Canada's main stock index fell on Tuesday, weighed by energy and material stocks, as data showed that foreign investment in Canadian securities was the lowest in six months in January.

Foreign investors bought a net C$1.27 billion ($1.02 billion) in Canadian securities in January, led by provincial government bonds, Statistics Canada said.

At 9:43 a.m. ET (13:43 GMT), the Toronto Stock Exchange's S&P/TSX composite index was down 39.68 points, or 0.21%, at 18,915.07.

The energy sector dropped 1.5% as US crude prices were down 1.7% a barrel and Brent crude lost 1.5%.

The materials sector, which includes precious and base metals miners and fertilizer companies, lost 0.8%.

On the TSX, 74 issues were higher, while 141 issues declined for a 1.91-to-1 ratio to the downside, with 23.97 million shares traded.

Oil producer Tourmaline Oil Corp fell 3%, the most on the TSX, and the second biggest decliner was Lundin Mining Corporation, down 2.6%.

The largest percentage gainer on the TSX was GFL Environmental Inc, which jumped 3.4%, after the environmental services company announced it would acquire Terrapure Environmental Ltd.

Its gains were followed by semiconductor maker Celestica Inc, which rose 2.5%.

The most heavily traded shares by volume were Hydro One Ltd, Canadian Natural Resources Limited and Whitecap Resources Inc.

The TSX posted 16 new 52-week highs and no new low.

Across all Canadian issues there were 108 new 52-week highs and eight new lows, with total volume of 52.90 million shares.