Fact Check-Nasal swabs sterilised with ethylene oxide are safe to use; the sterilisation process is tightly regulated by international standards 

Claims that the British government is “purposefully killing” people by using nasal swabs sterilised with ethylene oxide (EO) to test for the novel coronavirus are false. The EO sterilisation process is safe, has been used for decades on medical equipment, and is tightly controlled by international standards.

Following a viral video on the same topic debunked by Reuters last week (here), multiple social media users have continued sharing different clips that discuss EO sterilisation in lateral flow tests.

One video shows a man holding up an NHS COVID-19 self-test kit, which confirms on the packaging it has been sterilised with ethylene oxide. The man says: “They’re purposefully killing us…Now what they’re doing, they’re spraying the end of the swabs, apparently to sterilise them, in ethylene oxide. If you google ethylene oxide, it is the biggest cancer-causing chemical listed on” (here , timestamp 1.23). Comments beneath the video show viewers are concerned, with examples such as: “I’ve seen so many of these and my kids certainly ain’t being tested”. The same clip has also been subtitled in Spanish (here), Croatian (here) and German (here).

Another video, which was posted on March 15 and has been viewed over 17,900 times, features a man discussing the same topic. He says: “Ethylene oxide is present in all lateral flows tests that are being administered in schools across the country. A quick search and you’ll find that ethylene oxide is a highly toxic chemical… As we are led to believe, the information on the government’s website is to be true. So they’re saying it is carcinogenic, and they’re saying it’s cancer inducing.” (here)

A clip viewed 9,100 times on Facebook shows an individual presenting a COVID-19 self-test kit said to have been given to their children. They lift a swab to the camera and say: “So basically they sterilise that with ethylene oxide, which causes cancer and damages your DNA.” (here , here , here and here timestamp 0.39).

Other variations of the claim have been shared on Facebook here , here and here , while nearly 100 people have signed a petition on to “take ethylene oxide out of COVID-19 self-testing kits” (here).

While it is true to say ethylene oxide is a carcinogen, (here , here), and that its gaseous form is used to sterilise nasal swabs (here), it is not true to suggest the swabs are dangerous because of this process.

A major part of the sterilisation process ensures ethylene oxide residue is removed from the product (here) and makes certain that any EO left over is negligible, thereby meeting national and international safety standards (see UK legislation here , here and here , international requirements here and here , and EU rules here).

Ethylene oxide gas is commonly used to sterilise medical equipment (here) and has been for decades. In the US, 50% of medical devices are said to be sterilised this way (here and here).

In a previous fact check, the Department for Health and Social Care told Reuters: “Lateral flow tests have been rigorously tested and are safe to use on a regular basis. Any suggestion otherwise is inaccurate and harmful misinformation.

“Ethylene oxide is only used in the sterilisation of swabs and it is one of the most commonly used sterilisation tools in the healthcare industry, principally applied by manufacturers to keep medical devices safe.”


False. While it is true that ethylene oxide is carcinogenic, it is not accurate to say it poses a danger in medical swabs after sterilisation. The sterilisation process is tightly controlled to ensure any residue left over is negligible, making medical equipment safe to use.

This article was produced by the Reuters Fact Check team. Read more about our work to fact-check social media posts here .