Discarded chewing gum and old fridge parts are to be recycled in an Edinburgh-led initiative to improve sustainability in the healthcare sector.
Both materials will be repurposed to help cut the carbon footprint associated with the manufacture of disposable medical testing kits.
The bid to mass-produce lateral flow tests (LFTs) without using fossil fuels involves researchers from the University of Edinburgh and Heriot-Watt University.
Social scientists at Edinburgh, whose research highlights the global impact of LFT waste, have teamed up with biomedical engineers at Heriot-Watt to devise solutions.
Researchers at Heriot-Watt's Global Research Institute in Health and Care Technologies have produced five prototype devices made from a range of emerging plastic materials.
Familiar problem
The first is discarded chewing gum collected by Gumdrop - a company founded to tackle this familiar problem on city streets.
Gumdrop recycles the waste into a product called Gum-tec, which can be used in place of conventional rubber and plastic compounds.
The second sustainably derived material derives from old fridge parts made from High Impact Polystyrenes, which are 100 per cent recyclable plastic.
The other three prototypes are made from Limex, a material derived from limestone; Terralene, a bio-compound based on polyethylene; and a biodegradable and compostable plastic called Bio-flex.
Growing market
It is estimated there are over four billion lateral flow tests manufactured annually and the market is set to grow from $43 billion in 2022 to $72bn by the end of 2024.
Around 16,000 tonnes of plastics are produced globally for rapid testing every year with an average test containing 10-15g of first-use plastic.
LFTs entered the public consciousness during the Covid pandemic but are used to identify a range of illnesses and conditions.
Together with disposable masks, they have been a visible part of the growing problem of medical waste.
Very few of the plastics used in medical testing are recycled - partly because of potential contamination - and most of it is sent to incineration or landfill.
Key role
Professor Alice Street, of the University of Edinburgh's School of Social and Political Sciences, says: "LFTs are used globally for a growing number of diseases and are especially important in low-resource settings but not enough attention has been paid to the plastic waste they generate."
Professor Maïwenn Kersaudy-Kerhoas, an expert in microfluidic engineering based at Heriot-Watt, says: "If we can make LFTs out of sustainable materials and without the use of fossil fuels, then we can save between 30 and 80 per cent of carbon emissions that virgin plastic processing produces."
The sustainable LFTs project is part-funded by the DIADEV project - Investigating the Design and Use of Diagnostic Devices in Global Health.
DIADEV is funded by the European Research Council under the European Union's Horizon 2020 research and innovation programme.
