Official attempts by the Ministry of Defence to discredit a document about the dangers of depleted uranium have been undermined.

The document, dated March 1997, says that personnel exposed to the dust from the explosion of shells tipped with depleted uranium - or DU - increase their chances of developing lung, lymph and brain cancers.

The warnings are accompanied by specific measures for protection of those likely to be exposed. This appears to contradict directly the assurances by the Armed Forces Minister, John Spellar, earlier this week: he maintained that there was still no proven health risk from DU.

Spread the word

Not surprisingly, a senior MoD scientist was despatched to radio and television studios this morning to dismiss the document as the work of a junior officer, who probably regretted that his flawed research had been so widely publicised.

But it has now emerged that the document came with a covering letter, apparently signed the following month on behalf of a senior officer, requiring the information to be disseminated to all appropriate quarters.

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This letter explains that a new kind of ammunition is about to be introduced.

The covering letter summarises the precautions to be taken by anyone working in or around contaminated vehicles.

Hazard warning

That was the advice, then, to the Royal Armoured Corps, the Royal Logistics Corps and the Royal Electrical and Mechanical Engineers.

The letter is signed by AH Lyall Grant, RO2 for the COS - Chief of the General Staff, HQ, Quartermaster-General. If the information was to be disseminated so widely, at a senior level, how can it now be dismissed as a piece of flawed research with no basis in fact?

Yet that was the argument presented this morning by Professor Sir Keith O'Nions, the chief scientific adviser to the Ministry of Defence.

The Shadow Defence Secretary, Ian Duncan-Smith, is unimpressed. He says that the covering letter raises important questions.

So who would have written such a letter? Michael Codner is Assistant Director for Military Sciences at the Royal United Services Institute.

According to Downing Street, the Defence Secretary, Geoff Hoon, told this morning's Cabinet that he still believed depleted uranium posed no significant risk to British troops.