Images of turtles trapped in plastic packaging or a fish nibbling on microfibres pull on the heartstrings. Yet many scientists studying plastics in the oceans remain open-minded on the longterm effects. While plastics shouldn’t be in our oceans, they say there is still insufficient evidence to determine whether microplastics – the very tiniest plastic particles, usually defined as being less than 1mm in diameter – are actually harmful.

On top of this, there is debate over how much plastic is actually in the sea and why so much of it remains hidden from view. Much of the research carried out to date is in its early stages – and has so far produced no definitive answers.

‘My concern is that we have to provide the authorities with good data, so they can make good decisions,’ says Torkel Gissel Nielsen, of the Technical University of Denmark (DTU). ‘We need strong data – and not just emotions.’