A SUPERMARKET giant is to escape prosecution over a labelling error which left a mother-of-two needing emergency medical treatment.

Trading standards have decided not to take Asda to court over a lasagne containing mushrooms which it sold to a Great Harwood woman severely allergic to the fungi.

Catherine Shackleton, 29, needed an injection from an emergency doctor after her throat swelled up after she ate part of the Asda-brand frozen meal bought from the Accrington store. There was no mention of mushrooms on the packaging and an investigation traced the mistake back to suppliers who put a new recipe meal in the old boxes.

Lancashire County Council trading standards chief Jim Potts said a thorough investigation had been carried out by officers which confirmed an error had been made. However, a criminal prosecution had to be ruled out because the council would probably lose and it would waste public money.

He said: "Asda are not denying the mistake but it appears their system of checks and procedures they have in place is good. They have taken all reasonable steps to ensure that the product was labelled properly.

"The addition of the extra ingredient into the product was done by the supplier contrary to Asda's control so there will be no realistic chance of a conviction. We have to follow Home Office guidelines on when to prosecute."

However, Asda were still liable to a possible civil action, he said.

Asda immediately withdrew the product when Catherine and her husband Neil, of Moss Street, complained and said they are willing to discuss compensation with the couple once trading standards formally complete their investigations.

Mr Potts said his officers would be in contact immediately so compensation could be discussed.

Mr and Mrs Shackleton and Asda could not be contacted for comment.