A survey has found that a staggering 57 percent of Surrey's Indian and Bangladeshi restaurants are putting potentially dangerous levels of artificial colours into their curries, especially chicken tikka masala, the Britons' hot favourite.

The offending colours, which are only dangerous if consumed excessively over a period of time, are the chemicals Tartrazine (E102), Sunset Yellow FCF (E110) and Ponceau 4R (124).

Surrey County Council's Trading Standards Service, after collecting samples from randomly selected 102 restaurants across the country, said that 58 were found to be breaking the law while 44 passed.

"Some areas came out better than others 11 restaurants in North Surrey passed with flying colours, while Guildford, Surrey Heath, and Reigate & Banstead could only muster one in each area," says the study.

The food colourings have been linked to hyperactivity in children, allergies, asthma, migraines - and even cancer. All three chemicals are banned in various other countries around the world, including the United States, Norway, Finland and Australia.

But the survey - carried out as part of a brand-new Trading Standards initiative, the Surrey Curry Club - found majority of Surrey restaurants continuing to serve vivid bright red meals to customers in spite of previous education campaigns.

In the last half-century, Bangladeshi curry has become more traditionally English than English breakfast. As of former foreign secretary Robin Cook, the nation's "number-one favourite meal", chicken tikka masala, is now national dish of Great Britain.

At present the number of Bangladeshi restaurants reached 9,500 from 3,000 in 1980 with business of three billion pound sterling a year. These restaurants employ over 80,000 people serving 71 million meals a year. People believe that without the British Bangladeshis the wave of the smart Indian restaurants wouldn't be here.

Now Surrey Trading Standards plans to test the remaining restaurants in the county as part of an ongoing public education programme. In an effort to spread the word about safe colouring level, Surrey Trading Standards & Spice Business magazine launched consumer-awareness campaign at Epsom Down's Surrey famous Le Raj Bangladeshi restaurant this month. This will prove to customers that their curries are safe to eat and help spread the message about harmful curry colourings.

But the problem does not just lie with the chefs. According to restaurant owners and Trading Standards, the message needs to get across to the public that red is not always best, and that Indian dishes can be just as tasty if cooks stick to legal levels of artificial colours.

Enam Ali, editor of Spice Business magazine, said: "We know customers sometimes pick where they want to eat because they like the vivid colour of the curries. They do not realise that they can eat the same product which tastes just as good but it just looks a bit paler because it uses natural ingredients like beetroot to achieve the colour".