A more just society, a better recycling system, lower unemployment – Sweden is often upheld and much envied as a paragon of social and environmental stability. And now it looks as if they might have come up with a solution for the growing problem of microplastics too.
Microplastics, tiny plastic pieces and particles, are increasingly finding their way into our oceans and our drinking water – whether it’s through toothpaste, cosmetics or plastic particles that are shed from clothes made from artificial fibres when we do laundry. And because the pieces are so small, they can easily pass through water filtration systems and end up in our oceans and lakes, where they’re eaten by fish and end up in our food chain.
As part of the program “Cleaning Litter by Developing and Applying Innovative Methods in European Seas” (CLAIM), researchers from the Royal Institute of Technology (KTH) have now found a way of breaking plastic pieces down into CO2 and water using a process called photocatalysis.
The Nanotechnology Nailing Microplastic
How does the process work exactly? Well, it’s all based around the fact that plastics degrade when exposed to the sun – in a process called “photocatalytic oxidation”. When it happens naturally it takes a long, long time – and even longer when the plastics are under water, which sunlight has difficulty penetrating.
That’s why this team of sientists is testing a system of filters coated in a material madeup of nano-sized semiconductors that initiate and speed up this natural process. The microplastic – which is first filtered out of the waste water – then comes into contact with the semiconductor and under the influence of ultraviolet light and oxygen, is broken down into harmless CO2 and water via photocatalysis.
The researchers hope that their findings will be able stop more microplastic ending up in our waterways. “
These plastics will start accumulating in the food chain, transferring from species to species, with direct adverse consequences to human population,” said Joydeep Dutta from the KTH. “Tackling plastic pollution at its source is the most effective way to reduce marine litter.”
After the trials have been completed, the microplastic filters are set to be installed in the outlets of sewage treatment plants.
Micro or Macro: No Plastic Should Be in Our Waterways
The longterm goal of the CLAIM program is however a much larger move to tackle all kinds of plastic particles in our waters. We’re set to see more anti-plastic devices in the future – alongside this new filter system – including floating booms at the mouths of European rivers to collect larger plastic pieces.
The programme is coordinated by the Hellenic Centre for Marine Research (HCMR) in Greece and is financed with a Horizon 2020 Innovative Action grant from the EU Commission. The project started in November 2017 and will be running until the year 2021.