What do we do about PPE waste?

Photo Credit: Adobe Stock/Igor

Sometimes the solution to a problem can cause other problems down the road. To date, the COVID-19 pandemic has claimed some 6.5 million lives, a number that would probably have been a lot higher but for the personal protective equipment (PPE) worn by billions of people that helped slow the spread of the virus. But these PPEs have produced a crisis of a different sort: all the surgical masks, N95 masks, gloves, and other single-use items that have been thrown away.

Since the onset of the crisis in early 2020, demand for PPEs both within and beyond the health sector has skyrocketed. Each month from March 2020 to March 2022, an estimated 129 billion face masks – three million a minute, or 50,000 every second – and 65 billion gloves were used worldwide by healthcare workers and the general public. Other PPEs include surgical gowns, hair and beard nets, shoe covers, plastic wrap, shields, sheeting, sanitizing equipment, garments, test kits, and more.

PILING ON

All of this translates into an almost unbelievable amount of waste, virtually all of it containing plastic. One study shows that more than eight million tons of pandemic-associated plastic waste have been generated globally, with more than 25,000 tons entering the global ocean. In Canada, meanwhile, an estimated 63,000 tons of COVID-19 related-PPE ended up in our landfills between June 2020 and June 2021, with a smaller portion being incinerated due to biomedical contamination. Most disposable PPE is designed for single-use applications and consist of petroleum-based, non-biodegradable polymers. Disposable masks, for instance, may feel like soft cotton, but they’re almost all made from non-biodegradable material such as polypropylene (PP). PPE waste like masks escapes waste streams to become litter in a variety of ways, mainly either by being flushed down the toilet or simply discarded on the street. From there, it gets flushed into storm drains, many of which empty straight into streams, lakes or the ocean, adding to the already serious problem of microplastics and other plastic litter found in oceans and on land. Which is why the scientists behind the statistics predict that, by the end of the century, almost all pandemic-associated plastic litter escaping the waste stream will end up on the seabed or beaches.

Even when PPE waste is disposed of properly within the waste stream, the results aren’t ideal. In most jurisdictions, the stream coming from hospitals and long-term care facilities is deemed Category B waste – tainted by infectious substances – which means it can’t be sent through municipal recycling facilities. Nor can PPEs be recycled through mainstream or curbside recycling programs because the recycling process is so complex; in most municipal systems – which combine physical and biological processes – there is no way to separate the mixture of polymers contained in these products

Instead, the vast majority of PPE disposed in the Canadian healthcare system, and most other systems, is treated as non-dangerous general solid waste, and ultimately landfilled. The remaining fraction is treated as biomedical solid waste and is either disinfected and landfilled or incinerated. But these have their own drawbacks. Landfill sites have existed for decades all over the world, of course, but the rubbish buried in them decomposes very slowly, making them a problem for future generations; and landfills produce secondary side effects as well, including methane emissions, unpleasant views, and rat and seagull infestations which create their own waste problems. And many countries – Canada and the U.S. included – do not handle all of their recycling and waste domestically, instead shipping tonnes of waste overseas. Incineration, meanwhile, produces climate-warming carbon emissions, and also releases toxic air pollutants such as dioxins, furans, mercury and polychlorinated biphenyls into the atmosphere; there’s also just too much of the litter – hospitals in Wuhan, China alone burned through 240 tons of single-use PPE every day at the height of the pandemic and barely made a dent in the influx.

A LOW PRIORITY

Unlike the outbreak of the pandemic, the accumulation of PPE waste was predictable. Even as they mandated mask-wearing, governments all over the world were aware that the discarded masks and other PPE waste would accumulate very quickly, but at the outset of the pandemic, as institutions scrambled to carry out measures to protect overwhelmed healthcare systems from collapse, initiatives to deal with this waste weren’t prioritized. Now however, enough time has gone by – and enough discarded masks have been seen blowing around parks and city streets and floating in rivers and seas by enough people – for the problem to gain prominence, with growing calls to develop policies, programs, and innovations to safely reduce these primarily plastic items. But there are difficulties. First, even before the pandemic, the treatment of plastic waste wasn’t keeping up with the increased demand for plastic products, and post-pandemic PPE litter has added immeasurably to the problem – waste management and handling systems have limited capacity designed primarily based on pre-COVID patterns of biomedical waste generation. Pandemic epicenters in particular struggle to process the waste.

And second, because of its multi-material structure and potential contamination by bio-hazards, waste PPE isn’t currently recycled using such conventional mechanical recycling technologies as grinding, washing, separating, drying, re-granulating and compounding.

So, two years after the WHO officially labeled COVID-19 a pandemic in March 2020, and many tons of accumulated PPE pollution later, what do we do with all of this waste? We start with the realization that, while posing some challenges, reusing PPE is actually a huge area for growth. In Canada as elsewhere, government agencies, universities, and private sector firms are collaborating on an array of initiatives aimed at implementing recycling initiatives and developing reusable options for PPE.

FIRST OUT OF THE GATE

In February 2021, Canada’s first recycling program for single-use masks and respirators was launched in long-term care and urgent care facilities across Vancouver. The program was created through a partnership between Vancouver-based medical supply maker Vitacore Industries Inc., McMaster University in Hamilton, Ont., and the University of British Columbia, and provides PPE recycling bins at long term care and urgent care facilities at no cost. Once collected, the PPEs are sterilized by Vitacore before being sent to McMaster to be broken down and repalletized into polypropylene for use as construction materials to reinforce concrete or siding for buildings. And McMaster researchers are looking into ways to expand the possible uses for the repelletized materials. “The PP used in most masks and respirators is of very high quality, so it’s worth trying to recapture, and we’ve been able to divert a significant number of PPEs from landfill or incineration,” said Vitacore president Mikhail Moore. “One challenge to recycling PPEs is separating the various materials, such as aluminum from PP in masks, and we’ve created an automated process to do that.” A second recycling challenge, Moore continued, is to remove pathogens. “We know what type of PPE, and what type of plastic, we’re receiving in collected PPEs from hospitals, but we don’t know what type of pathogens or other bio-contaminants soiling there might be,” he said. “Going through a sanitation protocol to remove those pathogens is a very important part of PPE recycling. The catch at this point is that the sanitization process degrades the polymers slightly, but that step is being refined and we’re getting to the point where our end product is comparable to other recycled polymers that are suitable for non-medical, non-food contact applications.”

Also in 2021, Brantford, Ont.-based chemical recycling firm GreenMantra Technologies Ltd. received $300,000 from the federal government to develop solutions for efficient and cost‑effective recycling of disposable PPE waste. GreenMantra said it will take single-use PPE from Canadian hospitals as a feedstock and use a proprietary process to heat the material in the presence of a catalyst to produce waxes and specialty polymers. The company said its process produces specialty polymers that can be used as additives in construction materials like asphalt, roofing shingles, drainage pipes and plastic lumber, replacing fossil fuel-based additives. “The goal is to develop a stream of feedstock that can be used within our existing and future commercial-scale advanced recycling facilities,” said Domenic Di Mondo, chief commercial officer. “This will be on the scale of millions of pounds per year of diverted PPE with the potential to increase to tens of millions of pounds.” The grant is part of a federal program, called Innovative Solutions Canada, to invest in solutions to challenges from the pandemic, in this case, large amounts of hard-to-recycle PPE such as medical masks, surgical gowns and respirators made with plastics.

TERRACYCLE TUNES IN

Waste management company TerraCycle, headquartered in Trenton, N.J., has been involved in recycling PPEs since long before the pandemic, and has been offering its Zero Waste Box recycling solution – where people can drop off single-use PPE items such as gloves and face masks – since the early days of the crisis. The boxes can be found in numerous public spaces and shops throughout North America and the UK; and in Canada, authorities in the Quebec cities of Vaudreuil-Dorion and Pointe-Claire have set up boxes at various locations, as has Humber College at its North and Lakeshore campuses in Ontario. When full, the boxes are returned to TerraCycle for processing and the collected PPE waste is first aggregated before being cleaned and melted into pellets. The resulting recycled pellet material can then be used by third-parties to manufacture a variety of new products including outdoor furniture, plastic shipping pallets, outdoor decking, watering cans, storage containers, bins, and tubes for construction applications. According to TerraCyle president and CEO Tom Szaky, different programs are in place to sort different types of PPEs into different waste streams for different recycling processes for different end-products. “The face masks, which are primarily PP, can be reduced to a material that can be used for extrusion products, plastic decking, for example,” he said. “Elastomers, meanwhile, are ground down and then mixed with recycled plastics as an additive to provide a flexibility in an end-product. With plastic latex gloves, we separate the latex and nitrile – because those two materials are hard to mix together – and the end materials can go into flooring applications. The metals in the nose strips, which require magnets for separation, are used in barstock or metal sheeting.”

According to Szaky, approximately 90 per cent of TerraCycle’s PPE recycling uses mechanical recycling – which is the process of reducing plastics waste into secondary raw material or products without significantly changing the chemical structure of the material – with the rest being chemical recycling, which does change the chemical structure by turning plastic polymers back into individual monomers for repolymerization. Some regulations dictate what the Zero Waste Box program can and cannot collect, he continued, but otherwise the company works out its protocols on its own with its clients. “Mainly, we’re not allowed to collect PPE from a hospital environment because of contamination issues,” he said. “Other types of contamination are non-COVID-related but facility-related instead, and in these cases we work with the facilities to understand what those contaminants are – for example, paint from a body shop – and then we put protocols in place for that particular situation and that type of contamination.”

ALL ABOUT PYROLYSIS

TerraCycle’s reliance on mechanical recycling for PPEs is common among PPE recyclers, but there is some momentum growing behind a type of chemical recycling called pyrolysis, which is a waste-to-energy temperature reaction that reduces PPE to chemicals, resins, oil, propane, ethylene, and other fuels, and which involves no incineration or landfill use. Researchers at Cornell University, for example, are initiating a pilot project in New York state that will collect waste PPE from hospitals and medical centres and then send it to pre-processing and decontamination facilities in New York or Suffolk counties. There, it will be shredded, sterilized, and dehydrated to become small particles, and then brought to an integrated pyrolysis plant, like one contemplated for Rockland County, north of New York City. According to the researchers, the medium-temperature pyrolysis – about 1,200 degrees F – can deconstruct the plasticized gowns and gloves, which are derived from petroleum, into chemicals such as ethylene, butane, gasoline, bauxite, propene, propane, diesel, light naphtha, and sulfur.

Using a different principle, meanwhile, a team from Swansea University in Wales has developed a process that breaks down the plastic in PPEs into hydrogen using only sunlight. Photoreforming uses nanostructured semiconductors and light to degrade the plastic and any virus attached to it. The byproducts are hydrogen and chemical feedstocks, which can be reused by the chemical industry. No greenhouse gases are produced, the researchers say, and the process is cheap and easy enough to be used by rich and poor countries alike. Research is still at an early stage, but the researchers see the technology as a way to tackle disposable face masks and other hospital waste.

STRUCTURAL CHANGES

As of the fall of 2022, the worst of the pandemic seems to be behind us and it seems clear already that COVID-19 was the primary catalyst for short-term and long-term changes in plastic waste management systems and technologies. In some cases, the jury is still out on these changes. “In Europe and North America, new recycling players are getting into the PPE business, but the important question is, how consistent is the supply and can you build a stable business from it?” said Tom Szaky. “TerraCyle had a facility and process in place before the pandemic, and the pandemic doubled our supply, but we don’t know how long this boost is going to last. I think the levels of PPE being available for recycling will come down as demand for PPEs fall, but probably not to the level of before – we had baseline growth before the pandemic anyway, and going forward a certain percentage of people will decide they feel more comfortable wearing masks in public for good.”

And while PPE usage might decline, there still remains a massive amount of waste products going unrecycled, even now. “It’s estimated that about 99 per cent of PPE waste is still going to either landfill or incineration,” Mikhail Moore said. “It’s a very big problem – our program was able to recover 33,000 kilograms last year, which is the equivalent of 8.8 million masks. This is a good start, but the global is immense, both in Canada and globally.”

In the bigger picture, even before the pandemic, an estimated 77 million tonnes of plastic waste were being mismanaged annually; by contributing further to the challenge of managing municipal waste properly – especially in developing countries where resources and infrastructure are largely lacking – COVID-19 has forced the world to reckon with the gaps and neglected aspects of the waste stream and how we produce, use, and discard of our health care resources, from cradle to grave.

But this is why another legacy of the pandemic might be a more efficient plastics recycling sector, resulting from both large-scale government investment in recycling infrastructure contained in recovery packages and recycling companies’ own streamlining. “What PPE related to COVID shows us is that certain waste streams will index up and down, as opposed to traditional plastics recycling, which is good at creating baseline infrastructure but not at being malleable to ebbs and flows,” Szaky said. “So, I hope that one of the muscles that gets developed  is the ability to grow a supply chain and then reduce it when necessary.”