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1.
Ecotoxicol Environ Saf ; 222: 112542, 2021 Oct 01.
Article de Anglais | MEDLINE | ID: mdl-34311424

RÉSUMÉ

Various cosmetic hair manipulations are known to interfere with the drug of abuse concentrations in hair. It is important to know the effects of cosmetic hair treatments as they may cause false-positive or false-negative results. The article aimed to investigate the effect of bleaching, perming, and dyeing treatment on the hair of methamphetamine(MA)abusers. The research results show that during the bleaching treatment, the content of MA in the hair is positively correlated with the degree of the treatment. Bleaching caused strong chemical degradation on MA, while perming exerted more a leaching out effect. Temporary dyes in single applications had only little effects on MA, Semi-permanent dyes can penetrate into the hair and exert a stronger matrix effect. The effect of permanent hair dye on the content of MA in hair mainly depends on the concentration of hydrogen peroxide.


Sujet(s)
Cosmétiques , Teintures capillaires , Métamfétamine , Poils , Teintures capillaires/toxicité , Humains , Détection d'abus de substances
2.
Forensic Sci Int ; 297: 270-276, 2019 Apr.
Article de Anglais | MEDLINE | ID: mdl-30851603

RÉSUMÉ

Various cosmetic hair manipulations are known to interfere with drug of abuse concentrations in hair. It is important to evaluate the effects of cosmetic hair treatments as they can influence quantitative hair results. Only one study showed a significant decrease of THC after bleaching and coloring. The aim of the study was to investigate the effect of bleaching, perming and dyeing treatment on d-9-tetrahydrocannabinol (THC), but also Cannabidiol (CBD), Cannabinol (CBN) and 11-nor-D9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in hair. Thirty THC-positive hair samples were selected in this study. A single hair lock was divided in 2 separate locks and the proximal 3 cm segment was analyzed. One lock served as control while the other lock was bleached, permed or dyed respectively. Hair was analyzed using a routine method including cleaning, treatment of hair with NaOH and 2 different SPE extractions for THC, CBN, CBD and THC-COOH respectively. Analysis was performed with routine methods using GC/MS-MS in electron impact (EI) mode for THC, CBN and CBD or negative chemical ionization (NCI) mode for THC-COOH after PTV-injection. Bleaching and perming reduced all cannabinoids concentration in hair; THC was more affected than THC-COOH, CBN and CBD. Bleaching caused strong chemical degradation on cannabinoids, while perming exerted more a leaching out effect. Permanent colorings in single applications had only little effects on cannabinoids. Finally this study highlights the importance of considering bleaching and perming for the correct interpretation of hair results.


Sujet(s)
Cannabinoïdes/analyse , Techniques cosmétiques , Décolorants capillaires , Teintures capillaires , Poils/composition chimique , Détection d'abus de substances , Chromatographie gazeuse-spectrométrie de masse , Humains , Limite de détection , Reproductibilité des résultats
3.
Forensic Sci Int ; 297: 184-188, 2019 Apr.
Article de Anglais | MEDLINE | ID: mdl-30802647

RÉSUMÉ

Hair analysis plays an important role in abstinence control in forensic toxicology. However, hair coloration affects the concentrations of xenobiotics and may lead to false negative results. For instance, henna has been shown to decrease ethyl glucuronide concentrations in hair. For analysis of the main henna ingredient lawsone (2-hydroxy-1,4-naphthoquinone), hair samples were washed, cut into small pieces (less than 5 mm), incubated (20 mg) in water and with internal standard (theophylline) for 24 h at 37 °C. Lawsone was analyzed in the supernatant using liquid chromatography with diode array detection. For quantitative assay, the absorption at 280 nm was found to be linear up to 250 ng/mg hair. The detection limit of lawsone was 2.2 ng/mg, precision and accuracy were better than 6%. Lawsone was only detectable in 12 henna-colored hair samples in concentrations from 27.3 to 253.7 (median 92.6) ng/mg. The analysis of lawsone is recommended in cases of suspected hair coloration where assessment of oxidative treatment was negative (e.g. no increase of 1H-pyrrole-2,3,5-tricarboxylic acid (PTCA) and unobtrusive fluorescence microscopy).


Sujet(s)
Teintures capillaires/analyse , Poils/composition chimique , Naphtoquinones/analyse , Chromatographie en phase liquide , Toxicologie médicolégale , Humains , Microscopie de fluorescence
4.
Drug Test Anal ; 10(4): 768-773, 2018 Apr.
Article de Anglais | MEDLINE | ID: mdl-28940782

RÉSUMÉ

Hair analysis for the assessment of alcohol or drug abstinence has become a routine procedure in forensic toxicology. Hair coloration leading to loss of incorporated xenobiotics and to false negative results has turned out to be a major problem. Currently only colored extracts provide hints of manipulations but not bleaching. A liquid chromatographic-tandem mass spectrometric (LC-MS/MS) method was developed and validated to determine 1H-pyrrole-2,3,5-tricarboxylic acid (PTCA), a major oxidation product of melanin. PTCA was determined in natural hair samples (n = 21) after treatment with 3% hydrogen peroxide (H2 O2 ) for 30 or 40 minutes with concentrations up to 12% for 40 minutes. In another series, 12 natural hair samples were submitted to different coloration procedures (henna, tinting, semi-permanent and permanent dyeing, bleaching) and the changes in PTCA content were determined. A significant increase in the PTCA content was found for both incubation times and increasing H2 O2 concentrations. Coloration with henna or tinting had no influence on PTCA levels detected, but a significant increase was observed after semi-permanent and permanent dyeing and bleaching. As PTCA concentrations in natural hair were found to be in a range of <2.1-16.4 ng/mg (8.4 ± 3.8 ng/mg, mean ± SD, n = 33), a cut-off of 20 ng/mg is recommended for the distinction between natural vs. excessively oxidized hair. In case of naturally low melanin content (light-blond or white hair), no marked increase in PTCA may occur. The present study demonstrated that PTCA is formed during oxidative treatment of melanin in hair, which can be used to detect previous hair coloration including oxidation.


Sujet(s)
Poils/composition chimique , Mélanines/analyse , Pyrroles/analyse , Spectrométrie de masse en tandem/méthodes , Marqueurs biologiques/analyse , Chromatographie en phase liquide à haute performance/méthodes , Toxicologie médicolégale/méthodes , Poils/effets des médicaments et des substances chimiques , Poils/métabolisme , Produits capillaires/métabolisme , Humains , Peroxyde d'hydrogène/métabolisme , Mélanines/métabolisme , Oxydoréduction/effets des médicaments et des substances chimiques , Stress oxydatif/effets des médicaments et des substances chimiques , Pyrroles/métabolisme , Détection d'abus de substances/méthodes
5.
Drug Test Anal ; 10(1): 177-183, 2018 Jan.
Article de Anglais | MEDLINE | ID: mdl-28407398

RÉSUMÉ

Ethyl glucuronide (EtG) is increasingly used in forensic toxicology as a marker for alcohol use in analyses of hair samples, especially in abstinence control. Some cosmetic treatments are considered to markedly reduce the EtG content. In view of especially many women with coloured hair the present study was performed to further investigate the effect of a variety of colouring procedures (bleaching, tinting, permanent and semi-permanent dyeing, henna) on the EtG content. Untreated hair samples (n = 12, EtG 13.9-64.7 pg/mg) were re-analyzed (gas chromatography- negative chemical ionization mass spectrometry, 0.8 pg/mg quantification limit) after different treatment procedures. A decrease of the EtG content of at least 10% occurred in every case. The reduction in comparison to the untreated hair was expectedly high for permanent dyeing and bleaching with 18.1% of the initial content (median, range 0.0-50.9%) and 18.4% (0.0-46.7%), respectively. For henna this was 38.3% (0.0-83.0%), for tinting 70.4% (29.0-90.8%), for semi-permanent dyeing 41.9% (0.0-77.4%). With permanent hair dye the EtG content was decreased to below 7 pg/mg in 10 of 12 cases, in 3 cases even below the LOD (0.2 pg/mg). Surprisingly henna treatment without oxidative component had a marked influence, EtG was below 2 pg/mg in 2 of 12 samples. The study showed that all tested coloration procedures markedly affected the deposited EtG content. Even temporary or henna coloration may have a marked effect. The present data support the recommendation to exclude hair samples with colour manipulations for analysis on the EtG content as a precaution in alcohol abstinence programs. Copyright © 2017 John Wiley & Sons, Ltd.


Sujet(s)
Glucuronates/analyse , Décolorants capillaires/pharmacologie , Teintures capillaires/pharmacologie , Poils/composition chimique , Poils/effets des médicaments et des substances chimiques , Détection d'abus de substances/méthodes , Alcoolisme/diagnostic , Alcoolisme/métabolisme , Toxicologie médicolégale/méthodes , Toxicologie médicolégale/normes , Poils/métabolisme , Humains , Détection d'abus de substances/normes
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