Want to better avoid the new, more infectious strains of coronavirus raging across the United States? Cinch tight or double up on your face mask.
The Centers for Disease Control and Prevention said as much when it announced updated guidance earlier this month. While any mask is better than none, according to Dr. John T. Brooks, M.D., chief medical officer for the agency’s COVID-19 response and lead author of a new government study on masking, wearing a snug-fitting respirator-style mask or layering a washable cloth mask on top of a disposable medical procedure one — aka “double-masking” — can reduce a person’s potential exposure to pathogen-containing respiratory droplets by up to 96%.
Most of this advice comes down to improving fit: any gaps between your face and mask allow virus particles to slip in or out. But material matters, too. The same study showed that multilayer cloth masks block between 50% to 75% of airborne droplets — a significant amount of protection, to be sure, but nowhere near as effective as the first two options.
For those who have been eschewing disposables for environmental reasons, the dilemma of choosing between safeguarding public health and preventing plastic pollution can be a vexing one.
It’s a concern that isn’t without foundation, either. The United Nations estimates that 75% of single-use face masks, which are typically made of fossil fuel-derived polypropylene, ultimately wind up in the landfill — and that is likely the best-case scenario. Oceans Asia, an environmental group based in Hong Kong, estimates that more than 1.5 billion disposable face masks ended up in the world’s oceans at the close of 2020, resulting in an additional 4,680 to 6,240 metric tons of marine plastic pollution. This additional burden not only further endangers marine life but also contributes to the spread of tiny plastic particles known as microplastics, which have been detected in the bellies of deep-sea animals, at the peak of Mt. Everest, and in drinking water.
Masks can escape into the environment when they’re littered, otherwise improperly discarded, or when waste management systems are inadequate or overwhelmed, says Sam Cooke, a research associate at Oceans Asia. “A landfill is also not a particularly secure way of storage,” he adds. Because face masks can weigh a mere 3 grams, “things can get washed or blown away.”
Recent cleanup data from the Surfrider Foundation, an environmental nonprofit from California, uncovered more single-use masks than takeout containers at beaches across the country. “Takeout has been big during COVID, so comparing the two really puts things into perspective,” says Jennie Romer, legal associate for the organization’s Plastic Pollution Initiative.
Disposable face masks are not recyclable through most curbside recycling programs, though that hasn’t prevented well-meaning people from “wish cycling,” or putting a non-recyclable in the recycling bin on the off-chance it has another use, says David Biderman, the organization's executive director and CEO of Solid Waste Association of North America, a trade association for municipal waste management firms.
The organization’s members are “definitely seeing more face masks mixed in with the cardboard, plastic, cans, and other permitted recyclables, which can make recycling more difficult and expensive,” he says, noting an “epidemic of PPE litter” last year that saw many people tossing their masks and gloves on streets and in parking lots. “We urge everyone not to do this, and dispose of their masks properly — by placing them in a trash can.”
While Australian researchers suggest used face masks could be shredded up into road-paving materials, the idea is still in its early days with nothing definitive in the cards (same thing with biodegradable masks). Meanwhile, opting for reusable masks creates 85% less waste and generates a three-and-a-half times lower impact on climate change, according to one University College of London assessment.
Weighing all this against a global health crisis can make for some difficult choices, admits Dr. Peter Chin-Hong, M.D., an infectious disease expert and professor of medicine at the University of California, San Francisco. “I do recognize that I’m contributing to untold amounts of pollution and animal deaths,” he says. “On the other hand, we never faced such an unprecedented pandemic before in our lifetime. So I think, given that risk-benefit calculus, I would support wearing good-quality masks.”
That doesn’t necessarily mean double-masking all the time, however, Chin-Hong says. For non-elderly adults without preexisting conditions, a cloth mask is perfectly adequate for walking the dog, a grocery-store run during non-peak hours, or other low-risk situations. N95 and other respirator-style masks are only essential in a health care environment, where the odds of transmission are far higher. “It all depends on context,” he says.
Jill Crittenden, a research scientist at the Massachusetts Institute of Technology, recommends the use of what she calls “high-filtration” or “hi-fi” masks, which tests have shown screen out more than 90% of respiratory drops and particles. They’re better-fitting than surgical masks, more comfortable than N95s, and are in ready supply online. And although hi-fi masks are meant for single use, they don’t have to be one-and-done. As long as they’re not damaged or soiled, she says, they can be reused multiple times and still maintain their filtration prowess.
To stretch out their use, Crittenden recommends buying a few masks and storing each one in a paper bag for a week after use to kill off any wayward contaminants. (Sars-Cov-2, the virus that causes COVID-19, can’t survive on surfaces for longer than five days.) “So if you can afford to have seven masks labeled Monday to Sunday, and then use one per week, you can have a supply of seven that will last you several months,” Crittenden says.
When a disposable mask is unavoidable, environmentalists like Cooke recommend snipping off the ear loops before throwing it away in a trash can, much like you might do with eight-pack rings. This helps prevent marine animals from getting entangled if the mask makes it out to sea. Other ways of mitigating mask pollution are obvious: continue to socially distance, avoid large groups of people, and get the vaccine when it’s available to you.
Equally helpful is saving the big guns for occasions where they’re mandated or imperative. “Unless you’re in an area which really requires full protection, a cloth mask, especially if it’s washed, is going to be fine,” he says.