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Senior Scientists

Education
M.S., Environmental Toxicology, University of Washington
H.B.S., Bioengineering, Oregon State University
Fundamentals of Engineering in Chemical Engineering, 2012
Expertise
- Inhalation Toxicology
- Risk Communication
- Occupational Health
- Product Safety
- Risk Assessment
- Toxicology
Rebecca C. Ticknor, M.S.
Senior Toxicologist
Ms. Ticknor is a senior toxicologist with experience in inhalation toxicology, occupational health, product safety, and human health risk assessment. She provides technical support for toxic tort litigation and conducts safety and risk assessments for various environmental contaminants, medical devices, and consumer products. Before joining Gradient, Ms. Ticknor worked at a consulting firm where she provided technical support for asbestos, talc, and mold litigation and performed human health risk assessments on various compounds including PCBs, solvents, manufacturing leachates, and PM2.5. Ms. Ticknor earned her master’s degree from the University of Washington, where she researched the effects of in utero exposure to diesel exhaust on the development of atherosclerotic plaque and epigenetic alterations.
Education
M.S., Environmental Toxicology, University of Washington
H.B.S., Bioengineering, Oregon State University
Fundamentals of Engineering in Chemical Engineering, 2012
Expertise
- Inhalation Toxicology
- Risk Communication
- Occupational Health
- Product Safety
- Risk Assessment
- Toxicology
Representative Projects
Radiation Risk Assessment: Evaluated risks of potential residential exposure to radionuclide contamination in an adjacent landfill, including a variety of cancer and non-cancer human health endpoints and exposure routes.
Skin Sensitization Risk Assessment: Performed hazard assessments and quantitative risk assessments for skin sensitization and irritation after potential exposure to constituents of various consumer products designed to be in contact with the skin. Developed exposure levels for potential chemicals of concern intended to protect consumers from adverse skin reactions from contact with the products.
Air Pollution Risk Assessment: Evaluated risk of a variety of cardiovascular, respiratory, and cancer endpoints and county-wide exposure to constituents of air pollution.
TCE, PCE, and 1,1,1-TCA Risk Assessment: Evaluated risk of Non-Hodgkin’s lymphoma after potential exposure to TCE, PCE, and 1,1,1-TCA from drinking water and bathing water.
PCB Risk Assessment: Evaluated risk of multiple polychlorinated biphenyls (PCBs) contaminating various waterways throughout the US, focusing on immunotoxicity, carcinogenicity, genotoxicity, and developmental toxicity endpoints.
Product Safety Risk Assessment: Determined allowable concentrations of various metals and chemicals in cloth uniforms and metallic jewelry and accessories to prevent adverse reactions from dermal contact and accidental ingestion.