Forense LLC
Toxicology Expert Witness Credentials — Rudolph Johnson, PhD
Expert Witness Credentials
The qualifications, positions, and scientific record behind every opinion Dr. Johnson offers in federal and state court.
Areas of Expertise
Litigation-ready expertise across six domains
Toxic Tort & Chemical Exposure
PFAS, heavy metals, VOCs, pesticides, industrial solvents, and other hazardous substances. Causation analysis, dose-response, and exposure pathway reconstruction.
Forensic Toxicology & Lab Standards
Chain-of-custody review, laboratory method validation, anomalous results, drug and alcohol testing disputes, and quality-assurance failures.
Environmental Toxicology
Contaminated site exposure, regulatory threshold analysis, and community health impact assessment.
Military & Occupational Exposure
Burn pit combustion products, Agent Orange, and occupational chemical exposure.
Analytical Chemistry & Mass Spectrometry
Method development and validation, instrument qualification, GC-MS/LC-MS interpretation, and detection limit disputes.
Clinical & Pharmaceutical Toxicology
Drug metabolism, pharmacokinetics, clinical biomarkers, adverse drug reactions, and pharmaceutical toxicity in litigation.
Professional Positions
Current & recent roles
UW School of Medicine & Public Health
Leads Wisconsin's primary public-health laboratory, overseeing analytical testing programs in clinical chemistry, environmental monitoring, and toxicology.
University of Wisconsin–Madison
Academic appointment providing instruction and research in laboratory medicine and toxicology.
U.S. Department of Veterans Affairs
Led VA research into toxic exposures affecting veterans, including burn pit combustion products, PFAS, and other hazardous substance exposures.
CDC, Division of Laboratory Sciences
Directed CDC's chemical emergency laboratory response program, including analytical method development for chemical terrorism agents and drugs of abuse.
Tulane University School of Professional Advancement
Provides strategic guidance on professional science and public-health education programs.
Education
Academic foundation
Purdue University
Dissertation on real-time chemical detection via membrane introduction mass spectrometry, under Dr. R. Graham Cooks — a foundational technology for modern chemical agent identification.
University of Florida, College of Pharmacy
Concentration in clinical toxicology, covering drug metabolism, pharmacokinetics, clinical biomarkers, and pharmaceutical toxicity.
Virginia Military Institute
Undergraduate training in laboratory science and instrumentation automation, providing the technical foundation for advanced graduate study.
Professional Memberships & Editorial
Peer recognition & editorial service
Journal of Analytical Toxicology
Society of Toxicology
Society of Forensic Toxicology
OPCW — Chemical Weapons Convention, The Hague
Publications
90+ peer-reviewed publications
Dr. Johnson's publication record spans analytical chemistry, public-health toxicology, chemical detection, and emergency laboratory preparedness. The full list is available for download.
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