In the field of forensic analysis of glass the aim in most cases is to prove or disprove the common origin of two (or more) sources of glass. Glass isolated from clothing of a suspect is compared to broken glass originated from a scene of crime in order to link these together. Based on the given merits, LA-ICP-MS is an excellent tool for the analysis of glass fragments. In this paper, a compromise match criterion for glass casework is established and optimised in order to produce low Type 1 (false negative) error rates and low Type 2 (false positive) error rates at the same time. Glass from two sets (fragments originating from the same float glass pane and fragments originating from different float glass of global origin) were analysed using laser ablation-inductively coupled plasma-mass spectrometry. Comparisons of the quantitative results for 18 element concentrations (Li,

Quantitative (1)H NMR (qNMR) is a widely applied technique for compound concentration and purity determinations. The NMR spectrum will display signals from all species in the sample, and this is generally a strength of the method. The key spectral determination is the full and accurate determination of one or more signal areas. Accurate peak integration can be an issue when unrelated peaks resonate in an important integral region. We describe a "hybrid" approach to signal integration that provides an accurate estimation of signal area, removing the component(s) that may arise from unrelated peaks. This is achieved by using the most accurate integration method for the region and removing unwanted contributions. The key to this performing well, and in almost all cases, is the use of areas from deconvolved peaks. We describe this process and show that it can be very successfully applied to cases where the highest precision is required and for more common cases of NMR-based quantitation.

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In Europe, more than 50 approved cultivars of fiber hemp (Cannabis sativa L.) are in agricultural production. Their content of psychoactive tetrahydrocannabinol (THC) is legally restricted to <0.2% (%w/w in the dry, mature inflorescences). Cannabis strains with much higher THC contents are also grown, illegally or under license for drug production. Differentiation between these two groups relies on biochemical quantification of cannabinoid contents in mature floral material. For nonflowering material or tissue devoid of cannabinoids, the genetic prediction of the chemical phenotype (chemotype) provides a suitable method of distinction. Three discrete chemotypes, depending on the ratio of THC and the noneuphoric cannabidiol (CBD), can be distinguished: a "THC-predominant" type, a "CBD-predominant" type, and an intermediate chemotype. We present a systematic genetic prediction of chemotypes of 62 agricultural hemp cultivars grown in Europe. The survey reveals the presence of up to 35% B T allele-carrying individuals (representing either a THC-predominant or an intermediate chemotype) in some cultivars-which is unexpected considering the legal THC limit of 0.2% THC. The fact that 100% of the seized drug-type seeds in this study revealed at least one B T allele, reflects that plant breeding efforts have resulted in a fixation of the B T allele in recreational Cannabis. To guarantee a sincere forensic application based on a genetic chemotype prediction, we recommend not to classify material of unknown origin if the samples size is below nine genetically independent individuals.In Europe, more than 50 agricultural hemp cultivars are grown and should contain <0.2% (w/w) of Δ 9 -tetrahydrocannabinol (THC), their main psychoactive cannabinoid constituent, in the mature dry inflorescences. Additionally, numerous strains with a THC content of up to 20-25% are grown for drug production. Differentiation between these two groups relies on the quantitative biochemical assessment of cannabinoid contents and ratios in mature floral material. For nonflowering material (e.g., very young seedlings) or material devoid of cannabinoids (seeds and roots), the genetic assessment of the chemical phenotype (chemotype) provides an alternative and quick means of differentiation (1).The ratio of THC and the noneuphoric cannabidiol (CBD) remains constant throughout the plant´s life and is not affected by external factors (2-4). Based on the CBD/THC ratio, three discrete chemotypes can be distinguished: a THC-predominant type (CBD/THC ratio 0.00-0.05), a CBD-predominant type (CBD/THC ratio 15-25), and an intermediate phenotype (CBD/ THC ratio 0.5-3). The CBD/THC ratio appears to be under the control of a simple inheritance mechanism. According to a model by (5), it is determined by a single locus (B) with two codominant alleles (B T and B D ). The homozygous B T /B T genotype underlies the THC-predominant phenotype, and B D /B D is CBD-predominant. The intermediate phenotype is induced by the heterozygous state (B T /B D ).Through a linkage stu...

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