At 9:51am EST (1451 GMT), the Toronto Stock Exchange's S&P/TSX composite index was down 87.35 points, or 0.57 percent, at 15,247.46.
The biggest riser was cannabis company Canopy Growth Co , which gained 10.6 percent and the biggest faller was Element Fleet Management Corp, a provider of services and financing for commercial vehicle fleets, which fell 29 percent after issuing a profit warning on Monday.
The index posted no new 52-week highs and 37 new lows.
The financials group slipped 0.6 percent. The materials group, which includes precious and base metals miners and fertilizer companies, lost 1.1 percent.
Of the index's 10 main groups seven were in negative territory.
In the financial sector, Toronto Dominion Bank fell by 0.9 percent and Royal Bank of Canada was down 0.8 percent.
Canada's trade deficit unexpectedly ballooned to C$3.19 billion ($2.55 billion) in December as imports grew faster than exports for the second month in a row, data from Statistics Canada indicated on Tuesday.