Iraq is the rare country that imports gas but also burns natural gas from oil wells into the air. The wasted gas is enough to power 3 million homes. Burning it is making people sick.

The men of Nahran Omar, a village in the heart of southern Iraq’s oil country, filed into a Shiite shrine clutching envelopes with X-rays, medical reports and death certificates.

They had come to describe the misery they say is caused by the burning gas and chemicals spewing out of the oil wells in their village. Each one had a sick son or a dying wife, an ill brother or sister.

“Imagine that in the town you come from every family has someone who has cancer,” said Khalid Qassim Faleh, a local tribal leader. “This is the situation in Nahran Omar.”

The chemicals in the air — in Nahran Omar and other oil towns across southern Iraq — come from the smoky orange flames atop the oil wells, burning away the natural gas that bubbles up with the oil.

Many countries have reduced the practice, known as flaring, in part because it wastes a precious resource. The amount of gas Iraq flares would be enough to power three million homes, according to the International Energy Agency.

But flaring also produces chemicals that can pollute the air, land and water. It has been shown to worsen asthma and hypertension, contribute to the incidence of some cancers and speed climate change.Iraq, however, still flares more than half the natural gas produced by its oil fields, more than any other country except Russia.