UNDER pressure from farmers, the Scottish environment minister Ross Finnie is campaigning to exempt Scotland from a ban on a toxic chemical that kills wildlife.

He is demanding a decision by UK ministers to suspend marketing authorisation for sheep dips containing cypermethrin be reversed north of the Border.

But Finnie's stance has been condemned by angling organisations, who say that the chemical can be "devastatingly lethal". And the minister's campaign has not been fully endorsed by his own environmental watchdogs.

Farmers dip sheep in a chemical bath to rid them of scab, a debilitating maggot infestation which can kill. But if cypermethrin in the dip leaks into local burns, it can kill insects and fish.

An investigation in Wales last year by the government's Environment Agency uncovered 32 incidents in which leaking sheep dip had caused serious environmental damage. The 12 worst cases involved cypermethrin killing large numbers of insects and fish, and led to 10 farmers being prosecuted.

As a result, the Veterinary Medicines Directorate (VMD), which authorises the marketing of sheep dip, decided in February to ban cypermethrin until further notice. Scottish farmers claimed that the chemical hadn't been shown to cause similar problems in Scotland.

After the National Farmers' Union of Scotland met with the Scottish Executive last month, Finnie wrote to the VMD requesting a special "regional authorisation" for Scotland. "The Executive is supporting the efforts to have cypermethrin remarketed in Scotland, " the minister's spokesman told the Sunday Herald.

"It is a valuable treatment for sheep scab, which is a serious condition." The number of sheep dip incidents in Scotland had been at a "low level", he argued, and routine monitoring had not highlighted it as a "particular problem".

This is fiercely disputed, however, by angling groups like the Association of Salmon Fisheries Boards. The Executive was "turning a blind eye to the pollution impact of a devastatingly lethal chemical, " said the association's director, Andrew Wallace.

The kind of targeted monitoring of upland streams carried out in Wales had not been done in Scotland so problems had remained undetected, he argued.

"If the Executive is calling for the ban to be lifted in Scotland, then it is failing in its primary responsibility to protect Scotland's natural environment."

The Scottish Environment Protection Agency (Sepa) accepted that it had not investigated sheep dip pollution like the Environment Agency. "It is very difficult to be categorical that a problem does not exist due to the costs and practicalities of sampling on a wider scale, " said Rob Morris, Sepa's land policy manager.

"The evidence from our monitoring data does not conclusively support a ban in Scotland. However, we recognise that, with the ban in place, there is a reduced risk of pollution."

Sepa has recorded 24 cases of sheep dip pollution over the last five years, some of them significant and requiring enforcement action.

Scottish Natural Heritage (SNH), the government wildlife conservation agency, had "concerns" about the impact of cypermethrin. "There is certainly a clear need that any use of cypermethrin is carried out responsibly and that it is disposed of safely, " said an SNH spokesman.

The National Farmers' Union for Scotland (NFUS) agreed that cypermethrin was "jolly dangerous stuff" but only if used improperly, and insisted there was no evidence of misuse in Scotland.

Farms are monitored every four years by Sepa, and their management practices are audited every year under a quality assurance scheme, an NFUS spokesman pointed out.

"If there is a problem, show us the evidence and we'll deal with it. But please don't take away an animal welfare tool when there is no evidence because it will bring misery to millions of sheep."

NEED TO KNOW FACTS The Scottish Executive has backed a call to exempt Scotland from a UK ban on a chemical lethal to wildlife.

BACKGROUND Cypermethrin has been withdrawn in sheep dip, but can still be used by salmon farmers to kill lice.

NEED TO KNOW MORE?

http: //www. nfus. org. uk: National Farmers Union of Scotland http: //www. sepa. org. uk: Scottish Environment Protection Agency http: //www. snh. org. uk: Scottish Natural Heritage