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Publications (4)4.21 Total impact

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    ABSTRACT: A major marijuana metabolite, 11-nor-9-carboxy-tetrahydrocannabinol (THCA), has been identified in oral fluids from donors that previously tested positive for Delta(9)-tetrahydrocannabinol (THC). The method consisted of solid-phase extraction of the oral fluid samples followed by gas chromatography-tandem mass spectrometry analysis of the extracts. Testing for THCA was performed on 223 oral fluid samples previously analyzed for THC. The THCA assay was linear from 10 to 240 pg/mL. The mean recovery of spiked THCA in oral fluid was 104%, and precision was 4% at 20 pg/mL using fortified negative samples. This method was rugged and robust, providing detection and quantification of THCA in oral fluids at levels not previously reported. Results of this study showed that THCA was detectable in 21 of 26 oral fluid samples previously reported positive for THC. The range of concentrations from these samples was from 10 pg/mL up to 142 pg/mL THCA.
    Journal of analytical toxicology 01/2006; 30(9):645-50. · 2.11 Impact Factor
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    ABSTRACT: The use of prescription drugs, including synthetic opiates, is increasing in the U.S., with emergency room reports showing a dramatic rise in prescription opiate abuse. As part of an ongoing study, the hair of admitted opiate users was analyzed for hydrocodone and hydromorphone, as well as codeine, morphine, and 6-acetylmorphine in order to determine if there was any correlation between self-reported frequency of opiate intake and the concentration of drug detected in hair. The hairs were confirmed using gas chromatography-mass spectrometry following screening by enzyme linked immunosorbent assay (ELISA). Twenty-four hair specimens collected from volunteers showed the presence of hydrocodone (130-15,933 pg/mg); four of those also contained hydromorphone (59-504 pg/mg). The specimens were also analyzed for morphine, codeine, and 6-acetylmorphine. Hair specimens from five self-reported codeine users showed concentrations of hydrocodone between 592 and 15,933 pg/mg. In addition, codeine was present at concentrations of 575-20,543 pg/mg, but neither morphine nor hydromorphone were present in any of those hair specimens. Though the analysis of some opiates in hair has been previously published, this is the first study where the hydrocodone and hydromorphone concentrations have been measured following self-reported opiate intake.
    Journal of analytical toxicology 01/2006; 30(6):353-9. · 2.11 Impact Factor
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    ABSTRACT: Proposed revisions to the Federal guidelines, which include the potential use of hair and oral fluid, as well as urine, for workplace drug testing were published in 2004. This study was designed to determine the positivity rate in various specimen types, both in a drug using population and a population denying cocaine use. The study enrolled 200 subjects, half of whom admitted to cocaine use, half who did not. Each subject provided a urine sample, an oral fluid and a hair specimen taken from the head at the time of interview. Information on drug use, including time of last use, frequency of use, ethnicity, age, sex and hair color were recorded for each subject. The specimens were analyzed for cocaine and/or its metabolites depending on the matrix and the data is presented. Hair identified the highest number of drug users in both the admitted using population and those who denied use. Oral fluid and urine gave similar detection rates in both populations, with oral fluid slightly better in the self-reported non-using population, and urine slightly better in the self-reported cocaine user population. This is the first study where hair, oral fluid and urine were collected simultaneously from a drug using population. Hairis the most likely matrix to identify cocaine users. Des révisions proposées aux directives fédérales incluant l'utilisation potentielle des cheveux, de la salive ainsi que des urines pour le dépistage des conduites addictives en entreprise ont été publiées en 2004. Cette étude a été conçue pour déterminer le taux de positivité de différents types d'échantillons, dans une population toxicomane et dans une autre niant sa consommation de cocaïne. Cette étude a été menée sur 200 sujets, la moitié admettant une consommation de cocaïne, l'autre moitié la niant. Chaque sujet a donné un échantillon d'urine, de salive et de cheveux prélevés au moment de l'entrevue. Pour chaque sujet, des informations sur leur consommation de stupéfiants, incluant le moment de la dernière prise et la fréquence de consommation, leur appartenance ethnique, leur âge, leur sexe et la couleur de leurs cheveux ont été enregistrés. Les échantillons ont été analysés pour la cocaïne et/ou ses metabolites selon la matrice. Les résultats sont présentés ci-dessous. Les cheveux ont identifié le plus grand nombre de toxicomânes dans les deux populations. La salive et les urines ont donné des taux de détection similaires dans les deux populations, avec une meilleure détection dans la salive pour la population se disant saine et une meilleure détection dans les urines pour la population s'admettant consommatrice de cocaïne. C'est la première étude où des cheveux, de la salive et des urines ont été collectés simultanément sur une population toxicomane. Le cheveu est la matrice la plus appropriée pour identifier des consommateurs de cocaïne.
    http://dx.doi.org/10.1051/ata:2005003. 01/2005;
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    ABSTRACT: Proposed revisions to the Federal guidelines, which include the potential use of hair and oral fluid, as well as urine, for workplace drug testing were published in the Federal Register in 2004. This study was designed to determine the positivity rate in various specimen types, both in a drug using population and a population denying methamphetamine use. The study enrolled 200 subjects, half of whom admitted to methamphetamine use, halfwho did not. Each subject provided a urine sample, an oral fluid and a hair specimen taken from the head at the time of interview. Information on drug use, including time of last use, frequency of use, ethnicity, age, sex and hair color were recordedfor each subject. The hair specimens were analyzed for methamphetamine, amphetamine, 3-4 methylenedioxy-methamphetamine (MDMA), its metabolite methylenedioxy-amphetamine (MDA) and methylenedioxy ethylamphetamine (MDEA). The oral fluid specimens were confirmedfor the presence of methamphetamine, amphetamine, MDMA and MDA. Hair identified the highest number of drug users in both the admitted using population and those who denied use. Urine identified a higher number of positive subjects than oral fluid. While the analysis of amphetamines in hair, oral fluid and urine has been previously published, this is the first study where all three matrices were collected simultaneouslyfrom a drug using population, and analyzed according to the proposed Federal guidelines. Des révisions proposées aux directives fédérales incluant l'utilisation potentielle des cheveux, de la salive ainsi que des urines pour le dépistage des conduites addictives en entreprise ont été publiés dans le registre fédéral en 2004. Cette étude a été conçue pour déterminer le taux de positivité de différents types d'échantillons dans une population toxicomane et dans une autre niant sa consommation de methamphetamine. Cette étude a été menée sur 200 sujets, la moitié admettant une consommation de methamphetamine, l'autre moitié la niant. Chaque sujet a donné un échantillon d'urine, de salive et de cheveux prélevés au moment de l'entrevue. Pour chaque sujet, des informations sur, leur consommation de stupéfiants, incluant la fréquence de consommation, leur appartenance ethnique, leur âge, leur sexe et la couleur de leurs cheveux ont été enregistrées. Les échantillons ont été analysés pour la methamphetamine, l'amphétamine, la 3-4 méthylendioxy- methamphetamine (MDMA), son metabolite la méthylendioxy-amphétamine (MDA) et la méthylendioxy éthylamphétamine (MDEA). Les échantillons de salive ont servi à valider la présence de methamphetamine, d'amphétamine, de MDMA et de MDA. Les cheveux ont identifiés le plus grand nombre de toxicomanes dans les deux populations. Les urines ont permis d'identifier un plus grand nombre de sujets positifs que la salive. Bien que l'analyse des amphétamines dans les cheveux, la salive et les urines aient déjà été publiée, c'est la première étude où les trois matrices ont été collectées simultanément sur une population toxicomane et analysées en suivant les directives fédérales.
    http://dx.doi.org/10.1051/ata:2005004. 01/2005;