Karolina Sekuła

Cannabis is the most widely used drug. in recent years, interest in cannabis has grown significantly. over the last decade, the number of cannabis users worldwide has increased by almost 21%, reaching approximately 219 million people in 2021. Can- nabis cultivation covers practically all regions of the world. In recent years, 151 countries have reported cannabis cultivation, both outdoors and indoors. The increased growth of the latter is particularly observed in North America and Europe. Global data shows that in 2021, 5,226 tons of marihuana and 2,014 tons of hashish were confiscated. an increase in seizures of can- nabis products is observed in Europe and Poland. Another trend concerns the increasing content of the psychoactive substance Δ⁹-tetrahydrocannabinol (Δ⁹-THC) in cannabis plants. According to UNODC data, over the last 25 years there has been a 4-fold increase in the content of Δ⁹-THc in cannabis. over the last decade, the average content of Δ9-tetrahydrocannabinol in marihua- na seized in europe has increased approximately twice, and in hashish three times.

The aim of this work is to assess potential changes in the content of the main psychoactive ingredients in cannabis in Poland in the last decade (2012–2022), based on expert opinions developed by the Institute of Forensic research in Kraków. The conduct- ed analyses confirmed the trends observed around the world. in the last ten years, the number of cases in which the drug-type cannabis was detected increased from 5.3% to 68.4% of total number of illicit drug cases examined for the presence of narcotic drugs, psychotropic substances and new psychoactive substances. an increasing trend in the content of Δ⁹-THC in the drug-type cannabis was also noted. over the last decade, the average total content of Δ⁹-THC increased almost three times and in 2022 reached 12%. This is due to the growth of cannabis cultivation in Europe, carried out using the technique known as sinsemilla, genetic modifications, as well as the appearance on the market of the feminized cannabis seeds.

The aim of the study was to determine the components of measurement uncertainty in the concentration of alcohol in exhaled breath and to determine the state of sobriety at the time of incident. Based on the literature review and the authors’ experience in providing opinions for law enforcement and the judiciary, the influence of various factors on the final interpretation of sobriety state is described on the basis of measurement uncertainty of breath analyzers, uncertainty of retrospective and prospective calculations, and uncertainty related to the conversion of alcohol concentrations detected during breath and blood tests. The paper pays particular attention to interpreting the concentrations of ethanol in exhaled breath close to the legal limits of the state of sobriety and the state after alcohol use, or the state after alcohol use and the state of insobriety.

Analyzing the results of an exhaled breath test concerning concentrations close to the values of 0.1 mg/dm3 and 0.25 mg/dm3, it is necessary to take into account the factors affecting the measurements obtained, including the measurement uncertainty of the determination of alcohol in exhaled breath, the processes of absorption, distribution and metabolism of ethyl alcohol, and the possibility of the presence of alcohol lingering in the oral cavity. The incorrect execution of measurements of the tested person’s alcohol concentration is also a problematic issue. When determining sobriety state by means of retrospective and prospective calculations, it is important to remember that the uncertainty of the result is affected by a number of factors and depends, among other things, on the information provided by the suspect. Hence, the expert should draw conclusions particularly cautiously and any overestimation or underestimation of the components of uncertainty can lead to erroneous conclusions. Awareness of the uncertainties inherent in the results of a sobriety test or alcohol calculation allows for meaningful interpretation of test results and determination of the sobriety state of the person tested.

In cases requiring determination of the ethanol content of a person involved in a road incident, expert opinions are often based on prospective calculations. Declarations regarding the amount and type of alcoholic drink consumed are used to calculate the concentration of alcohol in the body and to correlate the results obtained with those of sobriety tests. alcohol concentration estimated using a prospective calculation should correspond most accurately with the ethanol content in the body. It is therefore desirable to identify the appropriate model of prospective estimation, which is accomplished here by comparing the most common methods of alcohol calculation used by forensic experts. The study involved five people aged 29–64 (two women and three men) who were given alcohol in an amount leading to a theoretical ethanol concentration of 1‰in their bodies. In this paper, we plotted the alcohol curves and compared the experimental (real) ethanol concentration with the theoretical values calculated by the various methods. The best correlation between the results of prospective calculations and real ethanol concentrations was obtained for the method that assumes an immediate elimination from the beginning of consumption (used routinely by the authors) and for the method that assumes an absorption time of 30 minutes and a 10% alcohol deficit (the difference between the theoretical and actual ethanol concentration).