* TSX falls 88.33 points, or 0.70 percent, to 12,488.72 * All of 10 main sectors decline * Gold shares lose 2.2 percent as bullion prices ease * RBC slips 1.3 percent to play market's biggest negative influence By John Tilak TORONTO, May 15 (Reuters) - Canada's main stock index retreated on Wednesday, hurt by declines across all major sectors, after sluggish data from Europe and the United States revived concerns about the global economic recovery. Investors were disappointed after U.S. producer prices recorded their largest drop in three years in April as gasoline and food costs tumbled, and reports showed an unexpected drop in U.S. factory output last month. Germany's economy crept back into growth at the start of the year but not by enough to stop the euro zone from contracting for a sixth straight quarter, and France slid into recession. The weak data was a drag on prices of commodities like oil, gold and copper. "People are worried about the recovery stumbling," said Michael Sprung, president of Sprung Investment Management. "The numbers are indicating a knee-jerk reaction through the market, which is affecting people's perceived demand for commodities and prospects for manufacturing," he added. The Toronto Stock Exchange's S&P/TSX composite index was down 88.33 points, or 0.70 percent, at 12,488.72. All of the 10 main sectors on the index were in the red. The materials sector, which includes mining stocks, slipped 1.5 percent, hurt by a decline in gold shares. The gold sector, down 37 percent since the start of the year, fell 2.2 percent as a strong U.S. dollar pulled down bullion prices. "With the economy faltering and the debt levels generally rising, it's surprising to see the pressure continue on gold," Sprung said. He said the only explanation was that people are looking for safety in the U.S. dollar and U.S. Treasuries. A fall in the price of oil sent energy shares down 0.9 percent. Financials, the index's most heavily weighted sector, gave back 0.8 percent. Royal Bank of Canada, the country's biggest bank, fell 1.3 percent and played the biggest role in leading the market lower.