By Alan Irving

Last updated 17:02, Wednesday, 16 April 2008

MILK on a local farm in the Sellafield area has been contaminated by higher levels of radioactivity which has entered the food chain.

Abnormal concentrations of iodine-129 have been detected and sampling is taking place at other farms in the area to see if there are any traces of the same contamination.

The Environment Agency has given an assurance that there has been no health risk from the radioactive iodine but how the increased amounts have got into the milk is still a mystery.

The contamination was picked up by Sellafield’s own monitoring team, which routinely samples milk around local farms.

Iodine 129 is said to be present already in local milk but in very low concentrations, sometimes undetectable. The higher levels have since gone down on the farm concerned.

“There is no obvious explanation for the increase,” the Environment Agency’s Andrew Mayall told the West Cumbria Sites Stakeholder Group, the independent health and safety watchdog for Sellafield.

“Concentrations of iodine-129 in samples of milk from a local farm have significantly increased in recent months but it is significant only in terms of it being an unusual trend, not in radiation doses to the public,” he told the meeting in Whitehaven.

After the meeting, chairman David Moore, himself a former Sellafield milkman, told The Whitehaven News: “There has been no health risk whatsoever, but there was a significant increase for a short period of time and it is still a matter for concern.

“We need to know where this has come from, how it has got into the food chain. It could even have come from a cow which might have eaten a particle lying in a field.

“Sellafield brought it to light themselves. Nobody is trying to hide anything and the last thing we want is people not buying local milk, but at the same time the local community needs some more reassurance.”

The Environment Agency says it is still carrying out investigations which include analysing samples from another nearby farm.

Samples are normally taken on Mondays in an area stretching from Drigg to Egremont but no further increased levels have yet been detected.

Iodine-129 is released as a result of fuel reprocessing at Sellafield, but mostly to sea.

Sellafield Ltd said: “Any presence of iodine-120 in milk could be down to either historic or existing discharges from the site.”

Asked what levels would be dangerous to humans, spokeswoman Ali McKibbin said: “At the levels we have monitored a person would have to drink 75,000 litres of milk to receive the dose limit for members of the public.”

David Moore added “I have been selling milk all my life and I had no idea that iodine-129 was already there. We rely on the Environment Agency and the Food Standards Agency to keep us abreast of situations like this.”

Many gallons of milk on local farms had to be poured away after the 1957 Windscale Fire but Sellafield say that only small amounts of iodine-129 was released then, the majority from the plutonium Windscale pile reactor was iodine-131.