The Ministry of Agriculture is allowing carcasses of cattle which test positive in TB tests to be cut up and sold to supermarkets.
It had been widely assumed among doctors that cattle found to have contracted the infectious disease would be killed and instantly incinerated.
But the Independent on Sunday has learned that Government hygiene inspectors are merely removing TB lesions - visible tuberculous growths - before allowing the rest of the animal to be sold to butchers, shops and restaurants.
Around 30 cases of bovine TB are identified among humans every year and the infection can lie dormant for decades. But it is thought that some of the 6,000 TB cases in Britain are in fact bovine TB.
The disease, which is particularly dangerous to old people, can be contracted by eating beef which has not been properly cooked or milk which has not been pasteurised.
"Cows can pass TB to humans beings. Historically the principal route has been through milk," said Dr John Grange, an associate editor of the International Journal of Tuberculosis. "I wasn't aware that tuberculin- reacting cows were put in the food chain. If the meat was cooked properly it would be OK, but if it isn't it could be a problem."
The Ministry of Agriculture's current TB testing scheme is designed to "control infection in cattle so that it cannot get into the food chain or affect those working with animals". Government hygiene inspectors are trained to spot physical signs of TB so they can order them to be cut out of carcasses.
But doctors say the only guarantee that humans will not contract the disease is to make sure that cattle which have contracted TB are not used as meat.
"I am very surprised to hear that the carcasses of animals which have tested positive are not immediately destroyed," said one disease specialist.
Consumer groups have also questioned whether the safeguards are sufficient. They want the Government to review its safety guidelines and to be more frank with the public about the risks.
"We have always said that clear, independent information is vital for consumers particularly in an area like food safety," said a spokeswoman for the National Consumer Council. "It is exceedingly worrying that people may be eating beef from TB-infected cattle as it's a disease which is a human disease as well. MAFF should urgently reassess these guidelines and examine whether this is a fool-proof safeguard."
MAFF has admitted that there is a chance that hygiene inspectors may not spot every TB lesion on the cattle. But they said that the risk of contracting TB from infected meat was "negligible" if properly cooked.
"The meat hygiene inspectors check all carcasses for consumption and that includes checking for TB," said a MAFF spokesman. "They are trained to do detailed inspections for TB. If it is obvious that the carcass is riddled with it, it will be disposed of. If the inspector is satisfied that it is a local lesion, [the infected part] is removed and stained and disposed of. Any organism that is left in the meat would be killed in the cooking anyway so the risk to human health is negligible."
Bovine tuberculosis was rife among humans at the beginning of the century. In the 1930s 40 per cent of all dairy cows were infected with bovine TB. The illness was virtually eradicated after the Second World War by government testing and slaughter. But since 1996 the incidence of TB in British cattle has almost doubled.Reuse content