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1.
Forensic Sci Int ; 302: 109894, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31408788

RESUMO

INTRODUCTION: Currently, hair straightening has become a regular hair treatment for women but likewise for men. Several studies have shown that thermal straightening has an influence on the concentration of ethyl glucuronide and of drugs of abuse content in hair. Heat treatment of hair may decrease concentrations of cocaine (COC) and of cocaethylene (CE) in hair and increase concentrations of benzoylecgonine (BZE). The goal of this study was to evaluate the influence of thermal straightening on anhydroecgonine methyl ester (AEME), a known cocaine smoking marker, in hair. METHOD: 42 positive COC hair samples were treated in vitro with iron plates heated to 200°C. During this treatment one lock of hair was put sequentially 30 times in contact with a hair straightener during 2s, the other lock was not treated. The hair samples were analyzed by a validated GC/MS method for AEME, COC and its metabolites BZE, norcocaine (NC), ecgonine methyl ester (EME) and CE. RESULTS: After treatment, a median increase of concentrations was observed for AEME (110.3%) and BZE (27.6%) whereas a median decrease was found for COC (56.9%), NC (46.7%), EME (33.3%) and CE (41.7%). The median BZE/COC ratio of 0.6 in not treated hair increased to 1.5 in treated hair. CONCLUSION: Regarding our in vitro results, AEME may be produced by thermal hair straightening. Therefore, the presence of AEME in hair should not be used as an irrefutable prove of cocaine smoking. Our study shows that for the interpretation of AEME results in hair, potential heat treatment of hair should be considered. A ratio BZE/COC higher 1 appears to be a good marker to identify thermal treatment of hair before collection. Finally, thermal straightening should be documented during hair collection and should also be considered for the interpretation of COC results in hair.


Assuntos
Cocaína/análogos & derivados , Cocaína/análise , Preparações para Cabelo , Cabelo/química , Entorpecentes/análise , Biomarcadores/análise , Transtornos Relacionados ao Uso de Cocaína/diagnóstico , Toxicologia Forense , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Técnicas In Vitro , Detecção do Abuso de Substâncias
2.
Forensic Sci Int ; 297: 270-276, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30851603

RESUMO

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.


Assuntos
Canabinoides/análise , Técnicas Cosméticas , Descolorantes de Cabelo , Tinturas para Cabelo , Cabelo/química , Detecção do Abuso de Substâncias , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Limite de Detecção , Reprodutibilidade dos Testes
3.
Forensic Sci Int ; 292: 163-166, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30317054

RESUMO

Medical cannabis is becoming increasingly popular for many different ailments and improvement of general well-being. Particularly CBD-rich extracts are easily available via online pharmacies, health stores or directly from producers. However, almost all of the extracts contain small amounts of THC. Thus, in case of continuous or heavy use of CBD rich cannabis, THC concentrations in hair may rise above accepted legal limits. In our study, we investigated THC, CBN and CBD in hair samples from regular CBD rich cannabis users. The goals were to determine levels of the cannabinoids in hair and to evaluate a possible correlation between regular CBD intake and CBD levels in hair. All participants consumed cannabis extracts from the same producer. It contained CBD at different concentrations and small amounts of THC with a CBD/THC concentration ratio of 30. The self-declared CBD dosage ranged from 4 to 128mg CBD/day, corresponding to a daily THC intake of 0.1 to 4.3mg. After extraction and derivatization, hair samples were analysed using a validated GC/MS-MS method. CBD concentrations ranged from 10 to 325pg/mg of hair, but no significant correlation was observed between CBD concentrations and the daily dose. THC was detected in one sample only at a concentration below our cut-off, whereas CBN was not detected. In this study, we showed that even after repeated consumption of CBD-rich cannabis extracts in medium to high doses, consumers are generally tested negative for THC in hair.


Assuntos
Canabinoides/análise , Cabelo/química , Maconha Medicinal/administração & dosagem , Administração Sublingual , Adulto , Idoso , Cromatografia Gasosa , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem
4.
Forensic Sci Int ; 291: 193-198, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30218866

RESUMO

Gamma-hydroxybutyric acid (GHB) is a short-chain fatty acid used recreationally as a drug of abuse due its strong suppressive effect on the central nervous system. The detection window of GHB in blood and urine is very narrow (t1/2=30min) but can be substantially prolonged using alternative matrices such as hair. We here present a newly developed and limited validated method with a solid phase extraction (SPE) using GC-MS/MS to determine concentrations of GHB in hair samples. The soft extraction technique (water and 90min ultrasonic bath) preserves GHB with a high yield and clean extracts. In addition, endogenous GHB can be detected in hair of non-GHB users. However, little is known about GHB concentrations in hair of abstinent, frequent and chronic GHB users. Therefore, we present data from hair samples of healthy volunteers to evaluate the proposed endogenous GHB ranges, and from GHB-dependent patients to address GHB concentrations in hair with GHB intake. In 20 non-GHB users, a mean endogenous concentration of 1.1±0.6ng/mg hair (range of 0.3-2ng/mg) was found. In GHB-dependent patients, concentrations between 6.3-239.6ng/mg hair were found, with no correlation between concentrations in hair and dose of GHB intake. In summary, we present a new and limited validated method, adequately sensitive for the detection of GHB in hair, as well as first-time measurements of GHB concentrations in dependent patients in order to better understand the relationship between the frequency of use/dose and concentrations observed in hair samples.


Assuntos
Cabelo/química , Oxibato de Sódio/análise , Detecção do Abuso de Substâncias/métodos , Feminino , Toxicologia Forense/métodos , Cromatografia Gasosa-Espectrometria de Massas , Voluntários Saudáveis , Humanos , Masculino , Reprodutibilidade dos Testes , Extração em Fase Sólida , Transtornos Relacionados ao Uso de Substâncias/diagnóstico
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