The surgical N95 mask has been widely regarded as a top-tier defense against Covid. However, an understated study, subsequently shared by the National Institutes of Health (NIH), suggests that this snug-fitting mask might expose users to perilous levels of toxic chemicals.
Researchers from Jeonbuk National University in South Korea conducted a study encompassing two forms of disposable medical-grade masks and various reusable cotton masks. The study reveals that the masks emitted chemicals exceeding the recommended safety limit of toxic volatile organic compounds (TVOCs) by a factor of eight.
Breathing in TVOCs has been associated with health issues such as headaches and nausea, with extended and repeated exposure linked to organ damage and cancer. The researchers caution, “Particular attention must be paid to the VOCs associated with the use of KF94 [medical] masks and their effects on human health.”
The study underscores potential methods to mitigate risk: “Exposure can be significantly reduced if a mask is opened and left to sit for at least 30 min.” This suggests a possible connection between mask packaging and chemical emissions.
The study, featured in the Ecotoxicology and Environmental Safety journal and on the NIH website, was published in April.
The researchers contrast the TVOC levels, finding cloth masks exhibiting levels 14 times lower than disposable ones, thus posing no threat to human health. However, the study does not evaluate the actual effects of wearing the masks.
Dr. Stuart Fischer, an internal medicine physician in New York, advises cautious interpretation of the study’s findings, suggesting that concrete conclusions cannot be drawn.
Nonetheless, he acknowledges the increasing evidence of mask-related drawbacks and mentions diminishing returns on the necessity of masks. The study involves the assessment of 14 disposable and cloth masks purchased online. The disposable masks are KFAD and KF94 models made of thermoplastics polypropylene and polyurethane nylon, popular in South Korea where the study was conducted.
However, minor disparities separate them. KFADs and KF94s filter 94% of particles, while KN95s, more prevalent in the US, filter 95%.
Cloth masks, made from cotton, ramie (a vegetable fiber), and polyurethane, exhibit TVOC concentrations deemed safe for human health.
Comparatively, disposable masks contain up to 14 times the TVOCs found in cloth masks.
The study notes that the Environmental Protection Agency (EPA) suggests maintaining TVOC levels below 0.5 parts per million in indoor air. The highest TVOC concentration in the sample is approximately 4.8 parts per million, surpassing the recommended limit by more than eight times.
TVOCs are emitted by cleaning products, fuel combustion, and cooking. Sources in homes include aerosol sprays, cleansers, moth repellents, air fresheners, and automotive products. Other sources encompass building materials, office equipment, and craft materials.
TVOCs have been linked to eye, nose, and throat irritation, breathing difficulties, nausea, and damage to the central nervous system and organs such as the liver. Some TVOCs are classified as human carcinogens.
The researchers highlight the chemicals dimethylacetamide (DMAc) and dimethylformamide (DMF) for their connection to liver and reproductive damage.
The study’s limitations are acknowledged, including its small sample size and the exclusion of popular disposable masks like KN95s.
The study builds upon previous research suggesting potential drawbacks of mask-wearing. The Cochrane Institute research, for instance, suggested masks had minimal impact on Covid infections and deaths. Harms from masks, including disruptions to schooling, were not comprehensively evaluated.
The study also suggested that mask-wearing might elevate the risks of stillbirths, testicular dysfunction, and cognitive decline in children. However, critics highlight insufficient evidence for such conclusions.
Dr. Fischer cautions against drawing definitive conclusions, comparing potential mask side effects to medication side effects.
While the study was published in April, its findings could gain relevance as the Covid variant BA.2.86 spreads in the US, which is causing a mask mandate in some areas again.
However, the newfound concerns regarding masks’ protective types could challenge the effectiveness of mandates.
Dr. Fischer urges balanced policy-making, acknowledging the persistent presence of Covid and emphasizing policies that protect society without undue fracture.