According to a study by the Health Protection Agency, LACORS (the Local Authorities Co-ordinators of Regulatory Services) and local councils, 4.7% of salads and sauces were found to have worrying levels of bacteria, raising concerns about low hygiene standards.
A further 0.4% of salads and sauces tested from 1,277 kebab shops across England, Wales and Northern Ireland contained 'unacceptable or potentially hazardous' levels, meaning the food was unfit for human consumption.
Salad samples were tested for the bacteria E. coli, Staphylococcus aureus and salmonella, while sauces were also examined for Bacillus.
The research found that cucumber was the most likely salad vegetable to be contaminated, while chilli was the most likely sauce to be of low microbiological quality.
Dr Jim McLauchlin, director of the Health Protection Agency's Food, Water & Environmental Microbiology Services, said that while the 'vast majority' of takeaways were maintaining good hygiene standards, '5% were of an unsatisfactory or unacceptable microbiological quality, which is concerning'.
He added: 'The results emphasise that good hygiene practices and high standards of cleanliness must be maintained across the board at all times to prevent food from becoming contaminated.'
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