* S&P 500 falls 1.5 pct
* 10-yr Treasury yields hit 1.53 pct, lowest since Aug. '12
* U.S., European banking shares tumble
* Oil prices fall, gold hits highest in a year
* Dollar hits lowest vs. yen since Oct. '14 (Updates to open of U.S. markets, changes byline, dateline; previous LONDON)
By Sam Forgione
NEW YORK, Feb 11 (Reuters) - Stock indexes worldwide stumbled on Thursday on fears over the health of the global economy, with banking shares slumping on both sides of the Atlantic while safe-haven 10-year Treasury yields hit their lowest since 2012.
Investors nursed fears of slowing global growth and doubts over central banks' ability to support the global economy, driving the U.S. benchmark S&P 500 .SPX stock index 1.5 percent lower and the FTSEurofirst 300 .FTEU3 index of top European shares to its lowest level in two and a half years.
The dollar hit its lowest against the safe-haven yen since October 2014 of 110.985 yen, and was on track for its worst week against the Japanese currency since 2008 on the fears over the health of the global economy.
"The key driver is this immense pessimism in asset markets, unwillingness to hold anything but the safest assets," said Steven Englander, managing director and global head of G10 FX strategy at Citigroup (N:C).
Banks in Europe fell more than 6 percent .SX7P , making them the worst-performing sector and widening their losses for the year to about 28 percent. Disappointing results from Societe Generale SOGN.PA dragged down shares of France's second-biggest bank by 13 percent, compounding fears. also hit shares of U.S. banks, with the S&P financial index .SPSY dropping 2.9 percent. Concerns over profitability in a low-growth, low-interest rate environment have knocked confidence in the banking sector this week, particularly in Europe. declines are coming even as Fed Chair Janet Yellen sought to reassure investors in Congressional testimony that the Fed will remain flexible in its approach. However, the markets already do not expect the Fed to raise rates further this year, compared with Fed forecasts that still point to more tightening.
"The central banks have been taking extraordinary policy actions in the last several years...and now we're seeing that it hasn't been as effective as everyone had been assuming," said Brad McMillan, chief investment officer for Commonwealth Financial Network in Waltham, Massachusetts.
"When you add in the fact that the European banking system is under serious threat right now, you could actually see a path to the kind of systemic crisis that we had in 2008."
Yields on benchmark 10-year U.S. Treasury notes hit 1.53 percent, their lowest level since August 2012, on the worries over global growth and the effectiveness of central bank policy.
MSCI's all-country world equity index .MIWD00000PUS , which tracks shares in 45 nations, was last down 4.92 points, or 1.37 percent, at 353.16.
The Dow Jones industrial average .DJI was last down 312.63 points, or 1.96 percent, at 15,602.11. The S&P 500 .SPX was down 30.51 points, or 1.65 percent, at 1,821.35. The Nasdaq Composite .IXIC was down 50.93 points, or 1.19 percent, at 4,232.66.
Europe's broad FTSEurofirst 300 index .FTEU3 was last down 3.16 percent at 1,202.22.
Oil prices fell amid record U.S. crude inventories, worries about the demand outlook and a Goldman Sachs (N:GS) forecast that prices would remain low and volatile until the second half of the year.
Brent crude LCOc1 was last down 65 cents, or 2.11 percent, at $30.19 a barrel. U.S. crude CLc1 was last down $1.05, or 3.83 percent, at $26.4 per barrel.
Safe-haven asset gold surged to its highest in a year. Spot gold prices XAU= were last up $49.37, or 4.12 percent, at $1,246.48 an ounce.