The Dow was down 123 points, or 0.8 per cent, to 15,285 as of noon (1600 GMT) Wednesday.
The S&P 500 index fell 13 points, or 0.8 per cent, to 1,647. The Nasdaq composite dropped 23 points, or 0.7 per cent, to 3,465.
The yield on the 10-year Treasury note edged down to 2.16 per cent from 2.17 per cent late Tuesday.
The yield surged Tuesday to its highest level in 13 months as investors moved out of bonds on concern that the Federal Reserve plans to start easing back on its bond purchases.
Smithfield Foods surged 25 per cent after the company agreed to be acquired by a Chinese meat processor, Shuanghui International, for $4.7 billion.