Hadi Khosorojerdi lies on his bed in a Tehran hospital, a drip in his arm. In a weak, breathless voice the former Revolutionary Guard recalls the day in August 1987 that he was hit by shrapnel on Majnoon island during the Iran-Iraq War. As he lay unconscious on the ground, the Iraqis unleashed mustard gas.

Mr Khosorojerdi was 19. Amazingly he survived, recovered and went on to marry and have two children. But in recent years he has developed severe respiratory problems and nine months ago was admitted to Sasan hospital. “I trust in God,” he replies when asked his prognosis, but the nurse shakes her head sadly. “He has lung cancer,” she says quietly. “He will die.”

Mr Khosorojerdi is not alone in his plight. Two dozen other victims of Saddam Hussein's chemical weapon attacks fill the hospital's specially designated wards — most are middle-aged men but there are women too. All are slowly dying.

Across Iran thousands more cases are emerging each year because the effects of mustard gas poisoning can take a decade or two to surface. Although the war ended 18 years ago, at least 55,000 Iranians are now being treated. Another 40,000, mostly civilians, need help but lack documents proving that they are war victims. A million Iranian soldiers and civilians may have been exposed to chemical agents during the 1980-88 conflict.

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“The number of new cases is unbelievable,” says Shahriar Khateri, of the Society for Chemical Weapons Victims Support. “We have new ones every day.”

Iraqi Kurds yesterday commemorated the 20th anniversary of Saddam's infamous chemical weapon attacks on his own citizens in the town of Halabja, in northern Iraq, but Dr Kahteri says that the Iranians are truly “the forgotten victims of Saddam's war crimes” because of their country's pariah status.

Few foreigners know of their fate, he says. They cannot receive the medical care available in the West. Sanctions and visa problems inhibit international collaboration on research. “Regardless of political tensions between governments, this is a humanitarian issue,” he insists. “There are many scientists and experts in countries like the US and UK who could help these victims, but unfortunately there's a political barrier...The situation is getting worse and worse and we can't do anything.”

Dr Khateri, 37, is a victim himself. He went to the front line at 15, one of thousands of teenagers who rushed to defend the new Islamic Republic from its neighbour. He survived an attack with nerve agents by injecting himself with atropine, but inhaled mustard gas in a second attack. In 2004 he developed respiratory problems that he accepts will become progressively worse because there is no cure.

Saddam launched more than 350 chemical weapon attacks across the border. Iraq has since admitted using 1,800 tonnes of mustard gas and 740 tonnes of the highly toxic nerve agents sarin and tabun. It was the worst use of mustard gas since the First World War and the first use of nerve agents. Iranian soldiers often had inadequate masks and little detection and decontamination equipment. Civilians had nothing.

About 7,000 Iranians died immediately, most from nerve agents. Mustard gas victims often develop symptoms years later. “The only thing we can do is slow development of the disease,” says Hamid Jamali, a Sasan hospital doctor who has watched many patients progress from coughing up blood and phlegm to the point where they can no longer breathe. Other symptoms include eye damage, cancers, weakened immune systems and congenital diseases. Dr Khateri says that victims of chemical attacks also suffer disproportionately from psychological problems.

Sasan's patients are mostly former soldiers or members of the Basij, Iran's religious volunteer militia. They all tell similar stories of rushing to the front as teenagers fired with patriotic zeal, of gas attacks that smelt like rotting vegetables, of feeling sick and dizzy with running eyes and noses. Several returned to battle after short spells in hospital and survived second or even third attacks. Years later they developed respiratory problems that left them unable to work or exercise. Some pulled up pyjama tops to reveal torsos covered in vivid red spots.

They have all seen colleagues die. They know that their days are numbered. But they express little self-pity. Indeed, many say that they relish death. “It will make me a martyr,” explains Mashollah Bababeighi, 43, a former Revolutionary Guard with a thick cough and wheezy voice. “It will be the greatest source of pride,” says Mostafa Hussein, 47, a former Basiji.

For Saddam, they feel only hatred. “Damn him,” Mr Khosorojerdi whispers as he lies dying.

Opposition shows signs of resurgence

Critics of President Ahmadinejad did well enough in parliamentary elections on Friday to suggest that he cannot count on re-election next year (Martin Fletcher writes). With 190 of the 290 seats decided, pro-Ahmadinejad hardliners had won about 70, while “pragmatic” conservatives critical of his economic record and foreign policy took about 43. Reformists won 31 — a strong performance given that many of their best candidates were disqualified — and independents 38. The European Union said that the elections were “neither free nor fair” while the Bush Administration said that they were “cooked”. The authorities claimed turnout to be about 60 per cent. Counting is expected to finish today.

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