Toxicology
Forensic Scientists working in the Toxicology Unit perform blood volatiles analyses, blood drug screening and confirmations, and support the preliminary breath alcohol testing, as well as the Drug Recognition Expert programs.
Toxicology Unit members also assist officers during alcohol workshops. Various analytical techniques are used to determine the presence of drugs in blood and urine samples. Members of this unit often provide expert witness testimony regarding DUI and other cases.
Services Provided
Blood Volatiles - "What was the blood alcohol concentration?” This analysis may also show the presence of propellants (enables spray cans to work) and nitrous oxide. This analysis is performed using Headspace Gas Chromatography with Flame Ionization Detector (GC/FID) and Mass Spectrometry Detection (GC/FID/MS).
Blood Drug Screening - “Is the blood specimen presumptively positive for a drug group?” This analysis is performed using an Enzyme-Linked Immunosorbent Assay (ELISA) and narrows the search of drugs in the blood specimens. The results of this screen determine which drug confirmations are performed.
Blood Drug Confirmations - “What drugs are present in the blood specimen?” This analysis is performed using Gas Chromatography Triple Quadrupole Mass Spectrometry (GC/MS/MS/MS) or Liquid Chromatography Triple Quadrupole Mass Spectrometry (LC/MS/MS/MS). Specific drugs present in the specimen are identified and sometimes quantified in blood drug confirmations.
Drug Recognition Expert (DRE) Program
The Drug Recognition Expert (DRE) evaluates individuals suspected to be under the influence of drugs, including alcohol. After examining the subject based on twelve standardized steps, the DRE can reach a reasonably accurate conclusion concerning the category or categories of drug(s), or medical condition(s), causing the impairment observed in the subject. The evaluation includes tasks such as checking the subject’s blood pressure, body temperature, and pulse rate. The Toxicology Unit supports the DREs by completing the twelfth step in the process, which can verify the DRE’s opinion.