In short, it is an offence to buy Oxalic Acid without a £39 licence under the amendment to the Poisons Act, enforceable by the Police. It's also an offence to use it as a bee veterinary medicine under the Veterinary Medicines Regulations (enforceable by the the NBU) as well as an offence under the Poisons Act if used without a licence with enforcement again by the Police.
That's clear but what is not so obvious is whether Apibioxal, which is about 90% Oxalic Acid, will require a £39 Poisons LIcence to purchase and use - there does not appear to be an exemption in the new regs for products like Apibioxal.
This appears to be a typical case of the left hand of government not knowing what the right hand is doing. It would be a real b*gger if, because of the new poisons regulations, the NBU had to withdraw the Apibioxal approval or require beekeepers to buy a £39 licence to buy the stuff after the recent fanfare of its approval.
Trouble is, if you don't know the answer you're likely to get, it's probably not a good idea to ask the question!
CVB