The N95 surgical mask is considered the gold standard when it comes to Covid protection.
But a study quietly re-shared in the spring by the National Institutes of Health suggests the tight-fitting mask could expose users to dangerous levels of toxic chemicals.
Researchers at South Korea’s Jeonbuk National University looked at two types of medical-grade disposable masks, as well as several reusable cotton masks.
The study found that the chemicals released by these masks were eight times the recommended safety limit of toxic volatile organic compounds (TVOCs).
Inhalation of TVOCs has been linked to health problems such as headaches and nausea, while prolonged and repeated exposure has been linked to organ damage and even cancer.
A study published in April found that several disposable masks contained more than eight times the US recommended limit of toxic volatile organic compounds (TVOCs).
Samples A1 through B3 represent disposable masks, while samples C1 through E4 are cloth masks. Disposable masks had up to 14 times more TVOCs than cloth masks
“It is clear that particular attention should be paid to the VOCs associated with the use of KF94 (medical) masks and their effects on human health,” the researchers wrote in the study published in April.
However, there are ways to reduce the danger, they said. “Exposure can be significantly reduced if a mask is opened and left on for at least 30 minutes,” the researchers wrote.
This suggests that the packaging of these masks could play a role in the amount of chemicals they contain.
The study was published in the journal Ecotoxicology and Environmental Safety and on the NIH website.
The NIH said, “Inclusion in an NLM database does not imply endorsement or agreement of the content by NLM or the National Institutes of Health.”
The researchers found that levels of TVOCs were 14 times lower in cloth masks and posed no risk to human health.
However, the study did not measure the effect of people actually wearing the masks.
Dr. Stuart Fischer, an internist in New York, told DailyMail.com that no strong conclusions could be drawn from the study.
He did say, however, that mounting evidence has shown the downsides of wearing masks. He added that “the return on the need for masks seems to be declining.”
In the latest study, researchers tested 14 disposable and cloth masks purchased online by measuring the amount of TVOCs in them. The disposable masks were KFAD and KF94 models, which were made of thermoplastic polypropylene and polyurethane-nylon.
These masks have become popular in South Korea, where the research was conducted, while KN95s are more popular in the US.
However, their differences are minuscule. KFADs and KF94s filter 94 percent of particles, while KN95s filter 95 percent.
The cloth masks were made of cotton, ramie – a plant fiber – and polyurethane.
“These TVOC concentration levels corresponded to a level that is harmless to the human body (no relevant health-related problems),” the researchers wrote.
However, the disposable masks contain up to 14 times more TVOCs than cotton masks.
The Environmental Protection Agency (EPA) recommends keeping indoor air TVOC levels below 0.5 parts per million.
The sample with the highest amount of TVOCs had 4,808 cubic meters per microgram, which is about 4.8 parts per million.
That’s more than eight times the recommended limit.
TVOCs are a large group of odorous chemicals, many of which are released from cleaning and beauty products, fuel burning and cooking.
Sources of TVOCs in the home include aerosol sprays, cleaners and disinfectants, moth repellents, air fresheners and automotive products.
Other sources include building materials and furniture, office equipment such as copiers and printers, permanent markers, correction fluids, carbonless copy paper, and craft materials, including glues and adhesives.
According to the American Lung Association (ALA), TVOCs have been shown to irritate the eyes, nose and throat, cause difficulty breathing and nausea, and damage the central nervous system and organs such as the liver.
Some are even considered carcinogenic to humans, meaning they can cause cancer.
The researchers specifically pointed to the chemicals dimethylacetamide (DMAc) and dimethylformamide (DMF) as they are linked to liver and reproductive damage.
The team acknowledged that the sample size was small and that they had not tested several other popular disposable masks, such as KN95s.
The study builds on previous research suggesting that wearing masks may cause more harm than good.
For example, research from the Cochrane Institute suggested that face masks made “little to no difference” in Covid infections and deaths.
The researchers said the harms caused by masks — including hindering children’s schooling — were poorly measured in the studies, meaning any small benefit in infection rates may be negated.
And a controversial study suggested that wearing face masks increases the risk of stillbirth, testicular dysfunction and cognitive decline in children.
However, experts have criticized the study for drawing conclusions without good evidence.
“It is indeed possible that certain masks have side effects, just as certain beneficial drugs (antihistamines, psychotropic drugs, antibiotics) have side effects,” Dr Fischer said.
“Almost everything in healthcare has a benefit-side effect profile.”
Although the findings were published in April, the research could have new relevance as Covid variant BA.2.86 spreads across the US.
Several universities, hospitals, and even Hollywood studio Lionsgate reinstated mask mandates during the surge.
But the newly discovered dangers of masks—typically considered the most protective—may render mask mandates ineffective.
“I think following the general recommendations could be helpful, but it’s not yet clear whether we need the sweeping edicts from three years ago,” said Dr Fischer.
“Extreme fears about the lethality of Covid may have led to decisions that were counterproductive.”
“Covid won’t be going away for a long time. We urgently need policies that do not destroy our society and at the same time offer minimal protection.’