The surgical N95 mask has been held up as the gold standard when it comes to protecting against Covid.
But a study quietly re-shared by the National Institutes of Health in spring suggests the tight-fitting mask may expose users to dangerous levels of toxic chemicals.
Researchers from Jeonbuk National University in South Korea looked at two types of disposable medical-grade masks, as well as several reusable cotton masks. The study found that the chemicals released by these masks had eight times the recommended safety limit of toxic volatile organic compounds (TVOCs).
Inhaling TVOCs has been linked to health issues like headaches and nausea, while prolonged and repeated has been linked to organ damage and even cancer.It is clear that particular attention must be paid to the VOCs associated with the use of KF94 [medical] masks their effects on human health,' the researchers wrote in the study published April.
However, there are ways to reduce the danger, they said. 'Exposure can be significantly reduced if a mask is opened and left to sit for at least 30 min,' the researchers wrote.
This suggests that the packaging of these masks could play a role in the amount of chemicals they have.
The study was published in the journal Ecotoxicology and Environmental Safety and on the NIH's website.
The NIH said: 'Inclusion in an NLM database does not imply endorsement of, or agreement with, the contents by NLM or the National Institutes of Health.'
The researchers found that the levels of TVOCs were 14 times lower in cloth masks and didn't pose a risk to human health.
However, the study did not measure the effect of people actually wearing the masks.
Dr Stuart Fischer, an internal medicine physician in New York, told DailyMail.com that strong conclusions couldn't be drawn from the study.
However, he did say that increasingly evidence has shown the drawbacks of mask-wearing. He added that 'there seems to be diminishing returns on the need for masks.'
