Arthur J. McBay

Cannabis: pharmacology and interpretation of effects

A selective introductory review of the Cannabis literature is presented. Subjects reviewed include the relative psychoactivities of Cannabis constituents, the disposition and distribution of THC and its metabolites, the relative psychoactivities of THC metabolites, and the use of cannabinoid concentrations in physiological fluids in interpretations of the significance of Cannabis-induced effects. The pharmacology of cannabinoids in humans is emphasized.

Isopropanol and Isopropanol Deaths—Ten Years' Experience

A population of persons who were found, at death, to have significant levels of isopropyl alcohol (isopropanol) in their blood is described. The role of isopropanol in causing death is reviewed in 57 fatal cases. The contribution of acetone, the major metabolite of isopropanol, to death is assessed. Results indicate that mixed alcohol poisoning with ethanol and isopropanol suggests decreased production of acetone. Modalities for antemortem and postmortem detection of isopropanol are presented.

Determination of Propoxyphene in Biological Materials

Propoxyphene is 4-dimethylamino-3-methyl-1, 2-diphenyl-2-butanol propionate. The dextrorotatory salt is a very popular prescription analgesic marketed as Darvon®. The levorotatory product, which is not especially popular as an antitussive, is marketed as Novrad®. Dextropropoxyphene hydrochloride is very soluble in water (2 g/ml) and is marketed in capsules by itself and together with acetylsalicylic acid, phenacetin, caffeine, and also a tranquilizer. The capsules usually contain 32 or 65 mg of dextropropoxyphene hydrochloride. Unfortunately, the ready solubility of the hydrochloride has allowed for easy abuse of this drug by injection. A capsule which contained the drug in a spherical tablet also allowed the easy separation of this drug from other ingredients. This form has been discontinued. In an effort to prevent the misuse of the drug and to increase its safety, the manufacturer has produced a water-insoluble salt (1.5 mg/ml), propoxyphene napsylate, or the 2-naphthalene sulfonate which is marketed as Darvon-N®. Because of the weight of the salt this product is supplied in 50- and 100-mg dosage forms as tablets and a suspension containing 50 mg of Darvon-N® per 5 ml. The tablets are film-coated. The insolubility of this product should restrict its abuse and might prevent deaths by allowing for a much slower absorption of the drug.

Drug Involvement in Automobile Driver and Pedestrian Fatalities

This is the first of a 3 year study dealing with the incidence of drugs occurring in single and multiple automobile crashes in which the operator or a pedestrian was fatally injured. The operator or pedestrian must be 15 or older, have died at the crash scene or been dead on arrival at a hospital. A blood, liver and urine specimen were required, the latter only when available. Tissue specimens from 67 vehicle operators and 33 pedestrians were examined for the presence of drugs and carbon monoxide. Liver sections were examined microscopically. Single automobile crashes: Of 39 operators, 61% had alcohol involvement and alcohol plus another drug in 51%. Microscopic examinations of the livers of 24 of these victims were performed. Fourteen showed changes indicative of chronic alcohol abuse. MULTIPLE automobile crashes: Of 28 fatally injured drivers, 25% showed incidence of alcohol involvement. A drug was detected in the urine of 2 of the victims. PEDESTRIANS: 54% of 33 pedestrian fatalities involved alcohol, drugs alone were detected in 15%, and combination of the two in 6%. Thus far the study revealed alcohol as the major drug detected in operators. Alcohol involvement in pedestrians represented 72% of the total positive drug cases. Drugs other than alcohol were in 20% and drugs and alcohol in 8% of the cases. The data indicates a gross overrepresentation of alcoholics among operator crash and pedestrian crash victim populations. /MW/

THE USE OF MARIHUANA, ETHANOL, AND OTHER DRUGS AMONG DRIVERS KILLED IN SINGLE-VEHICLE CRASHES

Marihuana, ethanol, and other drugs are considered by many to be detrimental to the safe operation of motor vehicles. However, direct epidemiological evidence for this belief exists only for ethanol. The goal of this investigation was to determine the incidence of the psychoactive ingredient of marihuana, Δ9-tetrahydrocannabinol (THC), along with ethanol and other drugs in blood specimens from a carefully defined population of dead drivers. Although THC and other drugs were present in a small number of the blood specimens, the large number of specimens that had high blood ethanol concentrations indicated that alcohol is still the major drug affecting highway safety.

Fatal verapamil poisoning.

A case of fatal verapamil poisoning is reported. The pathologic and toxicologic findings are discussed.

Cost-Effective Drug Testing

Drug testing of employees has become very popular. It has been stated that such testing is necessary because of the widespread use of drugs that affect the health, safety, and performance of workers. The sudden increase in demand for such testing has led to inadequate testing and questionable interpretation of results. High quality testing is relatively expensive. A method for evaluating the effect of drug testing programs is sorely needed. Even more important is a program for evaluating the quality of testing and the competency of those who interpret the tests. There is practically no documentation of the past and present extent of the drug problem in the workplace.

Tragedy at Gunpowder River: Amtrak-Conrail Collision, Chase, Maryland

The National Transportation Safety Board (NTSB) reported that the collision between an Amtrak train and three Conrail locomotives on 4 Jan. 1987 was caused by impairment of the engineer of the Conrail locomotives from marijuana and by the failure of and lack of safety devices. Evaluation of NTSBs report does not support marijuana impairment as a cause of the accident, but it does reveal many safety problems.

Forensic Science Identification of Drugs of Abuse

The guidelines for forensic urine drug testing do not specify the gas chromatographic/mass spectrometric (GC/MS) procedure to be used for confirmation. Full mass spectral documentation together with a positive immunoassay and supporting data should insure the most certain identification. Preparation of specimens which test proficiency adequately is difficult, particularly for marijuana testing. The use of a full-spectrum GC/MS method should make the results admissible under the Frye Standard and the Federal Rules of Evidence, whereas ion monitoring methods could be challenged effectively. Duplicate specimens should be available, one for employer and the other for the employee. Precision suffers when determining low substance concentrations.

A Review of Poison Detection in Human Organs

This is the third edition of an excellent textbook on analytical toxicology. Those of us who have used the first edition (1963), 150 pages, and the second edition (1969), 280 pages, will be pleased with this enlarged and revised edition. About half the book is devoted to general toxicological information including emergency hospital toxicology, drug abuse screening, and analysis of blood, urine, liver, gastric content, brain, and kidney. The last half of the book is devoted to monographs on the analysis of specific substances. There are over 500 references; most are very recent. Of particular value are the interpretations of results.