Sentiment was also pressured by worries about the impact of a long-drawn U.S.-China trade war on global growth, with yields on U.S. and Germany bonds plummeting as investors sought safe-haven assets. Financials slipped 0.9% in early trade.
Only the materials sector was trading higher, up 2.3%, as gold's role as a safe-haven asset propelled the metal to a six-year peak.
The energy sector dropped 1.5% as U.S. crude prices were down 2.8% a barrel, while Brent crude lost 2.5%. [O/R]
Oil prices were weighed down by the deepening trade tensions that weighed on the outlook for energy demand. [O/R]
Energy companies were the biggest decliners on the TSX. Nuvista Energy dropped 8.5%, while Ensign Energy Services Inc slipped 5.6%.
At 9:43 a.m. ET (13:43 GMT), the Toronto Stock Exchange's S&P/TSX composite index was down 58.22 points, or 0.36%, at 16,091.27.
On the TSX, 58 issues were higher, while 176 issues declined for a 3.03-to-1 ratio to the downside, with 29.45 million shares traded.
The largest percentage gainers on the TSX were gold miners B2gold Corp, which jumped 13.4%, and Semafo Inc, which rose 9.3%.
The most heavily traded shares by volume were Enbridge Inc, Troilus Gold Corp and B2gold Corp.
The TSX posted 23 new 52-week highs and 20 new lows.
Across all Canadian issues there were 109 new 52-week highs and 49 new lows, with total volume of 50.78 million shares.
(Reporting by Amy Caren Daniel in Bengaluru; Editing by Sriraj Kalluvila)