SALAD labelled as "ready-to-eat" is more dangerous than beefburgers, a top food expert has said, following a spate of Cryptosporidium infections linked to the product.
Certain types of bacteria found in the pre-cut salad bags can be almost impossible to kill, Professor Hugh Pennington said, unless the leaves are irradiated – a process the public would oppose.
His claim follows a Health Protection Agency investigation into an outbreak of salad-linked Cryptosporidium infections that affected around 300 people in England and Scotland in May.
In the analysis of the exposure to different salad vegetables a significant statistical association was found between infection and the consumption of pre-cut spinach.
When specific retailers were included in the analysis, the strongest association with infection was found to be with consumption of ready to eat pre-cut mixed salad leaves from a major supermarket chain.
"Together these findings suggest that one or more types of salad vegetables could have been contaminated," said the HPA.
Professor Pennington said the case also followed on from several in the USA where they are "very worried" about "washed and ready-to-eat" bagged salad.
Last year produce giant Dole issued a recall on its American Blend bagged salad in 10 states in those two regions, after the Tennessee Department of Health found listeria bacteria in one sample.
Professor Pennington said: "It is generally safer to eat a burger than the salad that goes with it.
"Despite the recent horsemeat and other scandals, the meat can be traced and through a rigorous process that checks for its quality etc.