Low concentrations of methamphetamine detectable in urine in the presence of high concentrations of amphetamine.

Twenty-two urine specimens reported by military drug-testing laboratories for the presence of high concentrations of amphetamine only were subject to further analysis for the presence of methamphetamine. The 22 urine specimens had concentrations of amphetamine in the range of 28,028 to 241,142 ng/mL. The specimens were also assayed for the respective isomeric ratio of d (S) and l (R) amphetamine and methamphetamine. The results suggest that urine specimens containing high concentrations of amphetamine in which the urine concentration ratio of methamphetamine to amphetamine is less than 0.5% with similar isomeric distribution of d-(S) and l-(R) amphetamine and methamphetamine, respectively, may not necessarily indicate polydrug use.

Concentration distribution of the marijuana metabolite Delta9-tetrahydrocannabinol-9-carboxylic acid and the cocaine metabolite benzoylecgonine in the department of defense urine drug-testing program.

Urine drug testing has been employed for punitive purposes by the Department of Defense since December 1981 (Memorandum 62884, Deputy Secretary of Defense Frank C. Carlucci). Federal Workplace Drug Testing Programs were initiated in response to Executive Order 12564 issued on September 15, 1986, that required Drug-Free Federal Workplaces be established. In their respective programs, a positive urine drug test may be referred to a military court martial or to an administrative board. To address safety and insurance requirements, the testing of civilians has expanded beyond Federal Programs to include pre-employment and post-accident urine drug testing. During adjudication, an Expert Toxicologist may be asked to opine what can be discerned from the concentration of drug or drug metabolite found in the urine. Little can be opined with certainty from a positive urine drug test as to the amount of drug ingested, when the drug was ingested, and in most instances, whether the individual felt the effects of the drug, or was under the influence of the drug found in the urine. What may be useful to both the Expert and to the Trier-of-Facts is the frequency that a particular urine drug concentration is encountered in positive drug tests. The finding that 50% of all positive marijuana and cocaine urine metabolite concentrations in the military testing program over the three-year period of October 1, 2004 through September 30, 2007, are below a median value of 65 and 968 ng/mL, respectively, provide reference points. A median drug concentration combined with the percentile or frequency that a particular urine drug concentration occurs may provide evaluative information for a determination of the facts and the outcome of judicial or administrative proceedings. This may be especially useful to jurors when the concentration of marijuana or cocaine metabolite is perceptibly low. The information would also be applicable to medical review officers, medical examiners, drug treatment professionals, probation officers, and program analysts coordinating drug policy decisions.

Evaluation of four immunoassay screening kits for the detection of benzodiazepines in urine.

The identification of benzodiazepines (BZD) in biological fluids can be a challenging process. The large number of various BZD in pharmaceutical distribution, with similar core structures, and individual metabolic profiles all contribute to a complicated and time-consuming analysis. The purpose of the current study was to evaluate the performance of four commercially available immunoassay urine screening kits for use in a forensic urine analysis testing program. The four kits included the Roche Benzodiazepine Plus KIMS assay, Microgenics CEDIA Benzodiazepine assay, Microgenics CEDIA high sensitivity assay with beta-glucuronidase, and Microgenics DRI reagent ready Benzodiazepine assay. Each kit was evaluated for linearity, precision, accuracy, carryover, reagent specificity, and confirmation rates. BZD reagent specificity was compared by analysis of 55 structurally dissimilar compounds to BZD. Negative responses to all 55 compounds were elicited by all four reagent assays. Cross-reactivity for the assays was demonstrated by detecting 27 structurally similar BZD. In addition, greater than 10,000 randomly collected urine samples were screened at a 200 ng/mL cutoff for each assay. Positive samples were confirmed by gas chromatography-mass spectrometry using a panel of 13 BZD confirmation standards. The Microgenics CEDIA high sensitivity assay demonstrated the highest positive screening rate as well as the highest confirmation rate of the four assays.

Enantiomeric separation and quantitation of (+/-)-amphetamine, (+/-)-methamphetamine, (+/-)-MDA, (+/-)-MDMA, and (+/-)-MDEA in urine specimens by GC-EI-MS after derivatization with (R)-(-)- or (S)-(+)-alpha-methoxy-alpha-(trifluoromethy)phenylacetyl chloride (MTPA).

In drug testing, the presence of methamphetamine in urine is generally confirmed by a gas chromatography-mass spectrometry (GC-MS) method. Derivatization of the compound to a perfluoroalkylamide, prior to confirmation, typically yields better chromatographic separation. Once methamphetamine is detected, a second GC-MS test is necessary to distinguish positive results from the use of over-the-counter medication, Vicks inhaler, or from use of a prescription drug, selegiline (Deprenyl). R-(-)-Methamphetamine is the urinary product from legitimate use of these medications. The second GC-MS test is to confirm illicit use of (S)-(+)-methamphetamine. In the procedure, the two methamphetamine isomers are changed to the chromatographically separable diastereomers by a chiral derivatizing agent, (S)-(-)-trifluoroacetylprolyl chloride (TPC). But the method has inherent limitations. Racemization of the reagent produces mixed diastereomers even from pure (S)-(+)-methamphetamine. Instead of using TPC, we utilized (R)-(-)-alpha-methoxy-alpha-(trifluoromethyl)phenylacetyl chloride (MTPA) to prepare the amides of diastereomers of methamphetamine. No racemization was observed with this reagent. The method was extended to resolve GC peaks of (R)-(-)- and (S)-(+)-isomers of amphetamine, 3,4-methylenedioxyamphetamine (MDA), N-methyl-MDA (MDMA), and N-ethyl-MDA (MDEA). Three ions from the drug and two ions from the deuterated internal standard were monitored to characterize and quantitate the drugs. For MDEA, only one ion was used. The quantitation was linear over 25 to 5000 ng/mL for MDEA and 25 to 10,000 ng/mL for all other drugs. Correlation coefficients were > 0.996. Precision calculated as the coefficient of variation at the calibrator concentration of 500 ng/mL was within +/- 11% for all drugs. The method was applied to test 43 urine specimens. In 91% of the methamphetamine-positive specimens, only the (S)-(+)-isomer was detected. In all MDMA-positive specimens, the concentrations of (R)-(-)-isomer were greater than the (S)-(+)-isomer indicating longer retention of (R)-(-)-isomer in the human body. The specimen concentrations (R + S) compared well with that of a non-chiral method that used 4-carboethoxyhexafluorobutyryl chloride as derivatizing agent. But the MTPA method has some advantage. It alone can replace the two GC-MS methods needed to confirm the presence of (S)-(+)-isomers of amphetamine and methamphetamine.

Comparison of the Microgenics CEDIA heroin metabolite (6-AM) and the Roche Abuscreen ONLINE opiate immunoassays for the detection of heroin use in forensic urine samples.

Current Department of Defense (DoD) and Department of Health and Human Services (HHS) procedures for the detection of heroin abuse by testing urine utilize an initial opiate (codeine/morphine) immunoassay (IA) screen followed by gas chromatography-mass spectrometry (GC-MS) confirmation of 6-acetylmorphine (6-AM), if the morphine concentration is above established cutoff. An alternative to the current opiates screen for heroin abuse is the direct IA for the metabolite of heroin, 6-acetylmorphine. In this regard, the performance of the Microgenics CEDIA heroin metabolite (6-AM) screening reagent was assessed. This evaluation was conducted on the P module of a Hitachi Modular automated IA analyzer calibrated using 6-AM at 10 ng/mL. Reproducibility, linearity, accuracy, sensitivity, and interferences associated with use of the 6-AM IA reagent were evaluated. The IA reagent precision (percent coefficient of variation (%CV)) around each of seven standards was less than 0.63%, with a linearity (r(2)) value of 0.9951. A total of 37,713 active duty service members' urine samples were analyzed simultaneously using the CEDIA heroin metabolite (6-AM) reagent and the Roche Abuscreen ONLINE opiate reagent to evaluate both the prevalence rate of 6-AM in the demographic group and the sensitivity and specificity of the reagents for the detection of heroin use. Of the 37,713 samples tested using the CEDIA heroin metabolite (6-AM) reagent, three samples screened positive at the DoD and HHS cutoff of 10 ng/mL. One of the three samples confirmed positive for 6-AM by GC-MS above the cutoff of 10 ng/mL, the two remaining samples confirmed negative for 6-AM at a GC-MS limit of detection (LOD) of 2.1 ng/mL. In contrast, the Roche Abuscreen ONLINE opiate IA produced 74 opiate-positive results for codeine/morphine, with 6 of the 74 specimens confirming positive for morphine above the DoD cutoff concentration of 4000 ng/mL (8% DoD morphine confirmation rate), only one of the 74 opiate-positive screen specimens confirmed positive for 6-AM above the 10 ng/mL GC-MS cutoff concentration. As a further check of the sensitivity and specificity of the Microgenics 6-AM IA reagent, human urine samples (n = 87) known to contain 6-AM by GC-MS, were re-analyzed using both IA reagents. All 87 of the samples screened positive using the CEDIA heroin metabolite (6-AM) assay. However, using the Roche ONLINE opiate reagent, 12 of the known 6-AM positives screened negative at the DoD and HHS screening cutoff of 2000 ng/mL (morphine). Of the remaining 75 samples that screened positive by the ONLINE opiate reagent, five of the samples did not contain morphine above the DoD GC-MS cutoff concentration of 4000 ng/mL and would not have required 6-AM analysis. However, under the HHS GC-MS morphine cutoff concentration of 2000 ng/mL all 75 samples would have required 6-AM analysis. Furthermore, using the current DoD opiate screen, 17 out of 87 samples known to contain 6-AM would have gone undetected (19.5% false-negative rate); additionally, even under the more stringent HHS opiate screening standards 12 out of the 87 samples known to contain 6-AM would also have gone undetected (13.8% false-negative rate). The Microgenics CEDIA heroin metabolite (6-AM) reagent assay appears well adapted for the rapid and specific detection of heroin abuse as an alternative for, or an adjunct test to, the current opiates (codeine/morphine) IA screening procedure.