TORONTO (Bloomberg) — Canadian raw-materials and industrial companies such as Alcan Inc. and Bombardier Inc. declined on concern that slowing economic expansion may curb profit growth.Energy producers including Petro-Canada climbed as colder weather in the Northeastern US lifted natural-gas prices to a one-month high. The Standard & Poor’s/TSX Composite Index was little changed, slipping 13.22, or 0.1 percent, to 12,705.77 in Toronto.

“Some people are getting negative on the Canadian economy,” said David Cockfield, who helps manage $1.1 billion at Leon Frazer & Associates Inc. in Toronto. “I think that’s too early. There’s still enough money looking for a home to keep the market advancing.”

The Bank of Canada last week cut its forecast for economic growth in the world’s eight-largest economy. Canada’s gross domestic product will expand 2.3 percent this year, less than the 2.5 percent that was forecast in October, because of a drop in US demand for Canadian automobile and building material exports, the central bank said. It kept its forecast for a 2008 expansion of 2.8 percent and said the economy will stay near full capacity through that year.

Exports account for more than a third of Canada’s GDP; commodities such as metals and energy make up more than half of the exports.

A measure of raw-materials shares lost 0.5 percent.

Alcan fell 89 cents to C$56.21. The world’s second-largest aluminium producer revised its cost estimate for the Gove alumina project in Australia to $2.3 billion and delayed the start of the refinery expansion by a quarter.

Potash Corp. of Saskatchewan Inc., the biggest maker of the fertiliser after which it is named, lost C$4.75 to C$169.21.

Industrial shares declined 1.7 percent as a group, and was the biggest drag on the S&P/TSX alongside materials shares.

Bombardier, the world’s third-biggest maker of civil aircraft, fell 8 cents to C$3.98, after Wachovia Securities downgraded its larger rival Boeing Co. on concern deliveries for new aircraft may be delayed.

CAE Inc., the world’s biggest maker of equipment for training pilots, dropped 20 cents to C$11.49.

Canadian National Railway Co. slipped 53 cents to C$51.84. The nation’s largest railroad is scheduled to report fourth-quarter results tomorrow.