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91.
Danielle McCartney Richard C. Kevin Anastasia S. Suraev Christopher Irwin Ronald R. Grunstein Camilla M. Hoyos Iain S. McGregor 《Drug testing and analysis》2022,14(1):137-143
Many jurisdictions use point-of-collection (POC) oral fluid testing devices to identify driving under the influence of cannabis, indexed by the presence of Δ9-tetrahydrocannabinol (THC), an intoxicating cannabinoid, in oral fluid. Although the use of the non-intoxicating cannabinoid, cannabidiol (CBD), is not prohibited among drivers, it is unclear whether these devices can reliably distinguish between CBD and THC, which have similar chemical structures. This study determined whether orally administered CBD produces false-positive tests for THC on standard, POC oral fluid testing devices. In a randomised, double-blind, crossover design, healthy participants (n = 17) completed four treatment sessions involving the administration of either placebo or 15-, 300- or 1500-mg pure CBD in a high-fat dietary supplement. Oral fluid was sampled, and the DrugWipe®-5S (DW-5S; 10 ng·ml−1 THC cut-off) and Drug Test® 5000 (DT5000; 10 ng·mL−1 THC cut-off) devices administered, at baseline (pretreatment) and ~20-, ~145- and ~185-min posttreatment. Oral fluid cannabinoid concentrations were measured using ultra-high performance liquid chromatography–tandem mass spectrometry. Median (interquartile range [IQR]) oral fluid CBD concentrations were highest at ~20 min, quantified as 0.4 (6.0), 15.8 (41.6) and 167 (233) ng·ml−1 on the 15-, 300- and 1500-mg CBD treatments, respectively. THC, cannabinol and cannabigerol were not detected in any samples. A total of 259 DW-5S and 256 DT5000 tests were successfully completed, and no THC-positive tests were observed. Orally administered CBD does not appear to produce false-positive (or true-positive) tests for THC on the DW-5S and DT5000. The likelihood of an individual who is using a CBD (only) oral formulation being falsely accused of DUIC therefore appears low. 相似文献
92.
Priska Frei Stephanie Frauchiger Eva Scheurer Katja Mercer-Chalmers-Bender 《Drug testing and analysis》2022,14(7):1223-1233
Cannabis is the most frequently consumed illegal substance worldwide. More recently, an increasing number of legal cannabis products low in psychoactive Δ9-tetrahydrocannabinol (THC) but high in non-intoxicating cannabidiol (CBD) are being more widely consumed. While the detection and quantification of THC and its metabolites in biological matrices is an important forensic-toxicological task, additional detection of CBD is also important, for example, when examining the plausibility of consumer's statements. This report describes the method validation for the quantitative determination of THC and its two major metabolites, 11-hydroxy-THC (OH-THC) and 11-nor-9-carboxy-THC (THC-COOH), as well as CBD and cannabinol (CBN) in whole blood and urine. The method employs automated on-line solid phase extraction coupled to gas chromatography tandem mass spectrometry (GC–MS/MS). The method was fully validated according to guidelines of the Swiss Society of Legal Medicine (SGRM) and the Society of Toxicological and Forensic Chemistry (GTFCh). The method fulfilled the validation criteria regarding analytical limits, accuracy and precision, extraction efficacy, and sample stability. The limits of detection (LODs) in whole blood and urine were 0.15 ng/mL for THC, OH-THC and CBD, 0.1 ng/mL for CBN, and 1.0 ng/mL for THC-COOH. The limits of quantification (LOQ) in whole blood and urine were 0.3 ng/mL for THC, OH-THC and CBD, 0.2 ng/mL for CBN, and 3.0 ng/mL for THC-COOH. The fully validated and automated method allows sensitive and robust measurement of cannabinoids in whole blood and urine. Detection of CBD provides additional information regarding consumed products. 相似文献
93.
The barrier component and the driving force component of transepidermal water loss and their application to skin irritant tests 总被引:1,自引:0,他引:1
Koji Endo Noboru Suzuki Osamu Yoshida Hirayuki Sato Yoshiaki Fujikura 《Skin research and technology》2007,13(4):425-435
BACKGROUND/AIM: According to Fick's law of diffusion, the rate of transepidermal water loss (TEWL) is determined by a barrier component and a driving force component. The objective of this study is to propose novel indicators for the assessment of skin irritation potential from chemicals using these components. METHODS: Before and after acetone/ether (AE), sodium lauryl sulfate (SLS) and nicotinic acid methyl ester (NME) treatments, the apparent mass transfer coefficient of water, K, of the stratum corneum (SC) and the apparent water vapor pressure, P(d), at the interface between SC and epidermis were estimated as measures of the SC barrier and the driving force, respectively. RESULTS: After AE treatment, K showed marked increase and P(d) remained approximately constant. All participants reacted to NME with erythema and the laser-Doppler flowmetry (LDF) value peaked at around 30 min. While there was a change in P(d), which parallels with LDF changes, K showed little variation. Repeated SLS treatment induced a slight increase in P(d) besides an increase in K. In the meantime, all participants reacted with subtle erythema. CONCLUSIONS: Our results suggest that not only the SC barrier but also the driving force determines variations in the TEWL rates during skin irritant tests. Together, K and P(d) will provide us with invaluable information about skin condition. 相似文献
94.
95.
《Disability and rehabilitation》2013,35(4):180-181
A postal survey of 50 car drivers with restricted movement of the cervical spine revealed that many experienced difficulties when negotiating junctions or reverse parking. In many cases supplementary interior mirrors increased the drivers' field of vision, enabling them to perform manoeuvres more safely. Choice of suitable mirrors and their exact positioning depends on the design of the vehicle and the individual's disability. 相似文献
96.
97.
Jennifer Liut Ulrich Bott Burkhard Madea Michael Krämer Alexandra Maas 《Drug testing and analysis》2022,14(8):1407-1416
Driving under the influence of drugs (DUID) remains a subject of concern worldwide, and its increasing trend is likely to continue. Therefore, there is a constant need for reliable on-site drug tests to identify drugged drivers during roadside patrols. Performance and reliability of four on-site drug tests were evaluated among a high number of DUID cases in Germany. Results of oral fluid (OF) (RapidSTAT® and DrugWipe® 6S) and urine (DrugScreen® 5TK and 7TR) test devices were compared with corresponding serum/plasma results obtained by confirmation analyses in consideration of recommended analytical limits for substances pertaining the annex of the German Road Traffic Code (‘Straßenverkehrsgesetz’, StVG) s. 24a (2). Overall, the screening devices performed well for individual drugs; however, none of the test devices assessed in this study fulfilled the ROSITA-1 criteria (sensitivity, specificity ≥ 90% and accuracy ≥ 95%) for all substances. Our data demonstrated that both urine tests showed high sensitivities for most compounds. DrugWipe® 6S (94%) and RapidSTAT® (93%) revealed high sensitivities, especially for amphetamine screening. Poor specificities (<90%) and accuracies (<95%) were observed for all tests except for low-prevalent substances (e.g., opiates). For drug testing in OF, Δ9-tetrahydrocannabinol (THC) still seems to be a compound of concern due to poor sensitivity (RapidSTAT®, 77%; DrugWipe® 6S, 85%), although the results indicate improvements compared with previously reported data. Although the obtained data indicate reliable detection for some substances, deployment of trained police officers is inevitable to identify DUID suspects by signs of recent use and recognising impairment. 相似文献
98.
Accident register data, time budget studies and road traffic flow data were used to compute the age and gender-dependent relative risk [odds ratio (OR)] of being involved in a driving accident in which the driver was injured or killed. Alcohol-related accidents were excluded from the analysis. The results showed that the night-time risk, compared with that of the forenoon, was dramatically increased (OR=5) for young drivers (18--24 years) and reduced for old (65+) drivers. In direct comparison, the young drivers had 5-10 times higher risk of being involved in an accident during late night than during the forenoon, with the excess risk during the daytime being considerably lower. Women had a less pronounced night-time peak than men. In direct comparison, men had twice as high a risk as women during the late night hours. The results clearly demonstrate a strong effect of young age on night-time accident risk, together with a moderate effect of (male) gender. 相似文献
99.
作者运用描述流行病学方法分析了南京铁路分局1953~1989年发生行车事故的时间分布特征。主要结论如下:37年间行车事故发生有两次高峰期,分别是1958~1962年和1968~1978年;社会因素在铁道车祸发生中起重要作用;7~8月和12~1月是行车事故高发月份;星期日事故最多,星期三最少:5:00~6:00、9:00~10:00和13:00~15:00是一天中事故高发时点。 相似文献
100.
ABSTRACT: The prevalence of headache and neck pain in farmers was determined by use of a questionnaire. Information about activities which increased the symptoms and about the treatments sought was also recorded. Results showed that 77.7% of farmers experienced neck pain and 79.2% experienced headache. Driving a tractor was the activity which was most frequently described as increasing symptoms in both conditions. While driving a tractor, farmers are exposed to whole-body vibration and assume a rotated neck posture. The contribution of these factors to the development of headache and neck pain is discussed. 相似文献