1,1-Difluoroethane Forensic Aspects for the Toxicologist and Pathologist.

Area of Science:

• Forensic toxicology
• Pharmacology
• Environmental health

Background:

• 1,1-Difluoroethane (DFE) is a common propellant in consumer products.
• DFE abuse as an inhalant presents significant medicolegal challenges.
• Understanding DFE's effects and detection is crucial for investigations.

Purpose of the Study:

• To review the pharmacology of 1,1-Difluoroethane (DFE).
• To address medicolegal questions regarding DFE detection and effects.
• To provide insights into DFE's impact on traffic safety and postmortem analysis.

Main Methods:

• Literature review of DFE pharmacology and toxicology.
• Analysis of case studies involving DFE in impaired driving and postmortem investigations.
• Examination of DFE detection times and concentrations in biological specimens.

Main Results:

• DFE causes rapid CNS depressant effects, with onset in seconds and duration of minutes.
• Impaired driving cases involving DFE frequently include collisions.
• DFE is detectable in blood up to 3 hours post-incident, but concentrations dissipate rapidly.
• Passive exposure unlikely to yield detectable blood/urine concentrations (>2.6 µg/mL).
• DFE concentrations in postmortem and impaired driving cases vary widely (0.14–460 µg/mL and 0.16–140 µg/mL, respectively).

Conclusions:

• DFE's rapid onset and short duration of effects complicate real-time impairment assessment.
• Accurate detection and interpretation of DFE concentrations are vital for medicolegal and traffic safety investigations.
• Alternative specimens like lung or tracheal air may be necessary for postmortem DFE analysis.