Wearing a face mask does not put you at a higher risk of cancer. There is no current evidence linking the use of face masks to cancer, and science shows that any risks associated with wearing masks are low overall, while the benefits are high.
Because of how tiny oxygen and carbon dioxide molecules are, face masks neither decrease the amount of oxygen that enters a mask nor increase the amount of carbon dioxide that stays in a mask. As a result, face masks do not disrupt the body’s pH levels, affect the bloodstream, or alter one’s body in any way that would put someone at higher risk of cancer.
The claim that wearing face masks causes cancer has been circulating on Facebook and other social media platforms. While masks are restrictive and can feel like they impede air flow, properly designed masks do allow for air flow— the tiny size of oxygen and carbon dioxide molecules makes it easy for the molecules to travel freely in and out of the mask. The feeling of inconvenience or minor discomfort in a mask does not lead to health risks such as a build up of carbon dioxide. It’s true that too much carbon dioxide in the blood (hypercapnia), can lead to high levels of acid in the blood (respiratory acidosis), but both are very unlikely to happen as a result of wearing a properly designed mask or face covering.
Claims that the prolonged use of face masks can cause cancer, oxygen deficiency, dizziness, or other health challenges are not grounded in science. Healthcare workers often wear masks for long hours in the hospital and have been doing so for a long time. There is no evidence that surgical masks or cloth masks cause significant deficiency of oxygen, a build up of carbon dioxide, and other related negative health consequences. This information has been primarily circulating on social media among individuals or communities resistant to mask-wearing in general.
Wearing a mask is recommended to protect people from community transmission of COVID-19. There are only a few exceptions to this public health recommendation, mostly focused on children under 2 years of age and people with serious medical conditions that can make it difficult to breathe through a mask or remove a mask if necessary. Otherwise, wearing a mask is safe and helpful for preventing the spread of COVID-19.
We base our COVID-19 expert contextualizations on information provided by internationally-recognized health organizations, public health researchers and infectious disease experts. Because information in epidemics is constantly being updated, our content is up to date based on the date and time they are published. If you’re looking for medical advice, please contact a healthcare provider, and be sure to review the World Health Organization website for more information about COVID-19.