Studies estimate worldwide humans are using 129 billion face masks each month. Most masks are disposable, made from plastic microfibers that are not biodegradable and may fragment into smaller plastic particles polluting ecosystems.
The high demand for face masks since the coronavirus pandemic began has resulted in the production of billions of disposable masks — with no way to properly dispose of them.
Masks are littering cities, clogging sewage channels and turning up in bodies of water, prompting researchers to warn of the potential for masks to become the next “plastic problem.”
Recent studies estimate that worldwide, humans are using 129 billion face masks each month — about 3 million a minute. Most of them are disposable face masks made from plastic, non-biodegradable microfibers that break down into smaller plastic particles — micro- and nanoplastics — that become widespread in ecosystems.
The World Health Organization says an estimated 89 million medical masks are required for the COVID response each month, a trend likely to persist for some time.
At the start of the outbreak, U.S. officials estimated the country would need 300 million face masks to cope with the pandemic in 2020. U.S. manufacturer 3M made 550 million masks in 2019 and plans to produce 2 billion this year as long as the pandemic lasts.
“The enormous production of disposable masks is on a similar scale as plastic bottles, which is estimated to be 43 billion per month,”said environmental toxicologist Elvis Genbo Xu from the University of Southern Denmark, and professor Zhiyong Jason Ren, an expert in civil and environmental engineering at Princeton University. “But unlike plastic bottles, there is no way to recycle face masks, making them more likely to be disposed of in inappropriate ways.”
Common surgical masks have three layers: an outer layer with non-absorbent fibrous material (like polyester) that protects against liquid splashes, a middle layer with non-woven fabrics (like polypropylene and polystyrene) created using a meltblown process which prevents droplets and aerosols via an electrostatic effect, and an inner layer made of absorbent material like cotton to absorb vapor.
Masks contain many polymers, including fabric polypropylene. Polypropylene is one of the most commonly produced plastics and does not easily break down. Weathering from solar radiation and heat cause polypropylene to generate a large number of micro-sized polypropylene particles and nanoplastics.
Disposable face masks are made directly from microsized plastic fibers, which release plastic particles easier and faster than bulk plastics like plastic bags. A newer generation of masks, called nanomasks, releases even smaller particles creating a new source of nanoplastic pollution, according to the University of Southern Denmark.
Like other plastic debris, “disposable masks may accumulate and release harmful chemical and biological substances, such as bisphenol A, heavy metals and pathogenic microorganisms,” according to Xu and Ren. Some of the toxic chemicals released during degradation of plastic polymers include phthalates, organotin, nonylphenol, polybrominated biphenyl ether and triclosan.
The impacts of plastic as a solid waste and microplastics contamination in the environment have been investigated, validated and demonstrated by different researchers in various publications, according to a study in Marine Pollution Bulletin.
Face masks get into the environment when disposed in landfills and dumpsites or littered in public spaces. They then make their way into lakes, rivers and oceans, breaking down into plastic particles within a few weeks.
In the years prior to the pandemic, environmentalists warned about skyrocketing plastic pollution and its threat to oceans and marine life. As much as 13 million tons of plastic ends up in our oceans every year, according to a 2018 estimate by UN Environment.
According to a report by OceanAsia, roughly 52 billion face masks were manufactured in 2020 to meet the demand of the coronavirus pandemic and 1.56 billion were estimated to have entered the ocean, resulting in 4,680 to 6,240 metric tonnes of face masks. These masks take as long as 450 years to completely break down –– slowly turning into microplastics that negatively affect marine wildlife and ecosystems.
The environmental research community needs to move faster to understand and mitigate these risks, said researchers Xu and Ren. They proposed the following for dealing with the problem:
Set up mask-only trash cans for collection and disposal. Do not put masks in the recycling.
Consider standardization, guidelines and strict implementation of waste management for mask wastes.
Replace disposable masks with reusable face masks like cotton masks.
Develop biodegradable disposal masks with materials that are safe.