Greenpeace is calling for "bold" plastic reduction targets after a survey of 13 rivers found that all contained microplastics.
The latest research showing the extent of plastic pollution in the UK’s rivers found 1,271 pieces at points sampled along the Exe, Thames, Severn, Great Ouse, Trent, Mersey, Aire, Derwent, Wear, Conwy, Wye, Clyde and Lagan.
Analysis by Greenpeace scientists at the University of Exeter found microplastics were in 28 out of 30 locations.
The worst site was the River Mersey, where 875 pieces of plastic were captured in half an hour, making it more polluted than the Great Pacific Garbage Patch.
The Great Pacific Garbage Patch, between Hawaii and California, is the largest accumulation of ocean plastic in the world.
Microbeads, despite having been partially banned, were found in five rivers while seven rivers had plastic pellets known as nurdles.
And more than 80% of the polymers found were those used to make things such as food packaging, milk and water bottles and plastic bags.
Fiona Nicholls, ocean plastics campaigner for Greenpeace UK, said the study was a wake-up call for the government.
She added: Fiddling around the edges of the plastic pollution problem by banning straws simply doesn’t cut it.
We need to see bold new plastic reduction targets in the upcoming environment bill, and aim to at least halve single use plastic production by 2025.
Steve Backshall, wildlife expert and TV presenter, said: Plastic pollution isn’t just a domestic issue – its impacts are seen on wildlife and humans all over the world.
For the sake of nature and for the sake of future generations we need to stop producing so much of it – it’s the only way forward.
A spokesman for the Department for Environment, Food and Rural Affairs said: The UK is a global leader in tackling plastic pollution and is already making great strides – banning microbeads in rinse-off personal care products, taking 15bn plastic bags out of circulation with our 5p carrier bag charge, and announcing plans to introduce a deposit return scheme for single use drinks containers.
We know there is more to do, which is why we are funding ground-breaking research into how microplastics enter waterways and working with the water industry to find new methods to detect, measure and remove microplastics from wastewater.
:: Sky’s Ocean Rescue campaign encourages people to reduce their single-use plastics. You can find out more about the campaign and how to get involved at www.skyoceanrescue.com