Validation of a method to detect cocaine and its metabolites in nails by gas chromatography-mass spectrometry.

The objective of the present work was to compare previously published methods and provide validation data to detect simultaneously cocaine (COC), benzoylecgonine (BE) and norcocaine (NCOC) in nail. Finger and toenail samples (5mg) were cut in very small pieces and submitted to an initial procedure for external decontamination. Methanol (3 ml) was used to release analytes from the matrix. A cleanup step was performed simultaneously by solid-phase extraction (SPE) and the residue was derivatized with pentafluoropropionic anhydride/pentafluoropropanol (PFPA/PFP). Gas chromatography-mass spectrometry (GC-MS) was used to detect the analytes in selected ion monitoring mode (SIM). Confidence parameters of validation of the method were: recovery, intra- and inter-assay precision, as well as limit of detection (LOD) of the analytes. The limits of detection were: 3.5 ng/mg for NCOC and 3.0 ng/mg for COC and BE. Good intra-assay precision was observed for all detected substances (coefficient of variation (CV)<11%). The inter-assay precision for norcocaine and benzoylecgonine were <4%. For intra- and inter-assay precision deuterated internal standards were used. Toenail and fingernail samples from eight declared cocaine users were submitted to the validated method.

Detection of cocaine and cocaethylene in sweat by solid-phase microextraction and gas chromatography/mass spectrometry.

In the present work, a semi-quantitative method was developed to detect simultaneously cocaine (COC) and cocaethylene (CE) (transesterification product of the coingestion of COC with ethanol) in sweat. Sweat samples were collected by means of a non-occlusive sweat patch device supplied by PharmChek. The method was based on the dissolution of COC and CE incorporated into the patch, with 0.2 M sodium acetate buffer (pH 5.0) and the extraction of the analytes by solid-phase microextraction (SPME). Gas chromatography/mass spectrometry (GC-MS) was used to detect the analytes in selected ion monitoring mode (SIM). The method showed to be very simple, rapid and sensitive. The limits of detection were 5 ng/ml for COC and CE (12.5 ng/patch). Good inter and intra-assay precision was also observed (coefficient of variation <8%) with the use of deuterated internal standards.

Drug abuse among workers in Brazilian regions.

OBJECTIVE: Many business organizations in Brazil have adopted drug testing programs in the workplace since 1992. Rehabilitation, rather than layoff and disciplinary measures, has been offered as part of the Brazilian employee assistance programs. The purpose study is to profile drug abuse among company workers of different Brazilian geographical regions. METHODS: Urine samples of 12,700 workers from five geographical regions were tested for the most common illicit drugs of abuse in the country: marijuana, cocaine, and amphetamine. Enzyme multiplied immunoassay technique (EMIT) and gas chromatography coupled with mass spectrometry (GC/MS) were the techniques utilized for urine testing. The distribution of collected urine samples according to geographical regions was: 72.0% southeast, 13.8% northeast, 7.9% south, 5.7% central west and 0.6% north. RESULTS: Of all samples analyzed, 1.8% was found to be positive for drugs: 0.5% from the south region, 1.1% from northeast, 1.2% from central west, 1.3% from north, and 2.2% from southeast. Of these, 59.9% was marijuana, 17.7% cocaine, 14.6% amphetamine, and 7.7% associated drugs. CONCLUSIONS: The distribution of drugs found in the samples shows a regional variation. Marijuana, however, was found in all regions. Cocaine was seen only in central west and southeast regions. Amphetamine was found in northeast, central west, and southeast regions.

Drug abuse among workers in Brazilian regions

OBJETIVO: No Brasil, desde 1992, inúmeras empresas comerciais e industriais vêm adotando programas de controle do uso de drogas de abuso no ambiente de trabalho. Nenhuma medida disciplinar ou demissionária é tomada sem antes se tentar a reabilitação do funcionário. O objetivo do estudo é apresentar o perfil do uso de drogas de abuso entre trabalhadores de diferentes empresas brasileiras. MÉTODOS: Amostras de urina de 12.700 indivíduos provenientes das cinco regiões geográficas brasileiras foram analisadas visando à detecção das principais drogas de abuso utilizadas no País: cocaína, maconha e anfetamina. A técnica de enzimaimunoensaio (EMIT) foi usada como análise de triagem para as substâncias pesquisadas. A confirmação dos resultados foi realizada pela espectrometria de massa associada à cromatografia em fase gasosa (GC/MS). A distribuição das amostras de acordo com as regiões geográficas foi: 72,0 por cento foram coletadas na região Sudeste, 13,8 por cento no Nordeste, 7,9 por cento originaram-se na região Sul, 5,7 por cento no Centro-Oeste e 0,6 por cento na região Norte. RESULTADOS: Os resultados obtidos foram: 1,8 por cento de todas as amostras analisadas foram positivas para a presença de drogas de abuso, sendo que 0,5 por cento eram provenientes da região Sul, 1,1 por cento da região Nordeste, 1,2 por cento do Centro-Oeste, 1,3 por cento da região Norte e 2,2 por cento do Sudeste. A freqüência com que as diferentes drogas foram encontradas foi: 59,9 por cento para maconha, 17,7 por cento para cocaína, 14,6 por cento para anfetamina e 7,7 por cento para drogas em associação. CONCLUSÕES: A distribuição das drogas de abuso detectadas apresentou variações regionais. A maconha foi encontrada nas amostras de todas as regiões; a cocaína estava presente somente em amostras oriundas das regiões Centro-Oeste e Sudeste. A anfetamina foi detectada nas amostras provenientes do Nordeste, Centro-Oeste e Sudeste.

Determination of cocaine, benzoylecgonine and cocaethylene in human hair by solid-phase microextraction and gas chromatography-mass spectrometry.

The present work describes a highly precise and sensitive method developed to detect cocaine (COC), benzoylecgonine (BE, its main metabolite) and cocaethylene (CE, transesterification product of the coingestion of COC with ethanol) in human head hair samples. The method was based on an alkylchloroformate derivatization of benzoylecgonine and the extraction of the analytes by solid-phase microextraction (SPME). Gas chromatography-mass spectrometry (GC-MS) was used to identify and quantify the analytes in selected ion monitoring mode (SIM). The limits of quantification and detection (LOQ and LOD) were: 0.1 ng/mg for COC and CE, and 0.5 ng/mg for BE. Good inter- and intra-assay precision was observed. The dynamic range of the assay was 0.1-50 ng/mg. The method is not time consuming and was shown to be easy to perform.

Solid-phase micro-extraction-gas chromatography-mass spectrometry and headspace-gas chromatography of tetrahydrocannabinol, amphetamine, methamphetamine, cocaine and ethanol in saliva samples.

In the present work, a method was developed aiming at the serial detection of tetrahydrocannabinol (THC), amphetamine, methamphetamine, cocaine and ethanol in saliva. Saliva samples were submitted to an initial headspace procedure for ethanol determination by gas chromatography/flame ionization detector (GC-FID). After this step, two consecutive solid-phase micro-extractions (SPME) were carried out: THC was extracted by submersing a polydimethylsiloxane fiber (100 micro m) in the vial for 20 min; amphetamine, methamphetamine and cocaine were subsequently extracted after alkalinization. Derivatization of the amphetamines was carried out directly in the solution by adding 2 micro l of butylchloroformate. Gas chromatography-mass spectrometry (GC-MS) was used to identify the analytes in selected ion monitoring (SIM) mode. Confidence parameters of validation of the method were: recovery, linearity, intra- and inter-assay precision as well as limits of detection and quantification of the analytes. The limits of quantification (LOQ) obtained were: ethanol (0.010 g/l); amphetamine (5.0 ng/ml); methamphetamine (0.5 ng/ml); cocaine (5 ng/ml) and THC (5 ng/ml). The method proved to be highly precise (coefficient of variation<8%) for all detected substances.

Identificação de anfetamina em amostras de cabelo por imunofluorescência polarizada / Amphetamine detection in hair samples by FPIA

O uso indevido de anfetaminas tem preocupado as autoridades sanitárias em todo o mundo. No Brasil, destacam-se os anorexígenos anfetamínicos como o femproporex, que, no organismo, se biotransforma em anfetamina. Apesar de ser controlado por legislação específica, este fármaco tem sido amplamente utilizado em nosso país. Nas análises toxicológicas para verificação do uso de fármacos e drogas de abuso, têm-se empregado diferentes amostras biológicas. Mais recentemente a utilização do cabelo tem sido preconizada principalmente por informar sobre um uso a longo prazo da substância. A técnica para identificação de anfetaminas em cabelo é a cromatografia em fase gasosa acoplada à espectrometria de massas (CG-EM)...

Confirmation of cocaine exposure by gas chromatography-mass spectrometry of urine extracts after methylation of benzoylecgonine.

Volatility and thermal stability are necessary physical-chemical properties for analysing a substance by gas chromatography. A derivatization step is required before gas chromatography of benzoylecgonine (the main metabolite of cocaine). In the literature, reactions such as silylation, perfluoroalkylation or alkylation are the most frequently used to derivatize benzoylecgonine. However, they allow the formation of products sensitive to moisture or require a purification step. So, a procedure to derivatize benzoylecgonine with diazomethane before gas chromatographic analysis was evaluated. A study was performed to evaluate the efficiency of conversion of benzoylecgonine in cocaine, the necessary time for reaction and the stability of ethereal solution of diazomethane. The reaction was shown to be very fast in mild conditions and there was no need for a further purification step. When benzoylecgonine was extracted from urine by solid-phase extraction and derivatized with diazomethane, concentrations as low as 25 ng/ml could be detected using GC-MS in the full scan mode.

[Blood alcohol content prevalence among trauma patients seen at a level 1 trauma center]. / Prevalência de alcoolemia em vítimas de causas externas admitidas em centro urbano de atenção ao trauma.

OBJECTIVE: To investigate the prevalence of blood alcohol content (BAC) among patients seen at a level 1 trauma center. METHODS: A cross-sectional study was carried out and patients were randomly selected at the emergency room of a level I trauma center in the city of São Paulo, Brazil, throughout a year (August 1998 to August 1999). Blood samples were drawn and data was collected using an adapted version of a questionnaire developed by the Medical Research Institute of San Francisco - Alcohol Research Group. RESULTS: A population sample of 464 patients was analyzed. Most of them were males (73.7%) and the median age was 29 years old. Positive BAC was found in 28.9% of the cases (CI95% 24.8 - 33.2) and in 84.3% BAC was =0.10%. Type of injury, gender, age group, marital status and outcome showed statistically significant associations with BAC with the highest BAC prevalence observed among assault victims (46.2%), males (33.9%), 25 to 44 years old (37.6%), singles (33.0%), and patients admitted in the hospital (41.4%). CONCLUSIONS: The results reinforce the relationship of alcohol and trauma. Preventive actions at different levels focusing on higher risk groups for alcohol-related injuries should be considered as part of prevention programs to both reduce injuries and curb recurrent events.

Utilização da imunofluorescência polarizada na determinação de benzoilecgonina em cabelo de usuários de cocaína / Using of fluorescence polarization imunnoassay in a detection of benzoylecgonine in cocaine users'hair

A imunofluorescência polarizada (IFP) é uma técnica de triagem recomendada para a determinação de benzoilecgonina, produto de biotransformação da cocaína, em urina de usuários deste fármaco. Foi investigada a possibilidade da aplicação da IFP para verificar o uso de cocaína analisando amostras de cabelo. Como nesse espécime biológico é encontrada maior concentração de cocaína do que de benzoilecgonina, foi desenvolvido um método capaz de promover a extração das duas substâncias e a posterior transformação da cocaína em benzoilecgonina. O método padronizado foi aplicado em amostras de cabelo provinientes de usuários de cocaína, sendo obtidos resultados positivos para benzoilecgonina em todas as análises realizadas...

Determinaçäo do período de detecçäo de benzoilecgonina urinária por imunofluorescência polarizada em usuários de cocaína sob condições de exposição não controladas / Determination of detection period of urinary benzoylecgonine through fluorescence polarization immunoassays in cocaine users under non controlled exposition

A determinação da benzoilecgonina urinária é um parâmetro utilizado para verificar a exposição recente à cocaína. Relatos encontrados na literatura especializada indicam que esse produto de biotransformação da cocaína pode ser detectado na urina de 24 horas a 22 dias. A maioria dessas pesquisas foi realizada em condições de exposição controladas e não reflete a realidade de uso da droga. O trabalho tem como objetivo determinar o período de detecção de benzoilecgonina urinária em usuários de cocaína, com exposições não controladas. Cinquenta e sete pacientes internados numa clínica para tratamento da farmacodependência, que utilizaram cocaína até 72 horas anteriores à internação, forneceram amostras de urina durante 10 dias consecutivos...

Indicacoes e limites das analises toxicologicas para substancias psicoativas / Indications and limits for the toxicological analysis for psychoatives substances

O consumo de substancias psicoativas no Brasil avoluma-se a cada ano, constituindo um grave problema de saude publica e exigindo a aplicacao de recursos para minimiza-lo, sendo a prevencao a melhor estrategia para evitar determinado problema. Os esforcos preventivos, porem, nao devem restringir-se apenas a realizacao de analises toxicologicas para verificar o uso de drogas...

Inalantes de abuso: exposiçäo humana e efeitos tóxicos / Inhalant abuse: human exposure and toxic effects

A literatura sobre os inalantes de abuso é revisada com o objetivo de apresentar painel sobre as características dos usuários, da exposiçäo, da toxicocinética e dos efeitos tóxicos. Säo relacionados os principais produtos utilizados com essa finalidade e seus componentes voláteis