The heartbreaking effect of human waste was discovered when a post-mortem was conducted on 13 beached sperm whales.

The plastic we discard into the ocean often makes its way into the mouths and stomachs of sea creatures.

A post-mortem of the creatures, found ashore near the town of Toenning in Schleswig-Holstein, Germany, showed their stomachs were full of plastic.

This plastic included a 13-metre-long (43-foot-long) fisherman’s net and a 70-centimetre (28-inch) piece of plastic from a car.

A man posted a shocking image on Instagram of some of the plastic found in their stomachs.