A pollutant that killed thousands of birds off the coast of Britain earlier this year will no longer be dumped at sea after a worldwide ban was agreed.
More than 4,000 birds were killed or injured by the chemical polyisobutene (PIB) between Cornwall and Sussex, and on the Channel Islands.
The International Maritime Organisation (IMO) has reclassified PIBs from 2014.
It means ships will only be able to wash their tanks and dispose of all PIB residues while in port.
Until now it has been legal for discharges to be made when vessels wash out their tanks, as long as they are further than 12 nautical miles from the nearest point of land.