CO2 is obtained as a by-product from various sources. These can be chemical processes such as the production of hydrogen or ammonia synthesis, but also fermentation processes and natural sources. Depending on the source of CO2, different impurities may occur. Quality control of CO2 is thus an important area in the food and beverage industry. Any impurity - even trace amounts - can pose a potential health risk to the consumer. Therefore, strict requirements such as the EIGA and ISBT criteria are in place to guarantee the purity of CO2 as an ingredient. These regulations require the accurate determination of potential impurities.