The day germ warfare came to Tooting Broadway

In 1963, bacteria were released as a trial in the Tube. Did it help us to deal with the threat of biological attack? Er ... no, says Brian Balmer

Could London suffer the same type of chemical weapons attack that hit the Tokyo subway last week? The question has been worrying people since the 1930s. Then, with the growing threat of war with Germany, the main anxiety was that the capital was easy prey for sabotage. But these fears really peaked in the late 1950s, when a secret government committee discussed the feasibility of carrying out biological warfare simulations in the London Underground. It took five years of agonising about the political sensitivities involved before a bacterial dispersion test on the Northern Line - revealed in documents released in the Public Records Office under the Thirty Year Rule - was carried out, in 1963.

At lunchtime on 26 July 1963, the trial supervisor dropped a small face- powder tin, containing 30g of the bacterium Bacillus globigii, from the window of a train travelling between Colliers Wood and Tooting Broadway. The report of the trial stated that this bacterium was "not pathogenic and does not cause food spoilage or have other undesirable properties."

The test itself was so straightforward that no scientists were involved in carrying it out. Only London Transport workers were needed. Their job was to collect samples over the next 12 days from the air and from dust throughout the Underground. These samples were examined by researchers at the Ministry of Defence research establishment at Porton Down in Wiltshire.

How far had the bugs got? Some turned up as much as 10 miles north in Camden Town. The report concluded that "bacterial spores can be carried for several miles in the Tube system", and that "trains travelling through an aerosol become heavily contaminated internally".

Although the details in the public domain are scant, there is evidence that the Northern Line trials were not the first to be conducted in Britain. The 1963 trial is described as "the logical sequel to earlier trials carried out on British Railways and in the London Post Office cable tunnel system". Public transport was not, however, the only target envisaged as being vulnerable to attack. Committee minutes from 1961 mention that "trials in the underground `citadel' of government buildings had shown wide travel of spores".

Despite its simplicity, the Tube trial was preceded by a long period of debate and negotiation involving scientists, politicians and the London Transport Executive. Two years previously, members of the Biological Research Advisory Board had advised against such trials on the grounds of "political opposition to their conduct". One scientist on the board felt a sabotage attack was a "trivial hazard and adequately predictable from existing knowledge", especially in comparison with the threat of attack by bombing or spraying an entire city. Yet the board concluded that if trials were banned, they could not advise on either the potential or counter measures that might be taken.

Opposition to the tests was more on the grounds of public relations than safety. Even when approval was given in 1963, London Transport was "concerned about a suitable cover story to allay possible public suspicion". At Cabinet level, the Secretary of State for War (at that time, John Profumo) expressed concerns over the use of living organisms in the trials. But according to the minutes of the Biological Research Advisory Board, "the Minister was concerned solely about public reaction to tests".

What happened after this trial? The relevant documents are still classified (and may remain so), but we do know that by October 1963, scientists were planning further tests on the Underground system. They proposed using less hardy organisms which more closely resembled pathogens. Yet it is not clear what value the tests had. Unfortunately, in the face of the fears evoked by the Tokyo attack, they gave rise to almost no suggestion for countermeasures. Only one member of the Biological Research Advisory Board was able to make a suggestion: the closure of floodgates in the Underground system.

So the old anxieties remain, much as they were first envisaged in the 1930s. During this time the Committee of Imperial Defence's Sub-Committee on Bacteriological Warfare was established. This was in response to reports that German spies had been testing biological warfare agents on the Paris Mtro. In 1937, the committee agreed that Great Britain would be particularly susceptible to a civilian attack from biological agents. Scientists on this committee also believed that sabotage attacks were far more likely than any attempts to spread epidemics by dropping material from planes. This opinion was also supported by the director of Naval Intelligence who, in 1938, reported that Russia would be prepared to use bacteria to poison water supplies in the event of war.

Last week's events in Tokyo show that we are right to be concerned now about terrorist use of what have been termed "the poor man's atomic bombs". There is, none the less, an important difference between the Tokyo incident and what the ventilation trial was attempting to simulate. The 1963 test was examining risk from bacterial agents, a category of weapon prohibited under the Biological Weapons Convention since 1972. Although the convention is by no means a complete solution to problems of germ warfare, it does provide safeguards and a framework for further efforts at controlling these weapons. Sarin, the nerve gas used in Tokyo, is an organophosphate compound classed as a chemical weapon. The Chemical Weapons Convention was opened for signature in January 1993. It requires its signatories to establish national authorities to prohibit such weapons and closely monitor their precursors. Twenty-seven nations, including France and Germany, have so far ratified this treaty. Britain is not among them.

Brian Balmer is a lecturer in science policy, Department of History, Philosophy and Communication of Science, University College London.