* TSX down 203.32 pts, or 1.7 pct, at 11,657.34 * Touches lowest level since Dec. 20, 2011 * Political instability in Europe hurts sentiment By Jon Cook TORONTO, May 8 (Reuters) - Toronto's main stock index fell more than 200 points on Tuesday with mining and energy shares selling off as political volatility in France and Greece threatened to escalate the euro zone debt crisis, denting demand for riskier commodities. Financial markets are worried the election results in Greece and France, where new governments have stated their opposition to austerity measures, could lead to a new phase of the crisis. Canadian stocks were on track for their fifth-straight drop as the heavyweight materials group tumbled more than 3 percent as miners were hit by a sharp drop in gold and base metals prices. Losses were led by top gold producers Barrick Gold and Goldcorp Inc. Barrick, the world's largest gold miner, fell 3.6 percent to C$36.32 and Goldcorp sank 3.9 percent to C$34.53. "With the decline in prices you're starting to get that cleansing process where the baby gets thrown out with the bath water," said Arthur Salzer, executive director and chief executive officer of Northland Wealth Management. Base metals miners fell nearly 4 percent, led by Teck Resources, down 4.4 percent to C$32.83, and First Quantum Minerals, off 2.2 percent to C$17.73. Top fertilizer producer Potash Corp slumped 2.2 percent to C$40.96, a reflection of the reduced outlook for global growth as potash is used to grow key crops such as soy beans and corn. At 11:07 a.m. EDT (1507 GMT), the Toronto Stock Exchange's S&P/TSX composite index was down 203.32 points, or 1.7 percent, at 11,657.34, putting it on track for its lowest close since Dec. 20, 2011. The TSX has fallen more than 5 percent since the beginning of May. Energy shares were down again on Tuesday, slipping 2.3 percent as Brent crude oil dipped below $112 a barrel, down more than 6 percent so far this month. Suncor Energy, Canada's largest oil producer, dropped 2.5 percent to C$29.48 to lead the influential sector's losses. Canadian Natural Resources was down 3.2 percent at C$30.63 and Encana Corp fell 2.7 percent to C$20.78.