The River Mersey is more polluted than the Great Pacific Garbage Patch – the largest accumulation of ocean plastic in the world. Greenpeace research shows the extent of plastic pollution in the UK’s rivers. The analysis, by Greenpeace scientists at the University of Exeter found microplastics were in 28 out of 30 locations in the UK’s rivers.

The worst site of all was the River Mersey – where a total of 875 pieces of plastic were found in just 30 minutes. Greenpeace uncovered 108 pieces of plastic in the Thames, making it the second most polluted river of the 13 examined. Next came the river Aire in Yorkshire, with 63 pieces, followed by the Severn at 42 pieces and the Trent, with 35 pieces, according to the study.

This means that the River Mersey is more polluted than the so-called Great Pacific Garbage Patch – the world’s largest accumulation of ocean plastic, which lies between Hawaii and California. Stretches of the Mersey contain up to six times as many pieces of plastic per square kilometre as the notorious garbage patch. Greenpeace said the particularly high level of plastic in the Mersey could be related to the giant plastic ‘nurdle’ making factory next to the river – operated by plastics firm Basell Polyolefins UK. The organisation said another factor could be the river’s proximity to large numbers of people in Liverpool, Manchester and Warrington. Microbeads – which have actually been partly 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, called the study a “wake-up call” for the government. She wants to see bold new plastic reduction targets in the upcoming environment bill, and aim to at least halve single use plastic production by 2025.

This study has discovered that the River Mersey is even more polluted than the Great Pacific Garbage Patch. A spokesman for LyondellBasell, which owns Basell Polyolefins UK, was reported to say that they take the global, complex issue of plastics in the environment very seriously and that they are doing everything possible to minimize and prevent their materials from inadvertently entering the environment.