The safety of every food colouring and additive is being assessed independently by the European Food Safety Authority. Food safety experts expect most of these artificial colourings to be banned or phased out within two years.

The Food Standards Agency made clear yesterday that it had the option to introduce a unilateral ban, but it believes that an EU-wide ban would be more effective, especially as many manufacturers operate across the Continent. Scientists at the food safety authority’s headquarters in Palma, Italy, have examined the Southampton research findings and are preparing a report for the European Commission.

Some experts believe that action may be taken sooner on colourings than on the preservative sodium benzoate while manufacturers resolve technical difficulties. Sodium benzoate extends the shelf-life of drinks to about two years. Without it, many products would have to be refrigerated while in storage.

The links between artificial colours and hyperactivity in children have been known since the 1970s and companies have been lobbied by parents and health campaign groups to remove them. Nestlé has removed artificial dyes from Smarties, and Burton’s Foods removed them from its Jammie Dodgers after consumer concerns.

Leading brands, including super-market own-labels, are unlikely to contain many of these additives. Sainsbury’s Kids range is already free from artificial flavourings, colours and sodium benzoate, and the company is reformulating more than 12,000 of its own-label items. A spokeswoman said that it was seeking natural alternatives in canned strawberries, raspberries, glacé cherries, processed peas and angel cake. She said that any additives were clearly labelled.

Marks & Spencer has also removed all artificial colourants and flavourings from 99 per cent of products and has even introduced a new range of gourmet jelly beans, using natural colours such as beetroot red, concentrated plum, pear and pineapple juices or banana, peach and raspberry fruit purées.

Consumers should be suspicious of any brightly coloured food and drink products, especially in cheaper products. Icing on cakes and biscuits, sweet desserts, instant pudding mixes, some jellies and confectionery are the most likely candidates for E numbers. Sweets that are sold loose and are frequently found in children’s birthday party bags are also prime suspects.

Malcolm Kane, a food technology consultant, campaigns for the removal of additives. He said that after the war there were hundreds of artificial colourings but these had been whittled down over the years by health concerns. “What we are left with is about 12 azo dyes still found and deemed safe to use in foods. But now is the time to ban them from foods in the precautionary principle. We need to do this for food security.

“Everyone will remember the illegal use of Sudan I red dye in scores of products. There are other illegal azo dyes but the testing procedure makes it difficult to distinguish between a lawful and illegal dye.

“It would make the control of such illicit dyes much better. We could test for azo dyes and if any were found, food would immediately be removed from human consumption.”

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