Mephedrone detected in hair can add exposure history to a death investigation, but it does not replace the acute blood result. A study reporting four forensic examples included three deaths and one living complainant. Different hair lengths and blood collection sites prevented the results from serving as a simple concentration-to-dose or concentration-to-impairment scale.
The study combined submitted samples and forensic examples
Kintz described 112 submitted hair specimens, mostly from the United Kingdom, tested in clinical or forensic investigations of stimulant exposure. Twenty-four contained mephedrone. This was a selected testing population rather than a representative prevalence survey.
The paper separately described four forensic investigations: a suspected fatal intoxication, an alleged sexual assault, a fatal crash and a drowning. The alleged-assault complainant was alive and had hair collected three weeks after the reported event. That example must not be counted as a fourth autopsy.
How the hair was measured
Hair was washed twice with methylene chloride, dried, cut and extracted before derivatization and GC–MS analysis. The method used MDMA-d5 as the mephedrone internal standard. Its reported linear range was 0.1–50 ng/mg, detection limit 20 pg/mg, and within-batch precision 17.6% at 1 ng/mg.
A detection limit is not an administered-dose threshold. The paper acknowledged the absence of controlled dose-to-hair data and the limited knowledge of each person’s consumption frequency. Washing was part of the procedure, but did not constitute a controlled demonstration excluding every contamination scenario.
Three fatal cases had different matrices and lengths
In the first case, a 28-year-old man had mephedrone at 5,432 ng/mL in cardiac blood and 6.99 ng/mg in a whole 4 cm hair sample. Cocaine and metabolites were also detected. A body examination was performed, but the prosecutor did not request an autopsy, limiting the pathological investigation described.
The crash case involved a 31-year-old man with cardiac-blood mephedrone at 103 ng/mL and ethanol at 0.41 g/L. His whole 3 cm hair sample contained mephedrone at 0.38 ng/mg and MDMA at 2.06 ng/mg.
The drowning case involved an 18-year-old man with femoral-blood mephedrone at 88 ng/mL, urine at 2,430 ng/mL and bile at 71 ng/mL. Blood ethanol was 1.06 g/L. A whole 6 cm hair sample contained mephedrone at 1.21 ng/mg, alongside MDMA and cocaine.
Why the hair numbers cannot rank the final exposure
These whole-length hair results integrated different lengths of material. They were not identically timed segments, and the paper lacked controlled dosing histories. A longer sample could encompass a different exposure period; it did not automatically document a higher final dose.
Co-detection in hair also did not establish that every drug was consumed simultaneously or contributed to the fatal event. The blood findings addressed a different specimen and time context, with cardiac blood in two deaths and femoral blood in the third.
Interpretive opinions were not experimental impairment measurements
The author considered some blood findings potentially fatal or indicative of impairment. The reported examples did not directly measure pre-event performance or establish a validated mephedrone impairment cutoff. Hair concentrations supplied no independent proof of crash causation, drowning mechanism or fatal toxicity.
Use hair as additional history while preserving collection site, segment length, units and missing timing evidence. For a related limitation, see postmortem hair markers and contamination interpretation.
Primary source
Kintz P. Evidence of 2 Populations of Mephedrone Abusers by Hair Testing. Application to 4 Forensic Expertises. Current Neuropharmacology. 2017;15:658–662. doi:10.2174/1570159X14666161026152107.
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