Undercover trading-standards officers checking for excessive colourants in curries found the worst case in Yorkshire and Humberside in a Bradford takeaway.

They say the garish red chicken tikka masala bought in Britain's "curry capital" contained six times the permitted level of substances which can cause health problems.

The takeaway was one of 82 samples taken across the region.

A total of 22 were found to be above the limit - most of them three or four times the permitted level.

Sampling is still being done and the Bradford tests have not finished.

All the Yorkshire and Humberside premises which sold food with colourants exceeding the levels have received letters telling them of the findings.

But West Yorkshire Trading Standards Manager Graham Hebblethwaite said today there would be follow-up visits and businesses still breaking the limits could be taken to court for contravening food regulations and face fines of up to £5,000.

Bradford Council is expected to launch a campaign to stop chefs using the colourants. Permitted colours include tartrazine, sunset yellow and ponceau, which have been linked to hyperactivity in children and to allergic reactions including skin rashes and breathing difficulties.

The district will now be targeted by health officers in a bid to stop the practice.

During the campaign, the public will be urged to shun brightly coloured curries which sometimes obviously contain the colourants.

And one curry expert warned today that although they may look better, excessive colourants could spoil the taste.

Mohammed Aslam, managing director of the Aagrah group of restaurants, said: "It is not necessary to use artificial colours to this extent to get a perfectly acceptable chicken tikka masala.

"I believe Indian cooking should be authentic - tomato powder, red chillies and turmeric should give sufficient colour."

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