A study by the Yarra Riverkeeper Association found about half the litter in the river was expanded polystyrene
On a two-kilometre stretch of the Yarra River east of Melbourne’s CBD a few years ago, volunteers were gathering rubbish from the banks and reeds.
Among all the discarded bottles and bits of plastic sucked up with an oversized vacuum were an estimated 5 million pieces of expanded polystyrene – some in the form of tiny white balls, others in chunks at various stages of disintegration.