Information
Availability: Open to relocation to San Diego, CA
Selected Publications
- Cochran, K. H., et al., including Harraka, G. (2024). Chlorination of Emerging Contaminants for Application in Potable Wastewater Reuse: Disinfection Byproduct Formation, Estrogen Activity, and Cytotoxicity. Environmental Science & Technology.
- Harraka, G., et al. (2021). Evaluating the estrogenicity of an effluent-dominated river in California, USA: Comparisons of in vitro and in vivo bioassays. Science of the Total Environment.
- Chen, Q., et al., including Harraka, G. (2020). Bioassay guided analysis coupled with non-target chemical screening in polyethylene plastic shopping bag fragments after exposure to simulated gastric juice of fish. Journal of Hazardous Materials.
- Magnuson, J., et al., including Harraka, G. (2020). Metabolic Profiles in the Brains of Juvenile Steelhead (Oncorhynchus mykiss) Following Bifenthrin Treatment. Environmental Science & Technology.
Timeline
Biologist
U.S. Environmental Protection Agency
05.2021 - Current
Laboratory Technician II
Enthalpy Analytical
10.2019 - 05.2021
Graduate Research Assistant
University of California, Riverside
08.2017 - 08.2019
Environmental Scientist I and Construction Specialist I
CDM Smith
07.2014 - 07.2017
Master of Science - Environmental Science (Ecotoxicology)
University of California, Riverside
Bachelor of Science - Environmental Science and Technology
University of Maryland, College Park