We came across this message being circulated on Telegram:

The author of the message asks if ART and PCR tests are “coated with [a] small amount of cancer causing chemicals”, and if they are safe to use.

ART (Antigen Rapid Test) and PCR (Polymerase Chain Reaction) tests are used to test for COVID-19 infection, and typically involve the use of a nasal swab. The ART can be self-administered, is relatively less invasive, and provides results in a shorter time (less than 20 minutes) while the PCR test is to be performed by a trained professional, is more invasive, and takes around six hours to up to 12 hours to produce a result.

From 28 August to 27 September, packages of six ART kits were distributed to all households as part of Singapore’s strategy to step up COVID-19 testing efforts. The Ministry of Education (MOE) also announced on 20 October that primary school pupils would be required to take ART every two weeks until school closes.

Given how prevalent the use of ART and PCR test swabs are, it is definitely worrying if there is any semblance of truth in the statement made.

Similar claims have been made across different countries

This concern has actually been fact-checked by multiple publications, with similar claims being made in other countries.

In a particular video flagged by Reuters, a man is seen refusing to take a swab test and asking the tester to show him the packaging of the test kit. He then points out the “sterile EO” note printed on the packaging, explaining that ‘EO’ stands for ethylene oxide, the “number one ingredient used in antifreeze [and] a massive carcinogen”. A carcinogen is something that can cause you to have cancer.

In another Facebook post shared by an Australian user flagged by AAP Factcheck, we see the similar claim being made about the PCR test containing ethyl oxide, and that it is “carcinogenic and mutogenic (sic)”.

We see another Facebook post, flagged by Full Fact, which calls on parents to not let their children take swab tests:

As seen in the screenshot, photos of what appear to be the informational booklet of a self test kit (ART) are posted. A circle is also drawn to point out the note that the kit is “sterilised using ethylene oxide”.

When we did a check on the informational booklet of Panbio COVID-19 self-test kit uploaded by the Health Sciences Authority of Singapore (HSA), we see that there is indeed a note stating “sterilised with ethyl oxide” printed under the ‘Glossary of Symbols’ section.

True that exposure to ethylene oxide poses a health risk, but…

According to the National Cancer Institute in the US, ethylene oxide is a flammable colourless gas that is used primarily to produce other chemicals, including antifreeze. In smaller amounts, ethylene oxide is used as a pesticide and a sterilising agent. The website also notes the health risks that come with exposure to the gas, which include lymphoma, leukaemia, and stomach and breast cancers.

The US Food and Drug Administration (FDA) notes that about 50% of all sterile medical devices in the U.S. are sterilised with ethylene oxide. This ranges from devices used in general health care practices (for example, wound dressings) to more specialised devices used to treat specific areas of the body.

This is where the big ‘however’ comes in.

Given the risks that come with acute and chronic exposure to ethylene oxide, agencies like FDA ensure that manufacturers of sterile medical devices choose sterilisation methods that are “in accordance with internationally agreed upon voluntary consensus standards”. Specifically, the consensus standards include how to develop, validate and control ethylene oxide sterilisation processes, and the acceptable levels of residual ethylene oxide and ethylene chlorohydrin left on a device after it has undergone ethylene oxide sterilisation.

“These standards help ensure levels of ethylene oxide on medical devices are within safe limits since long-term and occupational exposure to ethylene oxide has been linked to cancer,” noted the FDA.

In a factcheck by Reuters, a spokesperson for the United Kingdom’s Department of Health and Social Care said that “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”, and that these tests “have been rigorously tested and are safe to use on a regular basis”.

Dr Alexander Edwards, associate professor in biomedical technology at the University of Reading, also told Reuters that given that ethylene oxide is a gas, “there is no way it can be carried forward after the manufacture into any of these products”. He added: “We know this from decades of safety and toxicity research. The use is strictly controlled and regulated.”

He added: “It’s a bit like using bleach at home. People are generally happy to use dilute bleach or detergents and antiseptics to sterilise surfaces. No one would think of eating or drinking the bleach- that would be incredibly dangerous. But we also know it’s safe if you use it carefully.”

Professor Andrea Sella, professor of inorganic chemistry at University College London, told Full Fact that “the sterilisation process involves exposing a material to ethylene oxide for a few seconds or minutes, and then removing the gas entirely”, so there is essentially “nothing left of the ethylene oxide once it is packaged, and there is no conceivable harm that can come from using an item sterilised in this way”.

Professor Bill Rawlinson, senior medical virologist from UNSW also told AAP FactCheck that any residual amounts of ethylene oxide in PCR swabs would almost be immeasurable, since “there’s just not enough (ethylene oxide) left over; and if it were left over, time and exposure means that any residual ethylene oxide becomes denatured and becomes non-reactive”.

Therefore, while is it true that ethylene oxide is indeed used in the sterilisation of some medical devices (including PCR and ART kits) and that chronic and acute exposure to it can cause cancer, it is misleading and false to say that doing ART and PCR tests pose health risks to individuals.