Alert over 'GM tortillas'

Most supermarkets have outlawed GM food

Tests on supermarket own-brand tortilla chips in the UK suggest they may contain traces of genetically modified (GM) maize.

The environmental group Friends of the Earth sent a selection of 20 different foods from British supermarkets for analysis at a German food laboratory.

The group says that the results show two types of GM maize have been used to make the snacks sold by Sainsbury's, Tesco, Safeway and Asda.

All the shops voluntarily outlawed GM food after coming under pressure from customers.

European ban

Both the varieties of maize which are alleged to have been identified are manufactured by the biotechnology company Monsanto.

GM food must be labelled in the UK

They are licensed for use in the US but have not been approved by the UK Government.

All four supermarkets have pledged to investigate the claims and carry out their own tests.

None of them has removed the chips from sale, despite appeals for them to do so by Friends of the Earth.

One of the maize products, known as GA21, is banned in the UK pending more information from Monsanto to prove that it does not produce allergic reactions.

And the other - known as DBT418 - has raised concerns that it could have an impact on the effects of antibiotics.

'Independent testing'

A spokeswoman for Asda said: "Since 1988, we asked suppliers to stop using GM ingredients. We have carried out regular and independent testing to ensure own label products are genuinely GM free."

Sainsbury's said it had removed GM food from 4,000 different product lines and would investigate the claims further.

And Tesco said that if the claims were confirmed, it would discuss the issue with its suppliers.

Friends of the Earth's spokesman said: "Why is it down to a pressure group like ours to do these tests?

"The government must learn the lessons of BSE and ensure our food is protected from illegal ingredients."