If you drop plastic in the ocean, where does it end up?

Modelling shows that ocean currents can concentrate slow-degrading debris in certain parts of the world's oceans, leading to so-called 'garbage patches'

It is estimated that between four and 12m metric tonnes of plastic makes its way into the ocean each year. This figure is only likely to rise, and a 2016 report predicted that by 2050 the amount of plastic in the sea will outweigh the amount of fish.

A normal plastic bottle takes about 450 years to break down completely, so the components of a bottle dropped in the ocean today could still be polluting the waters for our great-great-great-great-great-great-great-great-great-great-great-great-great-great-great-great-grandchildren.