Salmon suffering at Scottish fish farms is “endemic” and in breach of animal cruelty law, according to an undercover investigation by animal welfare campaigners.
Nearly half of Scotland's salmon farms burn, dump or destroy millions of dead fish every year.
As farming of sea bass and sea bream has grown in Greece and Italy, so have environmental concerns.
Fish farmers in Scotland are permitted to use 16 "toxic" chemicals to kill parasites and fungi, control infections and anaesthetise fish.
Scottish Government research into pesticides used to control the lice that infest farmed salmon deliberately excluded impacts on the “wider marine environment”.
Six fish farming companies in Scotland given government handouts of over £10 million have made profits of £926 million since 2010.
The Scottish Government has reprimanded salmon farming companies for breaking the rules on shooting seals - but has not taken any further action.
The Scottish salmon farming industry has incurred “hidden” costs of £3.3 billion since 2013 because of deaths, pollution, parasites and poor animal welfare.
Fish farming companies are being allowed to breach environmental limits and pollute lochs because of export problems caused by Brexit.