Alcoa, the aluminum company, beat Wall Street earnings estimates on Tuesday night but cut its demand expectation for the year, mostly because of a slowdown in China. Its stock fell 31 cents Wednesday to $8.82.
Chevron, the country's second-largest oil company, warned late Tuesday that slumping oil prices and production would cause earnings to be "substantially lower." It blamed Hurricane Isaac for disrupting production at a Mississippi refinery.
On Tuesday, the Supreme Court also refused to block a $19 billion judgment levied against Chevron by an Ecuadorian court for pollution in the Amazon. Chevron's stock sank $3.21 to $114.13.
The Dow was down 63 points to 13,410 shortly after 10 a.m. Alcoa was the biggest loser among the 30 stocks that make up the average. The Standard & Poor's 500 index fell two points to 1,437. The Nasdaq lost one point to 3,065.
The yield on the benchmark 10-year Treasury rose to 1.74 percent, up from 1.71 percent late Tuesday.
The Dow and S&P 500 are down more than 1 percent for the week. The Nasdaq has lost more than 2 percent.
Toyota Motor Corp. sank 1 percent after the carmaker recalled a total of 7.4 million vehicles worldwide for a for a faulty power-window switch, the latest in a series of recalls for Toyota.
The recall announced Wednesday affects more than a dozen models produced from 2005 through 2010. Toyota's stock dropped 88 cents to $75.18.





