INSURANCE companies have threatened legal action against the Scottish government if it passes legislation allowing asbestos workers who have not fallen seriously ill as a result of contact with the substance to sue for damages.

Last year, the House of Lords ruled that people with “pleural plaques” - a thickening of lung tissue caused by exposure to asbestos fibres - should no longer be able to claim compensation.

It ruled that because the plaques are not in themselves harmful and cause no physical symptoms, only anxiety, they do not merit damage payments.

Medical experts agree that although they are a “marker or litmus test” of asbestos exposure, plaques do not mutate into lethal forms of asbestosis, such as mesothelioma, which still merit damages.

Kenny MacAskill, the justice secretary, promised to introduce legislation at Holyrood reversing the ruling and setting Scotland apart from the rest of the UK.

He was supported by MSPs of all parties as well as Clydeside Action on Asbestos (CAA), the campaign group, and Thompsons Solicitors, which handles 90% of asbestos claims north of the border. Legislation is due to be tabled before the summer recess.

However, insurance companies have warned the bill would fundamentally change the law on damages in Scotland, allowing people to sue employers for “exposure only” to potentially harmful material, regardless of whether they suffered actual harm.

They claim it would “open the floodgates” to a raft of flimsy damage claims, pushing up premiums and costs for businesses.

In a submission to a government consultation on the proposed legislation, AXA Insurance said it was “wholly wrong and should not be progressed”, with a basis that was “flawed in many respects”.

The proposal “would create a wholly new entitlement to compensatory damages for conditions that do not give rise to any symptoms or increased risk of adverse health in the future”.

It estimated the 630 outstanding claims would generate about £4.5m damages, 90% of them handled by Thompsons.

Axa's spokesman added: “We must question the validity of any consultation process that is so clearly being supported by a major beneficiary of the decision to legislate.”

Zurich, one of the two lead insurers in last year's judgment in the Lords, said it was concerned about opening the floodgates to exposure-only claims, warning: “Zurich has already taken legal advice on challenging any proposed legislation.”

CBI Scotland, the employers' organisation, said the bill would undermine a “stable and principled legal framework that business and citizens can rely upon” in Scotland. However, the Faculty of Advocates, the legal body, said the bill was “both justified and reasonable”.

Frank Maguire, a senior partner with Thompsons, said: “Our efforts to help those suffering from pleural plaques is driven by principle, not profit.

“If anyone has a vested interest in denying pleural plaques victims their right to fair and just compensation it is the insurance companies, who will have to pay out on behalf of their clients.”

A government spokesman said: “The justice secretary has made clear his commitment to ensure that those who suffer the effects of asbestos as a result of our industrial past are able to claim for damages. The bill will bring some relief to people living with this condition.”

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