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At a recent South Australian rave, results reported to users from on-site pill-testing, using pill-testing kits, were compared with GCMS analysis of a scraping from the same pill. The presence of an ecstasy-like substance or methylamphetamine was correctly reported to users in 100% of pills that contained those substances. However only 11% of pills with combinations of illicit substances had both substances correctly identified. Ketamine was particularly problematic with identification occurring in only 18% of pills and in some instances, the colorimetric response obtained from ketamine was confused with the response from methylamphetamine. This study also allowed a comparison between pill design and composition encountered at the rave with those submitted to the forensic laboratory over a 6-month period including the month the rave was held. MDMA was present in 68% of pills at the rave and 89% of pills submitted by the police. Ketamine was present in 27 and 26% of pills, respectively and was often combined with other substances. The combinations of illicit substances were identical apart from one police-pill seizure that contained MDMA combined with PMA. This combination has not been previously encountered in South Australia. The pill designs observed at the rave differed significantly from the designs on pills submitted for testing by police. These differences limit the use of pill comparison charts as an alternative identification tool to colorimetric pill testing in South Australia.  相似文献   
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The common history of drug abuse in adults with an undetermined cause of death has led us to hypothesize that chronic drug abuse increases the risk of sudden death. To begin evaluating this hypothesis, we conducted a retrospective case-control study of 61 decedents whose cause of death remained undetermined following autopsy matched one to one to a control group of pedestrians or passengers killed in motor vehicle collisions. In 21 pairs, the case subject had evidence of drug abuse but the control did not, and in 5 cases the reverse was true. Analysis showed that individuals with an undetermined cause of death are 4.2 times more likely to have evidence of drug abuse than are victims of a motor vehicle collision.  相似文献   
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