31 July 2024
For several months, the media have been reporting that the small single-use blue masks that have invaded our faces and our environment are washable up to 10 times, while many are already using the same one over and over again for weeks or even months. Yet, due to the reduced filtering power of disposable masks on the fine particles (the most hazardous), and the plastic microfibres they release over time, wearing them more than a few hours or, worse, putting them in the washing machine is very risky for both people and the environment. Explanations.
By Antoine Palangié *
Washing disposable masks will have no health benefits for humans or the planet, on the contrary. That’s due to the process implemented to ensure the essential of their filtering power that does not stand water; the same defect limits their useful life in full capacity to a few hours: disposable, they are therefore for good reason, unfortunately.
Being able to reuse them would be excellent news, however, as 130 billion of these single-use medical procedure masks – their official name – end up every month scattered in nature and landfills. Since the beginning of the pandemic, about 3,400 billion have been consumed. That’s enough to make… 17,000 times around the Earth, more than twice the round trip to the Sun.
Because they are made of almost-eternal plastic fibres, talking about an ecological disaster grafted to the health crisis is not exaggerated. And it becomes tempting to hope for miracle solutions. But the reality on the ground is, once again, more complex than that of the effects of media announcements.
Never without my charge
Disposable medical procedure masks ‘’cheat’’: they owe most of their filtration capacity to an artificial electrostatic barrier. Basically, their synthetic fibres are charged with static electricity before leaving the factory, allowing them to act as miniature magnets on the particles emitted by the wearer’s exhalation, and those present in the air it inspires (the aerosols).
Without this power of attraction, single-use masks are in fact a poor means of protection of the wearer as well as of his surroundings, since poorly formed on the face and therefore very poorly sealed. In other words, they leak all around and limit only very little outward dissemination and inward penetration of particles if they do not “magnetize” them to their fibres.
The problem is that this electrostatic barrier is deleted by water. This is in essence the reason why these masks are disposable after just 3 or 4 hours: the moisture of the wearer’s breath dissipates the electric charge, and thus this ability of the mask to behave like a magnet.
A fortiori, washing a disposable mask, even once, brings it back to what it is basically without its electrostatic charge: a banal piece of synthetic fabric poorly stretched and poorly adjusted in front of the nose and mouth.
Whether one wears a disposable mask for too long or washes it, the result is the same: a protective capacity much lower than that of the same new mask, and very insufficient in the absolute.
A trap too coarse
Proponents of reuse argue that the fabric itself of a disposable mask washed up to 10 times remains tight enough to retain particles of 3 microns or more. That is enough to comply with the EN 14683:2019 standard governing medical masks, explains the scientific publication behind this concept of single-use mask washing1.
But this is a very fragile achievement in the face of the current pandemic. Although the 3-micron limit guarantees protection against bacteria, it has virtually no effect on viruses, which are much finer. For example, the COVID-19 virus is about 30 times smaller in diameter and 27,000 times smaller in volume.
In addition, the current pandemic has changed the understanding of how respiratory diseases are transmitted: it is now known that it occurs first via aerosols, extremely fine particles floating in the air (nanoscale or submicron particles, i.e. of a size below the micron)2, much smaller than those previously considered to be vectors of pathogens, such as sputters or spits. And all this is even before considering the problem of the very poor sealing of the disposable medical mask.
Polluting to its core
Finally, and this is also crucial, disposable masks release large quantities of non-biodegradable synthetic fibres into the environment, which are highly suspected of deeply disturbing aquatic ecosystems3.
With stirring, rubbing, exposure to hot water and chemical agents, washing disposable masks worsens the intensity of this microplastic pollution by accelerating wear and detachment of fibres.
Do not throw any more!
With the introduction of rigorous standards on reusable masks such as the F3502-21 from the prestigious American Society for Testing and Materials, and the latest arrival of highly reusable medical washable masks, some thoroughly-tested and compliant products now offer effective and eco-efficient alternatives to single-use respiratory protections.
It is also time to learn from the early days of the pandemic, marked by an extreme shortage of disposable masks, by stockpiling these new washable masks. Because in addition to the serious deficiencies exposed above, it should be known that disposable masks lose their electrostatic charge even as new inside their packaging, which limits their shelf life to a few months.
It is therefore towards these new sustainable solutions that the choices of decision-makers and buyers, R&D efforts, must now be directed in the context of a never-ending pandemic, and in the longer term with a health system where single use remains the norm and threatens global environmental protection commitments.
(*) Antoine Palangié is an environmental research engineer, journalist and scientific consultant. Since the very beginning of the COVID-19 pandemic, he has worked as an expert on sustainable, breathable and effective filtration media development projects to fight the proliferation of disposable masks. He is the Scientific Director of FRËTT SOLUTIONS, the first company worldwide to offer medical and N95 masks washable more than 100 times in a simple domestic machine.
(1) https://dx.doi.org/10.1016%2Fj.chemosphere.2021.132364
(2) https://doi.org/10.1016/j.jaerosci.2021.105914
(3) https://ici.radio-canada.ca/nouvelle/1830698/masques-jetables-microplastique
