Testing for 2,4-dinitrophenol in human hair by LC-MS/MS and interpretation issues

Area of Science:

• Forensic Toxicology
• Analytical Chemistry

Background:

• 2,4-Dinitrophenol (2,4-DNP) is an industrial chemical misused for weight loss and by bodybuilders, leading to numerous fatalities.
• Detection of 2,4-DNP in biological matrices is crucial for forensic investigations.
• Hair analysis for 2,4-DNP has not been previously reported.

Purpose of the Study:

• To develop and validate an original method for detecting 2,4-DNP in human hair.
• To establish the presence and distribution of 2,4-DNP in hair samples from a fatal poisoning case.

Main Methods:

• Methanolic extraction of 2,4-DNP from hair samples.
• Quantification using Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS).
• Method validation including limit of detection (0.01 ng/mg) and linearity (0.1-50 ng/mg).

Main Results:

• The developed LC-MS/MS method successfully detected 2,4-DNP in the hair of a deceased individual.
• Concentrations of 5.15, 13.06, and 25.48 ng/mg were found in different hair segments.
• A regular increase in 2,4-DNP concentration from root to tip was observed, suggesting potential sweat contamination.

Conclusions:

• The study presents a validated method for 2,4-DNP hair analysis, filling a gap in forensic toxicology.
• The findings demonstrate the utility of hair analysis for detecting 2,4-DNP exposure.
• Interpreting hair 2,4-DNP levels requires consideration of external factors like sweat contamination.