Medical experts say that ministers have triggered an unnecessary radiation scare that has led to thousands of people needlessly demanding checks for contamination.

More than 5,500 passengers jammed a British Airways hotline yesterday after the revelation that minuscule traces of polonium-210 were found on aircraft flying to Moscow. BA said that it had also 60,000 hits on its website dealing with the alert. Another 1,700 people have contacted NHS Direct.

Most of the callers fear that they were in the same Piccadilly restaurant, Mayfair hotel or West End offices as Alexander Litvinenko on November 1, the day he fell ill. Only 24 have been referred to a specialist clinic. So far nobody has shown any signs of exposure.

Medical staff who treated him at two hospitals, Barnet General and University College, have been checked; none has shown any signs of exposure.

The Times has also learnt that Litvinenko’s body will be returned to his wife in a sealed container that can never be opened because of the danger from the radiation that killed him. Health officials have issued strict guidelines for the burial, expected to take place next week in London.

Relatives were told yesterday after the opening of an inquest into his death that it would be too dangerous to cremate the body for the next 22 years because of the risk of radiation entering the atmosphere. The family will be given the body after a post-mortem examination due to be carried out today under strict safety guidelines. Experts insist that the chances of contamination being spread by the body are “remote”.

Nick Priest, a radiological expert at Middlesex University, said: “Why was there a need to alert 33,000 passengers who have used aircraft over five weeks when the chances of anyone being contaminated are infinitesimal?” A senior figure in the Health Protection Agency said: “Maybe we have gone overboard. When the word ‘radiation’ is mentioned, people get scared but the authorities want to be safe, not sorry.”

John Reid told MPs yesterday the HPA believed that “the risk of exposure to this substance remains low”. Polonium-210 had been found in a dozen locations, the Home Secretary said. They include two BA aircraft, although a third, a Boeing 767, had been grounded in Moscow until last night when it was announced that it would be flown back to London. The agency said yesterday that one aircraft had been cleared. Tessa Jowell, the Culture Secretary, and Lord Coe took a flight to Barcelona on one of the affected planes on November 16.

Both have been told that they were not sitting on an area of the plane that is potentially contaminated. A government source said last night that Ms Jowell was accepting health advice that there was little risk to passengers.

British Airways said that 3,000 staff were involved in the health alert relating to its grounded aircraft, adding that 221 flights to ten destinations from October 25 to November 29 were being examined.

Security sources have told The Times that some of the 12 locations where traces of radioactivity have been found were never visited by Litvinenko. It is thought that an office at 58 Grosvenor Street and the Sheraton Park Lane hotel were used by one of three Russians understood to be key suspects in the investigation. Counter-terrorist detectives are tracing their movements. Special Branch officers have studied CCTV footage to spot them among passengers at Heathrow. The suspects also frequented some of the 12 other places that experts have examined but say are free of any traces of polonium-210.

Passenger seats on BA flights that the men are known to have travelled on in the past five weeks have shown exposure to radioactivity. Experts say it is unlikely that they will be able to say if the polonium-210 found on one jet was left there by a passenger travelling to London or on a return journey.

Police refuse to divulge the identities of the three men, but they were identified as suspects within 48 hours of Litvinenko’s death. They will not say if they are the three Russians Litvinenko met at the Millenium Hotel on November 1.

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