[Download] "In Vitro Contamination of Hair by Marijuana Smoke (Drug Monitoring and Toxicology)" by Clinical Chemistry # Book PDF Kindle ePub Free
eBook details
- Title: In Vitro Contamination of Hair by Marijuana Smoke (Drug Monitoring and Toxicology)
- Author : Clinical Chemistry
- Release Date : January 01, 2004
- Genre: Chemistry,Books,Science & Nature,
- Pages : * pages
- Size : 200 KB
Description
Hair analysis has shown great potential in the detection and control of drug use (1-5) because drugs become entrapped during hair fiber formation and stabilized in the keratin matrix. The accurate interpretation of analytical results continues to be difficult because many questions concerning drug incorporation into hair remain unanswered. This applies particularly to cannabinoid findings in hair. Incorporation of cannabinoids into hair is weak compared with basic substances such as cocaine or methylenedioxymethamphetamine (6-8). The concentration of [[DELTA].sup.9]-tetrahydrocannabinol (THC) [3] that can be detected in hair after active drug use is typically far less than 5 [micro]g THC/g of hair (7). The analysis of hair to identify cannabis use is often restricted to the identification of THC, because 11-nor-9-carboxy-[[DELTA].sup.9]-THC concentrations, reported to be 0.1 [micro]g/g of hair, cannot be determined by routine gas chromatography-mass spectrometry (GC/ MS) procedures (9,10). Consequently, for cannabinoids, the use of the metabolite-to-parent drug ratio, proposed to differentiate active use from passive exposure, cannot be applied to routine cases (11,12). Although detectable amounts of THC in the blood of nonsmokers have been demonstrated after exposure to marijuana smoke, the low concentrations in blood in these circumstances make it unlikely that the amounts of THC in hair would be measurable (13). In addition to inhalation of smoke, the deposition of a drug on/into the keratin matrix of hair from the environment has been proposed as a further source of drug findings in hair. Romano and coworkers (14,15) showed that manual contamination with powdered cocaine or heroin hydrochloride and hashish or marijuana produced positive drug findings and that decontamination procedures were not sufficient to remove drugs that had penetrated into hair fibers. Several authors (16-18) have investigated the deposition of cocaine from the vapor produced by crack smoking, but similar results for cannabis are not yet available.