Concerns about corporate earnings amid deteriorating world economies sent North American stock markets sharply lower Wednesday morning.

The Toronto S&P/TSX composite index retreated 253.9 points or 2.5% to 9,548.4 in early trading, after lower energy and financial stocks provoked a 456-point tumble yesterday.

On Wall Street, the Dow Jones industrial average fell 199.4 points to 8,834.2 after losing 232 points in the previous session.

The Canadian dollar slipped under US80¢ Wednesday morning, pulled down by overall economic fears and falling commodity prices.

The loonie traded down to US79.80¢, pulling up later to US80.08¢, still down 2.31¢ on the morning, after dropping 1.38¢ yesterday.