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Onterris is a global environmental solutions company partnering with organizations to solve complex challenges where environmental pressures, regulatory expectations and operational risks intersect.
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Prepare for escalating environmental risks with expert solutions designed to perform under pressure.
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Nathan Koonce, PhD

Project Toxicologist

About Dr. Koonce

Dr. Nathan A. Koonce is a Project Toxicologist at Onterris with specialized experience in applied toxicology, regulatory research, and product safety. He has supported both private and public sector clients in areas such as environmental toxicology, risk assessment for complex substances, and development of alternative testing strategies. His work includes contributing to international consensus standards and advising on regulatory approaches for complex generic products. Dr. Koonce has authored over 20 peer-reviewed publications spanning topics such as particulate matter toxicology, radiation exposure, and chemical hazard mitigation. His consulting roles often include litigation support, development of sampling and analysis plans, and interpretation of toxicological data in both environmental and occupational contexts.

As a member of the Onterris Toxicology Emergency Response Program (TERP), Dr. Koonce leads air monitoring and environmental sampling teams during chemical emergencies to support worker and public safety. His combined experience in laboratory science, regulatory frameworks, and field operations equips him to deliver responsive, science-based solutions for clients navigating complex toxicological challenges.


Education

  • Ph.D., Interdisciplinary Biomedical Sciences, University of Arkansas for Medical Sciences, Little Rock, AR
  • M.S., Pathology, University of Arkansas for Medical Sciences, Little Rock, AR
  • B.A., Chemistry, University of Arkansas, Fayetteville, AR

Practice Areas

  • Product Safety
  • Toxicology