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Posts falsely claim that wearing face masks harms health

June 26, 2020 GMT

CLAIM: Face masks can decrease oxygen intake, increase toxin inhalation and shut down the immune system. 

AP’S ASSESSMENT: False. Medical professionals say wearing masks do none of those things. 

THE FACTS: Posts on social media are spreading false information about face masks as health officials encourage their use to halt the spread of the new coronavirus. The number of confirmed daily infections surged to an all-time high in the U.S. this week  

One post with more than 5,000 Facebook interactions lists what it says are mask safety facts. The post offers a series of false statements, including that masks decrease oxygen intake and increase toxin inhalation. Those factors, the post goes on to claim, shut down the immune system, putting the body under more stress. 


But none of that is true. Medical professionals have turned to social media to debunk claims about oxygen levels and masks. Videos and photos online show medical professionals getting the same normal rating on pulse oximeters, which measure oxygen saturation, with a mask on or off. 

Dr. Michael Niederman, a pulmonologist at Weill Cornell Medicine, said that wearing masks does not decrease oxygen levels, nor does it increase carbon dioxide levels. 

“There’s no evidence that I know of that they are going to harm anyone,” he said. 

Dr. Russell Buhr, a pulmonary and critical care physician at UCLA Health, said gas molecules are much smaller than the pores in the material so there is no significant restriction keeping the gas from moving through the mask material. 

“Medical professionals wear these masks for hours a day for entire careers,” Buhr said. “So the thought that the bandana that you repurposed to cover your face is going to decrease the amount of air that you breathe or the amount of oxygen you get is not supported in any sort of scientific evidence.”

The post goes on to suggest that masks increase your risk to viruses by triggering dormant retroviruses in the body, taking advantage of immune systems compromised by mask wearing. 

Dr. Bruce Polsky, chairman of Medicine at NYU Winthrop Hospital, told The Associated Press that humans do not typically have dormant retroviruses like HIV.


“The concept behind masks in a respiratory pandemic situation is if everyone wears a mask as they should be then everyone is protected because there will be no opportunity for me to infect you and no opportunity for you to infect me if we are both wearing masks,” he said. 

The post further says that due to the tiny molecular size of the virus, masks cannot prevent the virus from entering, comparing the virus to a mosquito going through a chain link fence. But this statement is misleading on two fronts.

One, the droplets that spread the virus are much larger than the virus itself, said Vincent Racaniello, a professor of microbiology and immunology at Columbia University.

In addition, masks are not designed to stop the virus from entering someone’s respiratory system, it is meant to stop it from spreading from the infected person.

Finally, the post falsely states that the effectiveness of masks has not been studied. In June, The Associated Press reported on a peer-reviewed  study funded by the World Health Organization in The Lancet. The study found that masks and social distancing were effective in controlling the spread of the virus along with other safety precautions like hand washing. The report also said that none of the methods researched offered complete protection from the coronavirus and that more studies were needed. 

False claims around masks have been running rampant online. Earlier in the week, the AP debunked false posts suggesting that masks could cause fungal or bacterial infections in the respiratory airways.


This is part of The Associated Press’ ongoing effort to fact-check misinformation that is shared widely online, including work with Facebook to identify and reduce the circulation of false stories on the platform.

Here’s more information on Facebook’s fact-checking program: