Teck Cominco has shut down its lead smelter in Trail, B.C., because of a chemical spill Wednesday night.

An unknown quantity of lead and fluoride escaped into the Columbia River approximately 11 kilometres north of the U.S. border before the spill was spotted, said provincial Environment Minister Barry Penner.

"My understanding is a spill occurred…from the lead production facility at Trail, part of the Cominco smelter there. They have shut down their lead production line. Ministry of Environment staff are in the process of conducting water sampling and analyzing the results," he said.

The refinery has been shut down and an investigation into the cause of the spill is underway, the Ministry of Environment said in a news release.

There have been no reports of harm to fish or wildlife, Penner said.

The spring runoff in the Columbia River is helping to dissipate the chemicals, he said, and it is unlikely any groundwater wells will be affected.