High-performance liquid chromatography study on effects of permanent wave, dye and decolorant treatments on methamphetamine and amphetamine in hair

A multivariable analysis delineating hair color, hair dyeing, and hat wearing as predictors of level of cocaine and MDMA detection in human hair samples

“…With respect to hair dyeing, unlike some other studies that have detected lower levels of cocaine, amphetamine, and MDMA among those with dyed hair, 11,18–22 we did not find that dyed hair was significantly related to the level of cocaine and MDMA detection with all else being equal. Although bivariable differences in distribution did not yield significance, it may be noteworthy that those who dyed their hair had levels of cocaine detection on average three times lower than those who did not dye their hair.…”

“…[6][7][8][9][10][11][12][13] Indeed, effects of hair color may be minimal 17 considering that color did not affect any overall detection vs. no detection, but in some cases of minimal exposure, hair color may in fact make a difference between positive vs. negative detection, especially when standard detection cutoffs are utilized. 40,41 With respect to hair dyeing, unlike some other studies that have detected lower levels of cocaine, amphetamine, and MDMA among those with dyed hair, 11,[18][19][20][21][22] we did not find that dyed hair was significantly related to the level of cocaine and MDMA detection with all else being equal. Although bivariable differences in distribution did not yield significance, it may be noteworthy that those who dyed their hair had levels of cocaine detection on average three times lower than those who did not dye their hair.…”

The analysis of methylamphetamine and para‐hydroxy‐methylamphetamine in post‐mortem hair samples using liquid chromatography–tandem mass spectrometry

“…Cosmetic hair treatments are known to have deleterious effects on hair concentrations in users of MA. For example, the hair concentrations of MA exposed to hydrogen peroxide (6%) decreased ~ 67% over 24 h 40 . This is consistent with observations in the current study where MA and AMP concentrations decreased by 24–53% and 8–29%, respectively.…”

“…Cosmetic hair treatments are known to have deleterious effects on hair concentrations in users of MA. For example, the hair concentrations of MA exposed to hydrogen peroxide (6%) decreased ~ 67% over 24 h. 40 This is consistent with observations in the current study where MA and AMP concentrations decreased by 24–53% and 8–29%, respectively. In vitro experiments using high concentrations of MA (100,000 ng/ml) and hydrogen peroxide (30%) in solution incubated at 39°C for 24 h demonstrated a time‐dependent increase in the peak area of p ‐OH‐MA.…”

Utility of coloured hair for the detection of drugs and alcohol

“…Similarly for cocaine, the BE concentration at the 99th percentile in dyed or bleached hair is roughly half that for non‐treated hair; the amphetamineconcentration at the 95th percentile and the 99th percentile is roughly one‐third that in non‐treated hair, thus a reduction of 70%. It seems that here we find again the cosmetic treatment effects previously published in both in vitro and in vivo studies . So possibly, cosmetic treatment reduces the drug concentration, but only at high drug concentrations, represented in the population studied in this paper by the 95th percentile and higher.…”