Cannabis residue

Meanwhile, the indica species of the plant spread gradually from the Far East to Egypt and Persia. Schultes and Flofmann cite a "questionable specimen of Flemp in an Egyptian tomb dating as far back as three or four thousand years ago. Arab traders brought Cannabis to the Mozambique coast of Africa around the thirteenth century. From there, its use spread rapidly inland to virtually all African tribes. Archeological evidence of this transmission includes fourteenth-century waterpipes containing Cannabis residue. 

Parker LA, Gillies T THC-induced place and taste aversions in Lewis and Sprague-Dawley rats. Behav Neurosci 109 71-78, 1995 Pope HG, Yurgelun-Todd D The residual cognitive effects of heavy marijuana use in college students. JAMA 275 521-327, 1996 Robson P Therapeutic aspects of cannabis and cannabinoids. BrJ Psychiatry 178 107-115, 2001... 

Pope HG (2002). Cannabis, cognition and residual confounding. Journal of the American Medical Association, 287, 1172-1175. 

Pope HG, Gruber AJ and Yurgelun-Todd D (1995). The residual neuropsychological effects of cannabis The current status of research. Drug and Alcohol Dependence, 38, 25-34. 

Illicit drug consumption in the areas served by the investigated WWTPs was back-calculated from the drug residues found in the influent wastewaters. In the light of the results obtained, cocaine is the most abused drug, followed by cannabis, amphetamine, heroin, MDMA, and methamphetamine. This profile slightly differs from national official estimates. Deviations may result from a different drug consumption pattern in the studied area compared to the Spanish territory, or from potential biases in the approach used in this study or in official estimates. 

Gas chromatography coupled to tandem mass spectrometry (GC-MS/MS [49]) prior to analysis of the three primary active components of cannabis (THC, cannabidiol and cannabinol) by this technique, airborne particulates were extracted in an ultrasonic bath with chloroform. The extracts were combined and concentrated under a stream of nitrogen. The residue was filtered through pre-washed disposable PTFE membranes, dried and finally reconstituted with cyclohexane. After separation and solvent partitioning, the extracts were analysed by GC-MS/MS. 

Grant, L, R. Gonzalez, C. L. Garey, L. Natarajan, and T. Wolfson. Non-acute (residual) neurocognitive effects of cannabis use a meta-analytic study. J Int Neuropsychol Soc 2003 9(5) 679-689. 

CS453 Pope, H. G. Jr., A. Jacobs, J. P. Mialet, D. Yurgelun-Todd, and S. Gruber. Evidence for a sex-specific residual effect of cannabis on visuospatial memory. Psychother Psychosom 1997 66(4) 179-184. 

Finally, the cannabinoids can be extracted from the herbal material or the resin to produce hash oil. The latter is obtained from the extraction of cannabis plant material with a suitable organic solvent (for example, petrol or ether) by refluxing. Once a solution of the required strength has been obtained, the solvent is evaporated and the oil concentrated, giving a sticky green, olive or brown residue. 

Residual effects of prolonged heavy cannabis use. National Institute of Public Health and the Environment, Report No. 318902003. Bilthoven, Netherlands. 

Reprocessing of the Residue Left After Fractional Distillation of Cannabis Extracts 82% THC Yellow Oil... 

Stiglick A, Llewellyn ME, Kalant H (1984) Residual effects of prolonged cannabis treatment on shuttle-box avoidance in the rat. Psychopharmacology (Berl) 84 476-479... 

Gonzalez R, Carey C, Grant I (2002) Nonacute (residual) effects of cannabis use a qualitative analysis and systematic review. J Clin Pharmacol 42 48-578... 

In accordance with the latter two investigations, a recent meta-analytic study of residual neurocognitive effects of cannabis use did not reveal detrimental effects, except for a modest impairment in memory tests. The authors conclude that when medical use of cannabinoids is being considered, the health benefits should be carefully weighed against the very modest potential for cognitive decline (Grant et al., 2003). 

Subjects should not be discharged from a cannabis-administration research study until they have been evaluated for any unresolved or residual adverse effects from study participation. Adverse physical and psychological effects from acute cannabis administration, such as tachycardia, orthostatic hypotension, impaired motor coordination, and drowsiness, usually resolve completely within hours. Thus, subjects can usually be safely discharged a few hours to a... 

The decision to use paraquat on Cannabis to control illegal marihuana production in the United States and Mexico provides another route of human exposure. This exposure results from residues accumulated at harvest, immediately after, and at subsequent times, following a spray application. This occurs when the grower attempts to salvage treated Cannabis plants after an authorized spray operation is conducted to destroy the crop. The herbicide s rapid desiccation renders the treated Cannabis unusable as a harvestable... 

The objective of the present experiment was to estimate the possible transfer of paraquat residues from Cannabis and soil to humans engaged in harvesting treated plants. Residues on gloves and plastic boots were used as surrogates to measure transfer from treated plants and soil. No human exposure occurred in these experiments since the harvesters were completely covered with protective clothing. 

After 8 h the treated Cannabis plants showed signs of substantial desiccation and browning, which probably further reduced the transfer of paraquat to the gloves of harvesters. The cumulative residues for both hands after 0, 1, 2, 4, 8, and 29 h was 1.45, 2.42, 3.07, 3.60, 4.01, and 4.24 mg, respectively. These cumulative residues would appear to be higher than those reported by Forbess et al. (1) on hands of either sprayer (0.081-1.324 mg) or mixers (nd-0.231 mg) engaged in paraquat applications to grape vineyards. 

---