*TSX down 0.77 percent at 12,017.44
*Energy, financials lead index lower
*Shoppers Drug Mart plunges almost 10 percent
By Claire Sibonney
TORONTO, April 8 (Reuters) - Toronto's main stock index was sharply lower on Thursday morning as a triple whammy of weaker commodity prices, persisting euro zones worries and a rise in U.S. jobless claims hit stock markets around the world.
Also hurting the index, shares of Shoppers Drug Mart SC.TO, Canada's biggest drugstore chain, plunged more than 16 percent as investors assessed the fallout from Ontario's plan to reduce generic drug prices. [ID:nN08178007]
On the commodities side, oil declined for a second day towards $85 a barrel and natural gas futures also traded lower, sending oil and gas producers down more than 1 percent. [O/R] [NATGAS]
Shares of Athabasca Oil Sands Corp (ATH.TO), Canada's biggest initial public offering in more than a decade, dipped to C$17.65 in their debut on the Toronto Stock Exchange, below their pre-market price of C$18. [ID:nN08142063]
At 10:23 a.m. (1423 GMT), the Toronto Stock Exchange's S&P/TSX composite index .GSPTSE was down 93.46 points, or 0.77 percent, at 12,017.44. All 10 sectors were down.
On Monday, the index hit 12,203.39, its highest level since September 2008.
Also undermining the market on Thursday were persisting worries over Greece's public finances and sovereign debt defaults in Europe as well as data that showed a rise in U.S. workers filing new claims for unemployment insurance last week. [ID:nLDE6370QK] [ID:nN08324871]
"The pattern seems for the last few days that we come down and then we try to rally back up, we don't quite make it to the zero line but we'll see if it happens today," said Ian Nakamoto, director of research at MacDougall, MacDougall & MacTier.
"Perhaps we've just had a nice run in Canada. Time to take a little bit of profits."
Materials were off 0.6 percent as copper prices dropped nearly 2 percent to a one-week low, although gold prices were firm. [MET/L] [GOL/]
Barrick Gold Corp (ABX.TO), the world's largest gold producer, added 0.5 percent to C$41.09, while miner Teck Resources TCKb.TO fell 2.1 percent to C$44.47.
$1=$1.01 Canadian Reporting by Claire Sibonney, editing by Peter Galloway