About Us

Ascertain Forensics at Redwood Toxicology Laboratory understands that forensic toxicology testing requires a qualified drug testing team. Our team has decades of combined experience in the field of forensic toxicology and over 50 years specifically in postmortem and human performance testing. Ascertain Forensics provides reliable and actionable information through timely results, effective training resources, reasonable prices, and excellence in customer support.

Ascertain Forensics is a leading provider of expert toxicology services. Utilizing thorough analytical test methods for multiple specimen types, our scientists and qualified support team have extensive experience supporting criminal case investigations. Ascertain Forensics can target a wide range of prescription drugs and illicit drugs—with particular expertise detecting new psychoactive substances (including so-called “legal highs” and ”bath salts”).

A Leading Laboratory

Ascertain Forensics at Redwood Toxicology Laboratory is a federally certified laboratory specializing in accurate laboratory-based testing with rapid turnaround time. Located in Santa Rosa, California, Redwood Toxicology Laboratory started as a small business in 1994 and operates today as the largest single-location toxicology laboratory in the United States. We employ more than 250 people, process more than 4.5 million specimens, and sell more than 10 million rapid onsite alcohol and drugs-of-abuse devices each year.

Our laboratory has more than two decades of experience providing drug-testing solutions to more than 15,000 active agencies across the nation.

  • Clients include district attorneys, police, sheriff, correctional, probation/parole, drug courts, DUI courts, mental health facilities, and private treatment agencies.
  • More than 15,000 active agencies across the nation, with more than 2,500 clients in California.
  • 48 counties in California have an active probation/parole account with our laboratory.
  • We hold state-level contracts in more than two dozen states, including two cooperative multi-state contracts for convenient purchasing options.


Forensic testing demands fast and accurate analysis. Find out how we can help you improve efficiencies with accurate detection services.

Contact Us

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3650 Westwind Blvd
Santa Rosa CA, 95403

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