During 2019 Greenpeace undertook a tour of 13 UK rivers investigating plastic and microplastic pollution of rivers. They took samples from the follewing rivers : Clyde, Lagan, Wear, Derwent, Mersey, Aire, Conway, Trent, Wye, Severn, Thames, Exe and Great Ouse. After analysis plastic was found in all 13 rivers, with 800 plastic particles being found in just 30 minutes in the River Mersey samples.