‘Masks don’t reduce your oxygen levels:' Doctor debunks facial covering claim in experiment

LOS ANGELES -- The simple act of wearing a mask amid the ongoing COVID-19 pandemic has become a politically charged topic in the U.S. and across social media. Despite the urgings of public health officials and pleas from doctors in hard-hit hospitals across the country, some people have still refused to don a facial covering, citing widespread disinformation about alleged negative health effects of mask wearing.

One Irish doctor set out to prove mask detractors wrong in an experiment that debunked the claim that wearing a facial covering negatively impacts the wearer’s oxygen levels.

Dr. Maitiu O Tuathail, a doctor based in Dublin, shared on Twitter that patients repeatedly ask him whether masks affect oxygen levels.

He conducted the test in response to the queries, and he found that the results did not show a lowering of oxygen levels.

The video, posted Tuesday, showed O Tuathail putting six face masks on his face as he recorded his pulse rate on a pulse oximeter.The pulse oximeter showed no change in the doctor’s oxygen levels after putting on the medical coverings.

“Face coverings / masks don’t reduce your oxygen levels!,” O Tuathail said. “I managed to get six masks on and it has no effect on my oxygen levels.”

According to the American Lung Association, there has been a tremendous amount of disinformation spreading regarding the use of masks.

Dr. David G. Hill said masks “absolutely” do not cause lower oxygen levels.

“We wear masks all day long in the hospital. The masks are designed to be breathed through and there is no evidence that low oxygen levels occur,” Hill said.

Hill said there is some evidence that prolonged use of N-95 masks in patients with preexisting lung disease could cause some build-up of carbon dioxide levels in the body.

“People with preexisting lung problems should discuss mask wearing concerns with their health care providers,” Hill said.

“Mask use has become politicized which is unfortunate when it comes to public health,” Hill continued.

Numerous studies have shown that wearing a mask is an effective way to lower the risk of COVID-19 transmission.

According to a widely-cited coronavirus pandemic model used by the White House, if almost everyone wears a mask in public over the next few months, tens of thousands of lives could be saved in the United States.

The projections, from the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, compared different actions to control the spread of COVID-19.

"People need to know that wearing masks can reduce transmission of the virus by as much as 50 percent, and those who refuse are putting their lives, their families, their friends, and their communities at risk," IHME said in a statement.

Dr. Richard Davis, a clinical microbiology lab director at Providence Sacred Heart Medical Center in Spokane, Washington, shared a series of photos on Twitter of an experiment which demonstrated the effectiveness of wearing a facial covering amid the ongoing pandemic.

The doctor’s experiment showed how effective masks were at blocking respiratory droplets from an individual’s mouth.

Every action performed unmasked nearly covered a petri dish in bacteria, while the action performed with a mask left the petri dish nearly untouched.

But Davis found that the material of your mask does matter.

A recent study from Florida Atlantic University, titled “Physics of Fluids,” found which types of masks offer the best protection against the novel coronavirus.

Researcher Siddhartha Verma and his team experimented with different choices in material and design to “determine how well face masks block droplets as they exit the mouth,” the study explained.

The researchers found that well-fitted homemade masks with multiple layers of quilting cotton offered the best protection. These masks significantly reduced the number of droplets, according to their findings.

While studies continue to illustrate that masks are important, Verma said that they are not a substitute for social distancing.

“If you take a look at the visuals, you can see there’s a lot of leakage from the sides and from the top, even for the best mask.” Verma said. “So masks are not 100 percent effective. Using a mask doesn’t reduce the risk of transmission to zero. That’s why it’s so important to use a combination of masks and social distancing.”

Storyful contributed to this story.