Sustainable Industry

Disposing of disposable masks properly

Masks cannot be recycled as they are potentially contaminated. However, if thrown into the environment, they become a serious source of pollution

The Covid-19 pandemic compounded existing challenges by causing an unexpected problem: surgical masks that are recklessly thrown away. Unfortunately, all around the world, once used and thrown away, these protective items have become a source of environmental contamination and an additional threat to the lives of people and animals on land and in rivers and oceans. But how are masks supposed to be disposed of anyway?

Typically made from synthetic non-woven fabric (NWF), the masks recommended by public health authorities as most effective should be disposed of after a few uses and, unfortunately, cannot be recycled because they are potentially contaminated.

“Disposable masks are made from synthetic materials: although NWF is plastic fiber – a type of polymer –, when used in masks, it necessarily becomes waste,” says Fernanda Daltro, executive manager of Compromisso Empresarial para Reciclagem (Cempre), an association devoted to promoting solid waste recycling in Brazil. Fernanda reiterates that masks are not recyclable and can carry contaminants and that, therefore, they must be put in a tightly closed plastic bag and go to the regular trash bin.

Fernanda shares another caveat and gives an important tip. “Masks going astray in the environment are a source of plastic pollution, so they can lead to animals being killed: it is important to break the rubber bands so that they do not end up stuck in paws, beaks or mouths.”

Recommendations – Last March, the Brazilian Association of Sanitary and Environmental Engineering (Abes) published a booklet with recommendations for waste management in a pandemic.

According to the document, the most important thing is to remember that the disposable protective mask should never go to the recycling bin. Protective materials for patients in home isolation (and those who take care of them) must be disposed of in two resistant plastic bags – one inside the other. With the mask in the double plastic bag, without filling it excessively, you must close it tightly with a knot or seal and place it in the bathroom trash. The double bagging ensures enhanced protection at all stages of the journey of this waste – handling, collection, transportation and final destination – and reduces the risk of the workers involved getting contaminated. Furthermore, it prevents disposable masks from being diverted for possible reuse or thrown into nature.

After double bagging, if possible, it is best to label the bag and place a warning on it: “risk of contamination”. Thus, once closed and identified, the material is usually routed to municipal waste collection.

Microplastic – The major problem that is inherent to disposable masks is that, as with any other plastic, the synthetic material that goes into its production degrades and fragments into micro- or nanoplastic particles – one of the most serious environmental problems in the contemporary world. It is extremely difficult to remove microplastics from the environment and, therefore, they end up contaminating nature and threatening the lives of people and animals. How? Through the food chain. Many current studies attest to the presence of microplastics in fish and other everyday foods.

Pioneering research – All around the world, researchers are trying to find a solution for the reuse of disposable masks.

The microfibers in the masks can be useful in the concrete industry, for example. Today, it is common to add microfibers to cement concrete to strengthen it – to address microscopic cracks that could eventually lead to material failure – but these are costly.

In a recent paper (“Upcycling Waste Mask PP Microfibers in Portland Cement Paste: Surface Treatment by Graphene Oxide”) published in the scientific journal Materials Letters, researchers at Washington State University used disposable masks to enhance concrete and achieved a surprising result: a combination of cement and disposable masks is 47% stronger than regular cement after one month of curing.

While a solution is not found for the reuse of masks, however, it is important that everyone does their part so that this important protective equipment does not become yet another threat to the planet.