The findings call into question the theory which caused near panic among parents when it was publicised on the ITV programme The Cook Report in 1994.
Antimony is used as a fire retardant in mattresses, and the research scientist Barry Richardson claims that the combination of a fungus in mattresses and urine and perspiration from the baby can combine with antimony to form a lethal gas. After the programme, Boots and other retailers withdrew mattresses from sale and thousands of parents contacted a phoneline.
Crucial to Mr Richardson's theory was the idea that antimony is found in mattresses but rarely encountered anywhere else. But Mike Thompson, reader in analytic chemistry at Birkbeck College, London University, said antimony found in babies does not necessarily come from mattresses.
He added that he was "very surprised" at the levels of antimony he discovered. When dust samples were taken from 100 homes at random around Britain, antimony was found in housedust at between 10 and 20 parts per million, compared with rocks and soil where it is found in 0.5 parts per million.
Joyce Epstein, general secretary of the Foundation for the Study of Infant Deaths, which funded the research, said yesterday: "Richardson claims the only way babies can absorb antimony is through mattresses. We have found that antimony is everywhere around you, in ordinary household dust as well as lots of other places.
"The corollary of that is there is no evidence, first, that antimony causes cot deaths or, second, that there is a problem with mattresses ... even if antimony was a problem, you cannot finger mattresses as being the only source
Mr Richardson, now based in Guernsey, said: "It is interesting they are doing research on antimony which means they must think it is significant. Previously the problem was that no one would say it is relevant."
Later this week Penguin will also publish a book called The Cot Death Cover Up?, by the New Zealand forensic scientist Jim Sprott, which also claims that antimony and phosphorous are behind unexplained infant deaths.
Cot deaths have fallen from 912 in 1991 to the present rate of between 300 and 400 a year. The lowering of the cot death rate is thought to be due to the "Back to Sleep" campaign launched in December 1991.
The campaign advised parents not to let babies sleep on their stomachs, not to let them become too hot or cold, and to keep them away from cigarette smoke. A survey in 1995 revealed that a baby whose mother and father smokes is five times more likely to be a cot death victim than one in a non-smoking home.
t The number of cot deaths in the Irish Republic shot up by 23 per cent last year after decreasing by 70 per cent in a previous five-year period, according to new figures. The rise in fatalities has still to be fully analysed, but Tom Matthews, professor of paediatrics at University College Dublin said the deaths were being associated with one or both parents smoking and with social deprivation.Reuse content