Problematyka walidacji metody oznaczania 1,3-butadienu w skroplonych gazach węglowodorowych

According to the requirements of Regulation (EC) No 1907/2006 of the European Parliament and of the Council (REACH), in the part concerning the presence of carcinogens and mutagens in liquefied hydrocarbon gases (LPG), the necessity of determining the content of 1,3-butadiene at a level below 0.1% (m/m) in this product has been indicated. The content of 1,3-butadiene below 0.1% (m/m) in LPG abrogates its classification as a carcinogen or mutagen. However, accurate testing of 1,3-butadiene content at such a low level of LPG content is not possible pursuant to a method such as the EN 27941:2015-12 standard used for testing LPG composition in the European Union, because the determined parameters of the method precision given in this standard are insufficient to achieve the purpose. Therefore, the latest European specification for LPG describing the requirements and test methods cites the German standard DIN 51619:2004-02, which allows the determination of low contents of 1,3-butadiene, i.e. from 0.01% (m/m). The mentioned standard should be implemented into laboratory practice and accredited in Polish laboratories dealing with qualitative LPG testing. Validation and confirmation of the possibility of using the DIN 51619:2004-02 method can be a great challenge for research laboratories due to the necessity to determine 1,3-butadiene below 0.1% (m/m) in LPG with a method not previously used in the conditions of Polish laboratories. A particular problem may be the LPG evaporation equipment used in the Standard. This paper presents the elements of validation and checking the possibility of using the method of determination of 1,3-butadiene in liquefied LPG hydrocarbon gases according to DIN 51619:2004-02 in an analytical laboratory. This article outlines the issue of method validation, especially in terms of compliance with accreditation requirements. The article also presents the results of testing a number of LPG samples from the Polish liquefied gas market, tested for 1,3-butadiene. The presented test results can be used for the initial assessment of the level of content of the harmful 1,3-butadiene in commercial LPG samples found on the Polish liquefied gas market.