Forensic Toxicology最新文献

Purpose: Although helium is commonly used as a carrier gas for gas chromatography/mass spectrometry (GC-MS), this practice is unsustainable owing to the unstable supply and rising prices of helium. Therefore, this study investigated nitrogen as an alternative carrier gas in forensic toxicology applications to suggest a simple transfer of analytical conditions.

Methods: GC-MS using nitrogen was compared with the conventional helium-based method for 34 compounds, including illegal drugs, medications, and pesticides. The targets were analyzed in a 10 µg/mL solution under constant linear velocity and pulsed splitless modes. Three analytical conditions were evaluated by varying the linear velocity and ionization voltage.

Results: With nitrogen as the carrier gas, the average peak height was 10% compared to that with helium. The similarity index of the obtained mass spectra and that acquired with helium averaged at 84. However, under conditions at which the velocity decreased, the peak height was approximately the same, whereas the spectral similarity index increased to an average of 91. Furthermore, under conditions in which the ionization voltage was changed, the spectral similarity index slightly decreased to an average of 81, whereas the peak height significantly increased to an average of 87%.

Conclusions: Although analysis using nitrogen with the same level of detection sensitivity as that used with helium was challenging, qualitative analysis was considered sufficient for samples with high concentrations, such as powders, tablets, liquids, and plants. Thus, nitrogen can serve as a viable alternative carrier gas to helium in GC-MS analysis.

Purpose: Ethylene glycol (EG), a widely used industrial compound, has been implicated in accidental poisoning and homicide. Although the nephrotoxic mechanisms of EG are well characterized, its acute hepatotoxic potential remains underexplored. This study investigated histopathological and molecular alterations in the liver of rats following acute administration of EG. Possible dysfunction of an anti-oxidative pathway involving ferroptosis (glutathione peroxidase 4, Gpx4; solute carrier family 7 member 11, SLC7A11) is also examined.

Methods: Male rats (8-week-old, male) were orally administered EG (8 g/kg) and euthanized at 2 and 5 days post-exposure by an administration of an overdose of anesthetic (40 mg/kg sodium pentobarbital). Serological analysis was performed to assess liver function. Liver tissues were evaluated by histology, transmission electron microscopy, and transcriptome analysis.

Results: Serological findings indicated transient liver damage at 2 days post-exposure, followed by recovery at 5 days. Transmission electron microscopy revealed glycogen accumulation, corroborated by periodic acid-Schiff and periodic acid-methenamine silver staining. Histological analysis revealed an increased number of nucleoli, correlating with upregulation of ribosomal genes on microarray analysis, particularly at 5 days post-exposure. In addition, significant decreases in Gpx4 and SLC7A11 expression were observed in rat livers treated with EG and Huh-7 human hepatoma cells, suggesting reduced cellular antioxidative capacity as a contributing factor to transient liver damage.

Conclusions: These findings reveal a pathway underlying EG-induced transient liver damage and suggest a possible mechanism of recovery, thereby providing new insights into EG poisoning.