* TSX down 107.72 pts, or 0.91 pct, at 11,784.72
* Energy and materials issues plunge
* Oil, gold and copper prices fall (Adds details, analyst comments)
By Jon Cook
TORONTO, Nov 21 (Reuters) - Canadian stocks hit their lowest level in nearly six weeks on Monday as commodity prices sagged on worries about the global economic outlook and debt crises dominating headlines in Europe and the United States.
Shares of energy and mining companies were hardest hit as investors worried over the prospects for growth given the debt problems on both sides of the Atlantic.
A U.S. congressional committee said it failed to reach a deal to cut at least $1.2 trillion from the U.S. deficit over the next decade. Expectation of the failure helped lead to the broad selloff in riskier assets and currencies. [ID:nWEN1065]
The pressure on debt issued by the euro zone's troubled economies remains unabated, with yields on Spanish, Italian and Belgian bonds all rising. In a sign of the crisis spreading to countries once seen as safe, French yields also rose after Moody's warned about the country's credit rating.
"If the market is a little bit more fearful of a greater slowdown in the global economy commodities are going to get smacked," said Philip Petursson, managing director of the portfolio advisory group at Manulife Asset Management.
Commodity prices slid with the European outlook, as gold, oil, metals and grains tumbled. The Reuters-Jefferies CRB index .CRB, a global commodities benchmark, fell for the third straight session, hitting its lowest level in more than month. [ID:nN1E7AK1RF]
The Toronto Stock Exchange's S&P/TSX composite index .GSPTSE finished down 107.72 points, or 0.91 percent, at 11,784.72. The index at one point touched 11,636.12, its weakest level since Oct. 11.
The energy sector led the broader index lower, plunging 1.7 percent as oil prices fell and trading volumes remained tepid. [O/R]
Suncor Energy SU.TO was the biggest drag on energy issues and the broader market, tumbling 1.8 percent to C$30.94.
Mining stocks sagged as gold and copper prices fell sharply, pulling down the heavily weighted materials sector, which dropped 1.3 percent.
Base metal issues fell 1.7 percent as copper prices slid to their lowest levels in nearly a month on fears of a European slowdown and warnings from China about gloomy global growth prospects. [MET/L]
"The increased likelihood that you have a double-dip in Europe means that anything economically sensitive is selling off," said Bob Gorman, chief portfolio strategist at TD Waterhouse.
Tech Resources TCKb.TO was among the biggest laggards, tumbling 1.3 percent to C$34.69.
Gold extended last week's slide, falling more than 1 percent, swept lower by a U.S. dollar that gained on a flight to safety. [GOL/]
Goldcorp Inc G.TO was down 0.8 percent at C$51.46, with the overall gold subsector dropping 1 percent.
($1=$1.04 Canadian) (Editing by Jeffrey Hodgson)