HIGHLY radioactive lobsters have been found in the Solway Firth off Sellafield nuclear reprocessing plant, Greenpeace claimed yesterday.

Levels of contamination in the crustaceans tripled in two years, said the environmental group, and are so high that had they been irradiated in a nuclear accident they would have breached European intervention levels.

The lobsters are just one species affected by what Greenpeace calls the dramatic increase in contamination of south-west Scotland's marine life from nuclear waste dumped into the Irish Sea from the plant.

In a report released yesterday, it was claimed that the levels of radioactive isotope Technetium 99 in the lobsters have soared since the Thorp Reprocessing plant opened in 1994. Levels of the isotope found in seaweed samples taken at Port William increased 30 times between 1992 and 1996.

Mr Shaun Burnie, of the Greenpeace research vessel MV Sirius, said that Sellafield must be forced to stop its ''dangerous polluting practices''.

''In 1994, BNFL was given the green light to increase its nuclear waste discharges into the environment. The warnings of serious increases in contamination of marine life were disregarded then, and they are still being disregarded by those charged with protecting the Scottish environment.''

Mr Burnie said the contamination was not limited to the Sellafield area.

''It takes less than three months for ocean currents to carry radioactive waste to the south-west Scottish coast. They are then carried through the North Channel between Ireland and Scotland, north past the inner Hebrides and Western Isles before reaching the North Sea in as little as nine months.''

Sellafield discharges eight million litres of nuclear waste into the Irish Sea every day, Greenpeace claims, and the dramatic increases in the levels of Technetium have led to calls from groups representing fishermen for all discharges to be stopped.

The Scottish National Party has also joined the calls for the level of discharges to be substantially reduced. Claiming that Sellafield is Scotland's Nuclear Dustbin Ms Roseanna Cunningham, the party's environment spokesperson, said the most alarming thing about the discharges was that they were legal.

''Both the Scottish environment and our marine-based economy are consequently being affected by the practices of Sellafield. These unusually high authorisations were granted to allow for a backlog of reprocessing and it is now the responsibility of the Government to reduce licences to pre-1994 levels and ultimately remove them altogether.''

However, British Nuclear Fuels Ltd, which operates the plant said Greenpeace was attempting to alarm the public by dressing up widely available information and presenting it as a something new.

A spokesman for BNFL, while not denying the accuracy of the Greenpeace figures, said the levels of Technetium 99 in the lobsters did not pose any health risk whatsoever. He attacked the use of the EC intervention levels saying it was inappropriate and misleading.

''Intervention levels were designed to act as pre-set precautionary values to be applied quickly in the event of a nuclear emergency. Their applicability is now being reviewed, but it is important to remember that they were never intended as a borderline between what is safe and what is not.''

He also said that discharges of Technetium had not come from the THORP plant but were related to the past and present reprocessing of Magnox fuel. The discharges arose from processing waste which had been stored on site pending the start-up of the Enhanced Actinide Removal Plant in 1994. The new plant cannot remove technetium, and no commercial techniques exist to do so.