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81.
Methamphetamine is the most commonly seized amphetamine-type stimulant (ATS) worldwide. Chemical residues associated with the use or manufacture of methamphetamine can persist in the air and surfaces in a property for over 5 years and potentially pose risks to the health and safety of the public. When a house is tested for contamination, the test focuses on the presence of surface methamphetamine residue; however, other hazardous chemicals may also be present, including methamphetamine precursors and reaction products. As little has been reported about the ageing of the methamphetamine inside dwellings, there is currently large uncertainty regarding its fate and/or degradation products in such environments. If the indoor reactivity of methamphetamine is similar to that of nicotine-derived third-hand smoke, the production of a carcinogenic nitrosamine is an expected result. Thus, this proof-of-concept study investigated the reaction of methamphetamine with the common gaseous indoor oxidant nitrous acid (HONO) and monitored the fate of the resulting reaction products in simulated laboratory experiments to further understand the potential health risks associated with contaminated properties. Surface methamphetamine residue was observed to decrease with an exponential decay with an upper limit of 2.38 ± 0.5 × 10−3 min−1 upon exposure to HONO gas (5.7 ppmv, 0.25 L min−1). N-nitrosomethamphetamine (NMA), a suspected human mutagen and carcinogen, was detected to have a steady-state formation over the sampling time frame, with a surface area concentration of 0.87 μg/100 cm2, suggesting that the risks to public health for properties contaminated with methamphetamine may be currently underestimated. 相似文献
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《Drug testing and analysis》2017,9(4):603-612
Third‐hand smoke is the residue remaining on surfaces during smoking events. It is composed of particles and vapours that form upon heating. The phrase ‘third‐hand smoke’ is primarily used to describe nicotine and other chemicals from cigarettes, but any residues formed from the smoking of various substances could be classified similarly. There has been an increasing body of research on third‐hand smoke from cigarettes in the last decade, but little has been done in regards to understanding the persistence of particles and vapours from illicit drugs. In this work, small samples of cocaine and methamphetamine were volatilized to produce an illicit drug smoke that was collected onto various surface materials and left exposed to ambient conditions over 672 h (four weeks). Chemical analyses by electrospray ionization‐mass spectrometry of residues on silicon, plastic, laminate, and artificial leather surfaces indicated a rapid decrease in recovery of the parent molecule, with varied formation of decomposition products over the first 168 h of exposure. Measurable amounts of the parent molecule were still present after 672 h, exhibiting a strong persistence of these drugs on various household materials. This is important in a forensic science context, as third‐hand smoke residues could provide a viable source of trace evidence previously not utilized. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
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Alia Al-Tayyib Stephen Koester Sig Langegger Lisa Raville 《Substance use & misuse》2017,52(8):1051-1058
Objective: We sought to describe an emerging drug use pattern characterized by injection of both methamphetamine and heroin. We examined differences in drug injection patterns by demographics, injection behaviors, HIV and HCV status, and overdose. Methods: Persons who inject drugs (PWID) were recruited as part of the National HIV Behavioral Surveillance (NHBS) system in Denver, Colorado. We used chi-square statistics to assess differences between those who reported only heroin injection, only methamphetamine injection, and combined heroin and methamphetamine injection. We used generalized linear models to estimate unadjusted and adjusted prevalence ratios to describe the association between drug injection pattern and reported nonfatal overdose in 2015. We also examined changes in the drug reported as most frequently injected across previous NHBS cycles from 2005, 2009, and 2012. Results: Of 592 participants who completed the survey in 2015, 173 (29.2%) reported only injecting heroin, 123 (20.8%) reported only injecting methamphetamine, and 296 (50.0%) reported injecting both drugs during the past 12 months. Injecting both heroin and methamphetamine was associated with a 2.8 (95% confidence interval: 1.7, 4.5) fold increase in reported overdose in the past 12 months compared with only injecting heroin. The proportion of those reporting methamphetamine as the most frequently injected drug increased from 2.1% in 2005 to 29.6% in 2015 (p < 0.001). Conclusions: The rapid increase in methamphetamine injection, and the emergence of combining methamphetamine with heroin, may have serious public health implications. 相似文献