Despite the difficulty of access, inspectors had uncovered tons of deadly chemicals, among them mustard gas.

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He died before I was born of lung disease due to the mustard gas.

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It was Germany's devastating use of mustard gas in the trenches of the First World War which prompted Britain's research.

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An investigating judge ruled he was poisoned with thallium and mustard gas.

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This, he believes, will make it possible to work out which country, even which factory, supplied the original chemicals for the mustard gas - it will not be possible to trace the source of the nerve agents.

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But Iraq never accounted for all the 100, 000 chemical weapons it produced for use in the Iran-Iraq war, and there are fears that thousands of them, filled with either deadly VX or mustard gas, could be squirreled away.

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The Iraqi declaration is said to lack any explanation for what has happened to certain equipment and arms, such as shells filled with mustard gas, that had remained unaccounted for even when weapons inspectors were last in Iraq in the late 1990s.

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His father, a strict disciplinarian, first placed his hopes in the oldest son, Reginald, but he had gone off to fight in World War I and came home incapacitated, one lung destroyed by mustard gas, leaving the family's future to Albert, who was twelve years younger but precociously eager.

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Ziopharm devised a new version of an old mustard-gas based drug.

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