A SERIES of secret germ warfare tests on the people of Norwich were more widespread than initially thought, it emerged today. Four years ago, the Evening News revealed how a chemical cloud was released over the city in 1963 during an experiment at the height of Cold War paranoia. Now we have seen previously secret documents, which reveal boffins returned to drop more of the same chemicals over the city a year later. And researchers investigating the drops today expressed fears there was never conclusive proof the substances dropped on the city were completely safe.The experiments were carried out at Porton Down, a Ministry of Defence base near Salisbury, which conducted chemical and biological warfare tests. They today said two independent reports cleared the drops of any significant safety risk.

Planes were sent soaring into the skies above Norwich to disperse Zinc Cadmium Sulphide in March 1963 and then again a year later. An independent inquiry chaired by Cambridge University professor Peter Lachmann concluded four years ago there was nothing for families to fear from the original 1963 test.The report said the dose of cadmium — which has links to lung cancer and kidney disease — potentially received by inhalation was so small it was not a risk to health.The report, which looked at Norwich along with a string of other trials in the south of England, said the worst case would be the equivalent of the amount of cadmium inhaled in a normal urban environment in a period of between 12 and 100 days, or from smoking 100 cigarettes. The report said: "Although we fully understand the public unease that ensued when it was discovered, many years after the event, that large areas of Britain had been subjected to this form of experimentation, the existing evidence shows that no public health danger arose."But Michael Kenner, who has been investigating Porton Down for the past seven years, insisted there was no proof the chemicals were harmless."The people who were in close contact with the stuff were wearing surgical caps, gloves and home office respirators," he said."Used clothing was washed in a separate machine. No full study has ever been carried out."The building which the MoD kept the chemicals in was burnt to the ground by officials once tests concluded because boffins accepted it could be dangerous in it more purest form.According to once classified documents, police in Norwich were due to play a key role in the sampling of the chemicals, with special drums to test how far the particles penetrated.The list of sampling stations included police section boxes in Ketts Hill, Mile Cross, Earlham and Tuckswood, along with sites at the old Norfolk and Norwich Hospital, Boulton & Paul''s in Riverside, Cathedral Close, Nelson Street, Magdalen Road, Earlham Green Lane, Jessopp Road, Unthank Road, Lakenham Road, Newmarket Road and Heartsease Lane.In 2001 Norwich North MP Ian Gibson demanded answers about the tests and attended a meeting at Porton Down.Today Dr Gibson, chairman of the House of Commons science and technology select committee, said it was no surprise that more tests might have been carried out over Norwich.He said: "I have been to Porton Down and it is one of the most secret places in England, so I am not surprised at all."Porton Down ought to be opened up because the secrecy surrounding their work is quite spurious."The more the public know the more confident they will be in what is being done to protect them."Back in 2001 Dr Gibson said families could sleep easy after he assured the particles used in the 1963 test were harmless, but today he said he still had his concerns.He said: "I am not happy because these are heavy metals which can cause a risk to health. We have not been able to look at the data and assess it."Sue Ellison, spokeswoman for Porton Down, confirmed tests took place in both 1963 and 1964, but said the public had nothing to fear."There were two independent inquiries about health and safety and the reports concluded there were no risks to health," she said."It''s important to stress that the information attained in the tests has been vital to this day."Some micro-organisms might not have survived well in the atmosphere and what the trials were trying to show was how far organisms could travel."The tests were carried out using harmless organisms to see that protection we needed."March 24, 2004www.eveningnews24.co.uk