what we know about kids and masks

when a new medical story breaks, it tends to get lots of attention. but when that new piece of research gets disproved, the retraction makes almost no impact. that was the case recently with the retraction of a study in jama pediatrics that suggested that mask wearing was dangerous in children. its publication fuelled some of the anti-mask, anti-covid sentiment that lingers in our society and needlessly spread fear among parents.it was, however, ultimately untrue.the study, if you did not hear about it, purported to show that wearing face masks was dangerous for children because it increased the amount of carbon dioxide they were breathing into their lungs. studies about the theoretical dangers of face masks have been rampant throughout the pandemic, and early on many people who were opposed to mask wearing claimed that it would deprive the wearer of oxygen and impede lung function. in fact, this was easily disproved by scientific research in older adults showing no reduction in oxygen levels while wearing a mask. there is also the obvious fact that many people wear surgical masks for long periods of time without keeling over and that doctors wear surgical masks for hours at a time in medical settings without any ill effects.this most recent study took a different tack and claimed harm, not in adults, but in children. parents are understandably more worried about their children than they are about themselves, and someone willing to disregard misinformation about mask use in adults might be susceptible to a news story claiming harm to their kids. but many doctors and researchers who read the study when it was published almost immediately saw that it was fatally flawed.the authors measured carbon dioxide levels on the inner surface of masks while being worn by 45 children aged six to 17. they found carbon dioxide levels to be what they claimed were dangerously high and possibly toxic. but there were some irredeemable problems with the study. first, the device they used to measure co2 levels was designed to measure co2 levels in incubators and had a large margin of error when used in an open setting.many researchers who study exposure medicine commented on the paper and questioned whether this device was appropriate. also, the study measured co2 levels in the pocket of air inside the face masks of children. but that did not accurately reflect how much co2 was actually entering their lungs because the inhaled air would have been a mixture of that tiny air pocket and the ambient air around them, which would have had very low levels of co2 in it. more worrying though is that the lead authors had recently published another paper claiming that covid vaccines killed two people for every three deaths prevented. this claim was patently absurd given that the streets outside vaccination centres are not littered with dead bodies and that paper was also retracted in short order.the problem with these studies is that even once retracted they are still used by people who oppose vaccines, mask use or any of the pandemic measures that we have put in place. people often continue to quote faulty research long after it has been contradicted by newer data, so much so that sometimes bad ideas sometimes simply do not die.this study was never taken very seriously by the medical community in the 16 days between publication and retraction. but someday, someone might come up to you and claim that masks are dangerous for children (halloween not withstanding). they might vaguely refer to a study that showed co2 levels rise in kids who wear masks. now you can confidently tell them that that study was actually retracted because it had critical methodological flaws. i don’t know if it will work but it just might be enough to change someone’s mind.christopher labos is a montreal physician.