MARIJUANA-AND COCAINE-RELATED DEATH-ACCIDENTAL
The decedent was a 23-year-old employee who was riding on the front right side of a cherry picker when he fell off and was crushed by the wheels. The decedent was one and one-half hours into his shift at the time of his death which was instantaneous. At post mortem examination, 30 ml of whole blood was withdrawn from the chest cavity. Laboratory analysis by gas chromatography/mass spectroscopy revealed 43 nanograms per milliliter (ng/ml) of tetrahydrocannabinol. No metabolites were present in the sample. Cocaine was present at a concentration of 50 ng/ml. Benzoylecgonine concentration was 230 ng/ml and methylecgonine concentration of 120 ng/ml. The post mortem examination was performed approximately five and one-half hours after death. Blood specimens were preserved with fluoride.
Urine drug screens performed on the driver were positive for the metabolites of both marijuana and cocaine. Neither blood nor urine specimens collected from the driver were tested for the presence of cocaine or tetrahydrocannabinol. A marijuana cigarette butt and a small amount of a white powder identified as cocaine were present in the cab of the cherry picker.
DEFENSE POSITION: The decedent was impaired at the time of his death by marijuana and cocaine. No conclusion can be drawn concerning impairment of the driver because appropriate analyses were not performed.
DISCUSSION: The presence of tetrahydrocannabinol in the absence of any metabolites supports the use of marijuana within a few minutes of the time of death. The presence of cocaine and cocaine metabolites confirmed by a gas chromatography/mass spectroscopy supports impairment as a consequence of the use of cocaine. The case illustrates the importance of obtaining blood specimens as close to the time of an accident as possible with the specimen collected over a suitable preservative and analyzed by gas chromatography/mass spectroscopy for the presence of the active substances rather than the metabolites which have no psychogenic activity. The collection of urine specimens post accident subjected to the usual methods of analysis for marijuana or cocaine metabolites provides no information upon which a reasonable medical probability statement can be made concerning the presence of impairment at the time of the accident. Since the metabolites both of marijuana and cocaine continue to be excreted in the urine for long periods of time after disappearance of impairment, the only value of urine screens is to establish that illicit substances have been used at some time prior to the specimen collection.
DISPOSITION: After deposition testimony, a summary judgement dismissed a suit by the survivors.
Eric G. Comstock, M.A., M.D., DABMT, FACMT, FAACT, FACOEM, Expert for the defense. (7483)
Charles Seymore, Houston, Texas, Attorney for the defense.
If you have any questions please
let me know.
The full text of Dr. Comstock’s deposition testimony is available upon request. (713) 541-3214.
NOTES:
Hollister, 1981, demonstrated that plasma concentrations of delta-9-tetrahydrocannabinol correlate well with the peak “high” in human volunteers. There was no correlation between the concentration of the metabolic derivatives of tetrahydrocannabinol (THC) and psychological or pharmacologic effects. Smoking produced a peak THC concentration in serum after approximately three minutes. Scherrmann, 1981, administered 15 mg and 17 mg of THC in cigarettes and demonstrated that the concentration of THC in serum peaked at approximately 15 minutes at near 100 nanograms per milliliter (ng/ml). Using a composite measurement of skills adversely affected by marijuana, Cheshire, et al. Demonstrated decrement of performance to be maximal after approximately 30 minutes after smoking marijuana. By comparing the degree of impairment by marijuana with that of 0.05 Gm% alcohol, impairment was similar to a dose of 1 mg to 2 mg of THC. The decrement of performance disappeared in approximately three hours. Law, using human volunteers, differentially determined the concentration of THC and its metabolites after the oral administration of 20 mg of THC and demonstrated that within one hour, the concentration of total metabolites was approximately five times the concentration of THC. These observations support the conclusion that only a few minutes had elapsed from the time of use of marijuana and death of the patient in this case.
REFERENCES:
Hollister LE, Gillespie HK, Ohlsson A, et al. Do Plasma Concentrations of delta-9-Tetrahydrocannabinol Reflect the Degree of Intoxication? J Clin Pharmacol Rev 23:273-278, 1981.
Scherrmann, JM, et al. Detection of Quantitation of Cannabinoids in Biological Fluids: Specificity and Kinetics after Smoking. Clin Toxicol 18:565-571, 1981.
Chesher GB, Bird KD, Stramarcos A, Nikias N. Marihuana 84: Comparative Study of the Dose-Response Relationship of Alcohol and Cannabis on Human Skills Performance. In: Ninth International Congress of Pharmacology, 3rd Satellite Symposium on Cannabis, 1985; pp.621-627.
Law B, Moffat AC. The influence of the Metabolism and Elimination of Cannabinoids on Forensic Analysis and Interpretation. In: Ninth International Congress of Pharmacology, 3rd Satellite Symposium on Cannabis, 1985; pp. 197-204.
| Toxic Substance Litigation Register | Discovery
| E-Mail Dr. Comstock |