Background: Ethylene glycol (EG) is widely used, but it is highly toxic and difficult to diagnose post-mortem due to nonspecific autopsy findings and the absence of EG in routine toxicological screening tests.

Methods: We report two medico-legal cases (suicides) in which toxicological investigations were guided by information relating to the cases, namely the presence of a liquid suspected of containing EG near the bodies. Autopsy findings were nonspecific in Case #1; only an external examination in Case #2. EG was analyzed using a GC-FID method.

Results: In Case #1 (female, 50s), cardiac blood (peripheral blood was not available) contained EG at 196 mg/L and blood levels of fluoxetine (4.94 mg/L), norfluoxetine (3.09 mg/L), and nordiazepam (2.71 mg/L) were supratherapeutic. EG was also determined in vitreous humor , urine, bile, and gastric content. In Case #2 (female, 60s), the concentration of EG in peripheral blood was 558 mg/L and no other toxic substances were detected.

Conclusion: Both cases fall within the range of post-mortem EG concentrations in blood (58-7790 mg/L) reported in cases of fatal poisoning. The cause of death in these 2 cases was attributed to severe metabolic acidosis due to EG, with a contributing factor of co-intoxication with psychotropic drugs in Case #1. These cases confirm that fatal EG poisoning can go undetected without targeted post-mortem toxicological analysis and that specific EG screening tests should be included in post-mortem analytical protocols when the circumstances of a case ( i.e. , the presence of a suspicious liquid or antifreeze-like liquid) raise suspicion.