Growth hormones. It’s better now than some years ago, but still. Some claim the do not use them at all.
And they use a lot of antibiotics.
And there is some accumulation of dioxins and PCBs in the fat due to the feed, but this has also been approved somewhat.
>Some claim the do not use them at all.
It is against the law in most if not all EU countries. It is also the dispute between US and EU agriculture trade.
Compared to most other meat production farmed salmon does not use a lot of antibiotics