RADIOACTIVE wreckage and tens of millions of landmines still blight Iraq after decades of war and the deadly violence that engulfed the nation after the 2003 invasion, the environment minister says.

Narmin Othman Hasan said a lack of funding and Iraq's fragile security situation was hampering efforts to clean up contaminated sites across the country.

She said that only a fraction of tanks and other wartime vehicles contaminated with depleted uranium have been successfully treated and disposed of by the Iraqi authorities.

"We have only found 80 per cent (of the contaminated sites)... because of the (lack of) security there are still some areas we can't reach," she estimated.

The twin menaces are the legacy of decades of conflict: the 1980-1988 war with neighbouring Iran, the 1991 Gulf war that followed Iraq's invasion of Kuwait and the 2003 US-led invasion of Iraq and its bloody aftermath.

The environment ministry's limited budget - around $US100 million ($120 million) compared to the "billions" that are judged necessary to tackle the country's myriad environmental challenges - also got in the way, Ms Hasan said.

Depleted uranium, a radioactive metal present in armour piercing bullets used by US-led forces during the 1991 Gulf War and the 2003 invasion, and which is twice as dense as lead, has been blamed for health problems from cancer to birth defects, but much research remains inconclusive.

"All radiation is dangerous - but how much depleted uranium radiation is affecting health, that is still under study," Ms Hasan said, adding that media reports of negative health effects from depleted uranium had contributed to a "panic" among the Iraqi public.

"It's two steps: treating and dumping. We can't just bring a tank and dump it, we must treat it and minimise it. It takes time."

But dealing with the landmines that continue to maim and kill innocent Iraqis was her most pressing concern, she said.

"For one person we have one mine planted. We have 25 million mines in Iraq - one quarter of the world's mines."

The deactivation and removal of mines, however, remains a controversial issue across the conflict-torn nation.

The United Nations has said the Iraqi army's decision to ban civilian-led mine-clearance operations is seriously damaging Baghdad's pledge to rid itself of the deadly munitions.

Iraq signed up to the Ottawa Anti-Personnel Mine Ban Convention last year, requiring it to clear all areas littered with such ordnance by 2018, but the United Nations warned in July that the target was in jeopardy.

Iraq's army banned civilian contractors from mine-clearing activities last December, citing security concerns. It has been claimed that some villagers have dug up unspent munitions and sold them to insurgents.