* C$ hits 2012 low of C$1.0366 vs US$, or 96.47 U.S. cents * Soft U.S. data, euro zone fears weigh * Canadian 10-, 30-year bond yields at record lows By Claire Sibonney TORONTO, May 31 (Reuters) - The Canadian dollar slumped to its weakest level against the U.S. dollar since late December on Thursday, while long-term bond yields hit record lows, as investors shunned riskier trades on signs of soft U.S. growth and worries about Spain's debt troubles. The Canadian currency touched C$1.0366 against its U.S. counterpart, or 96.47 U.S. cents, its softest level since Dec. 20. The commodity-linked currency weakened after a report by private payrolls processor ADP showed U.S. private employers created 133,000 jobs in May, fewer than the expected 148,000. And new claims for unemployment benefits rose by 10,000 for the fourth straight weekly increase. The data comes ahead of Friday's key U.S. payrolls report. Markets were also disappointed by data that showed U.S. first-quarter growth was revised down and Midwest business activity slowed considerably. "Risk sentiment just continues to plunge by the day," said Mazen Issa, Canada macro strategist at TD Securities. "Things were holding in fairly steady until equities opened and you saw the Canadian dollar just drop." The S&P 500 and S&P/TSX composite index both fell and were headed for their worst month since September. At 12:01 p.m. (1601 GMT), the Canadian dollar was at C$1.0355 against its U.S. counterpart, or 96.57 U.S. cents, down from Wednesday's North American session close at C$1.0292 against the U.S. dollar, or 97.16 U.S. cents. Issa sees the Canadian dollar weakening beyond C$1.04 should Friday's Canadian GDP data and U.S. non-farm payroll report dismay markets. In the near term he said the currency should hover between C$1.03 and C$1.04 versus the greenback. "Europe remains unresolved and there's a big even risk centered around June 17 with the Greek election," said Issa. "U.S. data is not getting any better, so there's not a lot of positive things to latch onto at the moment." Headlines out of Europe on Thursday did not help broader confidence. On Wednesday the Canadian dollar had firmed to a 2012 high of C$1.2721 against the euro. European policymakers' warnings about Spain's banks and Greece's survival in the euro area pushed the euro to a two-year low against the U.S. dollar on Thursday and hastened a rush into safe-haven assets such as Austrian and French bonds, whose 10-year yields hit a euro-era low. Canadian government bond prices also picked up steam across the curve, sending longer-dated yields to record lows. Canada's benchmark 10-year bond yield hit a record trough of 1.711 percent, while the 30-year yield touched a record low of 2.276 percent.