Howard Fischer/Capitol Media Services

Kelly Townsend

Before the legislative session ended, state Rep. Kelly Townsend tweeted she will not wear a face mask because she has, "17 pre-COVID scientific, peer-reviewed studies/references that detail the health risks of prolonged wearing of face masks."

The tweet included the hashtag #MyBodyMyChoice. Townsend has since followed up with a longer Facebook post.

The remarks add fuel to an increasingly politicized fight over facemasks — an argument that has divided the Legislature along political and sartorial lines.

But when it comes to wearing masks, experts say our bodies might not be the only ones we are choosing for. This is the philosophy behind "flattening the curve" — observing social distancing to reduce the spread of COVID-19 and keep hospitals from being overwhelmed, thereby reducing avoidable deaths.

The Centers for Disease Control and Prevention recommends using cloth face masks both to guard against others' virus-containing droplets reaching the nose and mouth and to limit the wearer's capacity to spread germs in the same way.

Such precautions are particularly important when the coronavirus can spread when no symptoms are present.

The counterargument says masks cause harm by interfering with healthy breathing while not providing added protection.

KJZZ reached out to Townsend for her 17 references. While awaiting her response, KJZZ's Arizona Science Desk identified and reviewed the five papers whose titles were visible in the photo accompanying the tweet.

Two were duplicates in different fonts of a preliminary study of the effects of N95 masks on surgeons during operations and offered inconclusive results.

Another described the potential harms of giving patients with coronary artery disease too much oxygen.

One article, on the website Technocracy, was written by Russel Blaylock, a retired surgeon who writes books and articles opposing vaccines, raising concerns about chemtrails and promoting alternative medicine and nutrition.

A fifth, an article on the website Explore Health, explained the difference between N95 masks, which it said should be reserved for medical personnel and emergency responders, and cloth masks, which the article in fact recommended.

The sixth article was obscured.

Of the references Townsend provided, which included another two sets of duplicates and a number of post-COVID-19 studies, some were reviews and not original data. Others were small or preliminary studies. Still others had nothing do with masks or COVID-19.

For example, one study described sleep apnea's effects on high blood pressure. Another was a review of oxygen deprivation in tissues in people with cardiovascular diseases.

Neither involved protective masks or COVID-19.

A number of articles included passages that seemed to caution against masks, but then went on to recommend them.

A 2014 article in the journal Risk Analysis illustrates this point. Rep. Townsend's materials quoted it as saying, "N95 filtering facepiece respirators and surgical masks ... can become contaminated with respiratory pathogens during use, thus serving as potential sources for transmission."

However, the article also said surgical masks "reduce contamination ... from particles generated by the wearer and provide a barrier to ... splashes and sprays of body fluids such as blood," and that both N95 respirators and surgical masks "restrict users from touching their mouth and nose, which limits opportunities for contact transmission of respiratory pathogens from the hands to the mucosa of the wearer."

Lead author Edward Fisher is a biologist with the National Personal Protection Technology Laboratory, part of the National Institute for Occupational Safety and Health at CDC. In an email, he emphasized his research "did not address the use of face masks by the public."

"Any facemask can become contaminated. That is why cloth facemasks should be washed regularly," he said.

Another example, a Korean study describing the subjective discomfort felt by industrial workers who wore N95 and other respirators for long periods, said N95 masks "have no significant effect on pulmonary function in healthy people or patients with mild respiratory issues."

It merely urged caution among "patients with low pulmonary function and high levels of respiratory distress."

That agrees with CDC guidelines, which recommend against using cloth face coverings "on young children under age 2, anyone who has trouble breathing, or is unconscious, incapacitated or otherwise unable to remove the mask without assistance."

Most references provided by Townsend focused on N95 masks, likely because they provide the greatest protection. If they fail to guard against COVID-19 transmission, presumably cloth face masks will fare worse.

As some of these papers explain, Individual coronavirus particles are smaller than the pore size of N95 respirator masks. N95 masks filter 95 percent of airborne particles with a median size of 0.3 micrometers or larger. That's 300 nanometers, or roughly 2-4 times the size of a coronavirus particle.

But that size discrepancy does not alone render masks useless. A golf ball can fit through the holes in a tennis net, but someone on the wrong side of a driving range might consider it better than nothing.

Moreover, as another study provided by Townsend pointed out, "the particle size of 0.5-10 micrometers are of distinct importance as they are most likely to transmit infection."

Such particle sizes lie well within the N95 filtration range. Moreover, most makes incorporate more than one layer. Perhaps that's why many articles describing issues with N95 masks still recommended them to medical personnel.

Studies also show even disposable surgical masks can reduce the transfer of respiratory droplets. They also block blood and bodily fluids from reaching the wearer's mouth and nose.

And at least one reference provided showed surgical masks might do as well as N95 respirators in slowing the spread of the 2009 H1N1 influenza, which has a similar particle size to SARS-CoV-2, the coronavirus that causes COVID-19.

Of course, cloth masks are not surgical masks and certainly not N95 substitutes. And, as another study provided by Townsend explained, repeated use and cleaning can degrade masks' protective value.

As for whether the protective masks cause harm, particularly with respect to breathing, research is sparse and again focuses on N95 and surgical masks, which are generally reserved for firstline responders and medical personnel.

The same filtration that helps N95 masks keep harmful microbes out can slightly restrict oxygen and slightly increase carbon dioxide if worn for long periods. This discomfort can lead medical personnel to take them off, as can associated skin irritations and their potential to cause or worsen headaches.

Townsend shared no such studies concerning cloth face.

In summary, experts advise common sense: Don't wear a mask except in situations that warrant one and don't wear it longer than necessary. People who start feeling physical symptoms should find a safe place and take theirs off.

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