SOUTHWESTERN ASSOCIATION OF TOXICOLOGISTS

2001 FALL MEETING

NOVEMBER 1-3, 2001

SAN ANTONIO, TEXAS

The Alamo in San Antonio, Texas

The Fall 2001 meeting of the Southwestern Association of Toxicologists was held November 1-3 at the Menger Hotel in San Antonio. A special topic was "Revisiting the Genene Jones Case - 20 Years" with Rod McCutcheon, Jim Garriott, and Ronald Sutton (U.S. Attorney for the 198th District). Workshops presented included

Abstracts

Preliminary Investigation Into Identification and Quantitation of 2,5-Dimethoxy-n-PropylthioPhenethylamine a.k.a. 2C-T-7

Byron Curtis, B.S.1, Linda Harty, B.S.1, Phil Kemp, Ph.D. 1,Chai Choi M.D.1, Gary Sneed, B.S. 1, and Dix Christensen2
1Office of the Chief Medical Examiner, State of Oklahoma, 1901 N. Stonewall, Oklahoma City, OK 73117
2 College of Pharmacy, OUHSC

2,5-Dimethoxy-4-n-propylthiophenethylamine the drug commonly known as 2C-T-7, has been sold on the street under the names "Blue Mystic" and "Tweetybird Mescaline". 2C-T-7, a phenethylamine derivative presumably first synthesized in 1986 has structural and pharmacodynamic properties similar to the drugs Mescaline, MDMA, and Paramethoxyamphetamine. In October 2000 a 20-year-old white male presented to the emergency room in full arrest with an account of sudden seizures. Initially gamma-hydroxybutyrate involvement was suspected. Some months later information was provided that reported the use of 2C-T-7 shortly before the incident. Other information also obtained later from witnesses described the decedent as experiencing hallucinations and feeling cold within 20 minutes of insufflating about 35mg of 2C-T-7. After ninety minutes the decedent began having convulsions, vomiting, and bleeding from the nose. Subsequently the decedent stopped breathing during the ride to the hospital and arrived at the emergency room in cardiac arrest. Autopsy results were unremarkable with the exception of pulmonary edema and recent minor abrasions/contusions that were suggestive of convulsions. Routine toxicology screening indicated an unidentified substance in urine that was later identified as 2,5-Dimethoxy-4-n-propylthiophenethylamine using material provided by the Drug Enforcement Administration.

Screening was performed using liquid/liquid extraction with split dual column injection on an HP-5890 (GC) with Nitrogen-Phosphorus detectors (NPD). Confirmation was accomplished with an HP-6890GC/HP-5973 MSD. Quantitation was attempted on an HP-5890 (GC-NPD). Preliminary data are as follows: heart blood 54 ng/ml, femoral blood 100ng/ml, vitreous < 26 ng/ml, brain 340 ng/g, urine 440 ng/ml. This presentation will discuss data obtained thus far, analytical issues, and future efforts to characterize this compound.

Application of Drug Identification in Hair, Saliva, Sweat, Meconium, and Fingernails

Ashraf Mozayani, PharmD., Ph.D. D-ABFT
Harris County Medical Examiners Office, 1885 Old Spanish Trail Houston, TX 77054
ashraf_mozayani@meo.co.harris.tx.us

The most common biological specimens for testing drugs and their metabolites in forensic cases are blood and urine. However, with recent advances in extraction technology and instrumentation it has become more practical to explore unconventional biological matrices such as saliva, sweat, fingernails, meconium, and hair. Like any other scientific procedure, the testing of these matrices can be appropriate in some instances and inappropriate in other instances. This presentation is a general review to offer a balanced view of the pros and cons of drug testing in these unconventional matrices.

Clinical Testing for Toxic Exposures

John Tarver, Technical Director
AccuChem Laboratories, 990 N. Bowser Rd., Suite 800, Richardson, TX 75081
jtarver@accuchemlabs.com

This is an aspect of toxicology that most of us are not involved in or familiar with. The purpose of this presentation is:

The Effects of Consumption of Herbal Dietary Supplements on Amphetamine/Methamphetamine Urinalysis

Brigid Mahula, M.S. and Gary W. Kunsman, Ph.D.
Forensic Toxicology Laboratory, Bexar County Medical Examiner's Office, San Antonio, Texas

The use of herbal supplements marketed as natural stimulants continues to increase in popularity. Secondarily, the use of the defense that administration of such products is the cause of a positive amphetamines urinalysis result has also been noted. A study was conducted to evaluate the potential for false positive results on 4 amphetamine/methamphetamine immunoassays by testing urine collected from 8 subjects taking three popular herbal products (Metabolife 356®, Diet Phen™, and ECA Stack™) on a fixed administration and urine collection schedule. A total of 268 urine specimens were collected and screened using the Abbott AxSYM® (FPIA), Roche ONLINE (KIMS), and the STC Technologies Micro-Plate (EIA) immunoassays. All urine samples were also analyzed for the presence of amphetamine, methamphetamine, ephedrine, and pseudoephedrine using a gas chromatography/mass spectrometry (GC/MS) method. No pattern of immunoassay positive results was noted in relation to dose or duration of use of the herbal products and only the EIA methamphetamine assay exhibited a large number of positive results. GC/MS analysis of the urine samples revealed no amphetamine-related compounds except for ephedrine and pseudophedrine in those specimens collected when subjects were taking an ephedra-containing product. No relationship could be established between the ephedrine and/or pseudoephedrine concentrations and the positive immunoassay results. In conclusion, the use of an 'herbal supplement defense' to account for a positive amphetamine/methamphetamine urinalysis result has been negated by this study.

Identification of Cinnarizine in Postmortem Specimens

Michael Frontz, MSFS and Gary W. Kunsman, Ph.D.
Forensic Toxicology Laboratory, Bexar County Medical Examiner's Office, 7337 Louis Pasteur, San Antonio, TX, 78229

The identification of cinnarizine (Stugeron ®), an antihistamine not currently approved for use in the U.S., was confirmed in the postmortem biological samples of an accident victim from South Texas. This is the first case submitted to the Bexar County Medical Examiner's Office in which this antihistamine has been identified. Cinnarizine, first synthesized and patented in 1959, is an H1 antagonist, and has a piperazine structure similar to hydroxyzine. The decedent was involved in a single vehicle, high-speed rollover accident in which a tire blow out was suspected as the contributing factor. The cause of death was listed as multiple injuries and the manner of death was accidental. Toxicology results included an incidental finding of cinnarizine at a level of 0.57 mg/L in femoral blood. This is higher than previously reported peak plasma levels resulting from therapeutic dosage. A cinnarizine standard was obtained and spiked bovine blood levels were linear within the range 0.05-10 mg/L. Confirmation of cinnarizine was achieved by comparing the fragmentation pattern of the standard to that identified in the following postmortem specimens at the indicated concentrations based on a linear regression analysis using the spiked negative control bovine blood calibrators: femoral blood – 0.57 mg/L, heart blood – 0.06 mg/L, bile – 0.55 mg/L, muscle – 0.26 mg/Kg, liver – 0.78 mg/Kg, and kidney – 0.18 mg/Kg.

The Use Of LC/MS In Toxicology With The Determination of Gabapentin In Serum as an Example

Paul Zavitsanos
Agilent Technologies, Little Falls, DE

The fundamentals of LC/MS that are relevant to Toxicology will be discussed. LC/API/MS has revolutionized small molecule drug analysis in the past ten years. The advantages of HPLC as a chromatographic technique is combined with an ionization technique (Atmospheric Pressure Ionization) that most often gives intense protonated molecular ions. Volatility of compounds is not required for sensitive detection; therefore derivatization schemes are rarely required. The technique has great capacity for dirty samples without failure or reduced sensitivity. The characteristics of different ionization modes as well as the impact of source design on the ruggedness of the operation will be examined. Atmospheric Pressure Chemical Ionization (APCI) and Electro-Spray Ionization (ESI) modes and sources will be fully explored. APCI is used for neutral compounds such as steroids whereas ESI is used with compounds that can be ionized in solution such as alkaloids and amine based drugs. The different aspects of LC/MS systems design will be discussed as well as a review of the spectrometer advances that have greatly increased the reliability of LC/MS over the past ten years to fifteen years.

The determination of Gabapentin in serum will be used to highlight the differences between GC and LC/API/MS in the forensic and toxicology environment.

The Ideal Circumstances and Current State of Practical Necrokinetics

Wm A. Watson, PharmD.
The South Texas Poison Center, University of Texas Health Science Center at San Antonio, San Antonio, TX

Necrokinetics describes the changes in drug concentrations that occur between the time of death and the collection of the autopsy sample. In order to define the variables involved with necrokinetics and concentration interpretation, understanding the ideal circumstance with a description of antemortem drug dosing, the pharmacological effects and the potential for tolerance is important. One of the most clearly identified practical issues is the method and site of sample collection. Peripheral venous sites are used in clinical settings and provide the best data regarding blood concentration – effect relationships. Ideally, different drug characteristics would predict whether or not necrokinetic changes would occur. There are data suggesting that a drug's antemortem volume of distribution may be useful in predicting whether postmortem change occurs. A volume of distribution greater than 2 to 3 liters per kilogram of body weight suggests that there will be significant postmortem increase. It has also been demonstrated that drug concentrations will increase more when antemortem concentrations are therapeutic.

Reference Materials and Stock Solution Quality Control

Joe L. Castorena, M.S. and Gary W. Kunsman, Ph.D.
Forensic Toxicology Laboratory, Bexar County Medical Examiner's Office, San Antonio, TX 78229

Forensic toxicologists may be confronted with a number of possible problems in the performance of quantitative analysis. Issues pertaining to specimen quality, analytical instrumentation, and procedural problems are but a few of the potential sources of error that may affect the ultimate outcome of a quantitative analysis. Problems of significant concern are associated with the reference materials used in both qualitative and quantitative analysis and the stock solutions derived from these reference materials. Such issues are particularly problematic in methods for which no commercial control(s) for the analyte(s) of interest are commercially available as the possibility of introducing systematic error into the final quantitative calculations is more difficult to evaluate and control as compared to those methods for which a commercial control is available. This presentation will address these issues and will offer solutions to these problems by proposing a model quality assurance/quality control program that may be readily employed in any forensic toxicology laboratory.

Key Words: Quality Control, Reference Materials, Stock Solutions, Ultraviolet Spectrophotometry

Tissue Distribution of Temazepam in a Fatal Overdose

Gary W. Kunsman, Ph.D., Michael E. Frontz, MSFS, and Robert C. Bux, M.D.
Forensic Toxicology Laboratory, Bexar County Medical Examiner's Office, San Antonio, TX 78229

A case is reported in which a lethal level of temazepam and asphyxia by a plastic bag were determined to be the cause of death. The decedent was a 43 year old female found in the cargo area of her sport utility vehicle parked at a nearby grocery store. Significant findings included a plastic grocery bag over her head, with the handles loosely tied around her head; acute, passive congestion of the liver, kidneys, and lungs; multiple notes detailing her intent to commit suicide were found in the vehicle; and an elevated temazepam concentration was detected in postmortem blood. The decedent had a history of depression and had attempted suicide on four previous occasions using her medications. Temazepam was identified and quantitated in the following tissues: heart blood – 7.8 mg/L, urine – 4.2 mg/L, muscle – 5.9 mg/Kg, liver - 15.5 mg/Kg, kidney – 11.3 mg/Kg, and brain – 7.5 mg/Kg. Methylphenidate was also detected in the urine (0.14 mg/L) and at trace levels in the heart blood and all submitted tissue specimens.

Open Air Carbon Monoxide Poisoning during Recreational Boating at Lake Travis

Brad J. Hall Ph.D.*, J. Rod McCutcheon B.S., Patricia Schroeder, Elizabeth Peacock M.D.
Travis County Office of the Medical Examiner, P.O. Box 1748, Austin, Texas
*presenting author
email: brad.hall@co.travis.tx.us

Carbon monoxide (CO) poisoning among recreational boaters has been recognized as a serious hazard. In a previous report, poisonings were typically associated with individuals in the cabin of the boat and exposure was from inhalation of CO from engine exhaust (1). The patients reported symptoms including headache, nausea, weakness, and dizziness and while many lost consciousness, they were all treated and recovered. Although the majority of CO poisonings occur in enclosed areas, recently several accounts of open-air CO poisonings resulting in death have been reported (2 - 3). On August 2, 2000 two young brothers were overcome by CO and subsequently drowned while swimming near the stern of a houseboat with the engine running on Lake Powell – Arizona and Utah (3). As a result of these deaths, an investigation was initiated and it has been estimated that at least nine deaths and 102 injuries have occurred on Lake Powell in the past decade. Previous measurements of CO in the air just above the water level near the stern of the boat indicate concentrations over 100 ppm (2). In the cavity beneath the stern deck on houseboats, highly lethal levels from 6,000 – 30,000 ppm have been measured (3).

The primary subject of this presentation recounts a similar case of open-air CO poisoning occurring on Lake Travis near Austin, Texas in June 2001, resulting in the death of a 28 year old Caucasian female. Law enforcement reported that the decedent and friends were anchored in a cove with several boats. It was known that alcoholic beverages were being consumed by both the decedent and friends. Witnesses state that the decedent was in the water with her arms propped on the swim platform as the boat's engine was running. Within minutes friends noticed that the decedent was missing. The body was recovered by a dive team approximately five hours from the time of the incident. Autopsy findings note fixed posterior lividity of a red color indicative of possible CO exposure. In addition, wet pulmonary parenchyma and sand in airways was noted. Otherwise pathology was unremarkable. Toxicological analysis by gas chromatography determined that CO was present in the heart blood at 53 % of saturation. Ethanol was found at the following concentrations (g/100 mL): heart blood (0.12), vitreous humor (0.12), urine (0.16), and bile (0.16). In addition, methylenedioxymethamphetamine (MDMA) and methylenedioxyamphetamine (MDA) were found in the heart blood at 0.14 and <0.05 mg/L, respectively. MDMA and MDA were confirmed in the urine by an alkaline drug screen and gas chromatography/mass spectrometry. Cause of death was ruled as fresh water drowning, with the carbon monoxide toxicity and alcohol intoxication contributing to this fact. The manner of death was ruled accidental.

In conclusion, cases involving deaths on or near a boat should be investigated for the potential involvement of CO. Based on previous studies and this report CO may accumulate to toxic levels even in what appears to be an open-air environment.

References:
1 Silvers SM, Hampson NB. Carbon monoxide poisoning among recreational boaters. JAMA 1995;274:1614-6
2 Jumbelic MI. Open air carbon monoxide poisoning. J. Forensic Sci. 1998;43:228-30
3 Baron RL, Radtke T. Houseboat-Associated Carbon Monoxide Poisonings on Lake Powell-Arizona and Utah, 2000. Morbitity and Mortality Weekly Report. 2000;49:1105-1108

Meetings

Home