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#ColdWarHistory #PortonDown #LondonUnderground 55 years ago today, Porton Down scientists conducted a second covert release of live bacteria on the London Underground system. Porton were investigating how far a Biological Warfare aerosol would spread in the London Underground. 
#ColdWarHistory #PortonDown #LondonUnderground At exactly 13.00 on 01 May 1964, a trainee LU Engineer covertly dropped a converted face-powder case from the rear window LU train while it traveled northwards between Colliers Wood and Tooting Broadway.
#ColdWarHistory #PortonDown #LondonUnderground The face-powder box was designed to break open on impact and contained two types of live organisms - Bacillus globigii (BG) spores & T.1 coliphage. BG is now considered to be a human pathogen by the US Institute of Medicine.
#ColdWarHistory #PortonDown #LondonUnderground The resulting enormous live bacterial spore cloud arrived at Tooting Broadway platform 10 minutes later. Those standing on the platform would have inhaled at least 2,400,000 BG spores over the first five minute period.
#ColdWarHistory #PortonDown #LondonUnderground It's important to recognise that the Bacillus globigii spores, obtained from Fort Detrick (the US germ warfare facility), were designed by Porton Down to evade the body's natural defences & penetrate the deepest part of the lungs.
#ColdWarHistory #PortonDown #LondonUnderground Porton Down staff covertly sampled the air at many points across the London Underground in order to measure the spread & concentration of the massive live bacterial cloud. Some points used a covert 'suitcase' sampler.
#ColdWarHistory #PortonDown #LondonUnderground Over a 30 minute period, Passengers and staff at Tooting Broadway would have inhaled at least 8,575,500 Bacillus globigii spores. Other spores would've settled on hair, clothes and food and therefore be carried out of the Tube.
#ColdWarHistory #PortonDown #LondonUnderground Examination of samples taken by Porton Down showed that even after travelling 23 stops, the original LU train car still contained 200 spores per 20 litre of air/per min. The contamination across the LU system was considerable.
