Påvisning av pepperspray i tekstiler

On Saturday 15 February 2014, the Norwegian Defence Research Establishment (FFI) was requested by the Oslo Agency for Fire and Rescue Services (OBRE) to investigate the clothing of an individual that had been exposed to a spray with unknown content. FFI received the clothing on Saturday night, and investigations were performed the following day in the laboratory for identification of hazardous chemicals. The results of the investigation showed that the clothing had been exposed to pepper spray. This was reported to OBRE on the afternoon of 16 February. The person exposed to the spray sought medical care due to physical discomfort after the incident. At the casualty clinic, several persons experienced physical discomfort when being exposed to the chemicals in the spray, evaporating from the clothing. A quick response was thus important to clarify what type of chemicals the involved persons had been exposed to. Remains of pepper spray were identified by extracting selected parts of the clothing with two solvents, in which the content of the extracts were investigated by chemical analysis methods. Dichloromethane and water/isopropanol (50/50) were used for extraction, and the extracted compounds were identified by gas chromatography and liquid chromatography with mass spectrometric detection. A class of compounds known as capsaicinoids were found in the extracts. These are active ingredients of chili pepper and used to give the desired effect of pepper spray. The presence of the two main capsaicinoids in pepper spray (capsaicin and dihydrocapsaicin) was confirmed by comparing analyses of reference standards. These compounds were found in the dichloromethane extracts of the received jacket and shirt, and in the water/isopropanol extracts of the jacket, shirt and sweater. In addition, four other capsaicinoids were identified at trace amounts on the jacket, shirt and sweater. Polyethylene glycols and diethylene glycol monobutyl ether were also identified on the clothing. Glycols are commonly used to solve the active ingredients in pepper spray. Based on the findings of capsaicinoids on the clothing, it could be concluded that they had been exposed to pepper spray. This report gives a detailed description of the investigation of the clothing, from sample preparation to interpretation of the analysis results.