The nasal swabs have been sterilised with ethylene oxide (EO). Ethylene oxide is used to sterilise medical equipment. The nasal swabs that we use, like the rest of the test kit, are CE certified and approved by the EU. In order to place a CE mark on medical equipment, the manufacturer must document the quality, safety and efficiency of the product. Read more about CE marking here: https://laegemiddelstyrelsen.dk/da/udstyr/ce-maerkning/