ABT Forensic Toxicology 3

Question 1

Fentanyl analogs such as carfentanil are classified as Schedule I substances and are most commonly detected in forensic cases involving:

Accepted Answer

Opioid overdose deaths with no prescribed opioid use

Answer

Illicitly manufactured fentanyl and its analogs (including carfentanil) are frequently found in counterfeit pills or adulterated heroin and are a leading cause of opioid overdose deaths.

Question 2

Which principle explains why oral fluid (saliva) drug testing reflects recent drug use more accurately than urine?

Accepted Answer

Oral fluid primarily contains parent drug reflecting recent blood levels

Answer

Oral fluid primarily contains the parent drug in equilibrium with plasma, reflecting recent drug use (hours), whereas urine contains metabolites with a longer but more delayed detection window.

Question 3

A critical difference between therapeutic drug monitoring (TDM) and forensic toxicology is that forensic toxicology:

Accepted Answer

Must maintain legally defensible chain of custody and documentation

Answer

Forensic toxicology requires rigorous chain of custody, documentation, and legal defensibility of results because findings may be used as evidence in criminal, civil, or regulatory proceedings.

Question 4

Which compound is measured in blood as a biomarker for chronic heavy alcohol use and has a detection window of approximately 2–4 weeks?

Accepted Answer

Phosphatidylethanol (PEth)

Answer

Phosphatidylethanol (PEth) is a direct ethanol metabolite formed in red blood cell membranes that provides a 2–4 week window for detecting heavy alcohol consumption with high specificity.

Question 5

In forensic death investigations, which toxicological finding is most useful for estimating postmortem interval (PMI)?

Accepted Answer

Vitreous potassium levels

Answer

Vitreous potassium levels rise predictably after death due to cell lysis, and regression equations using vitreous potassium can estimate time since death.

ABT - American Board of Toxicology Practice Test

ABT - American Board of Toxicology Practice Test

ABT Forensic Toxicology 3