U.S. stocks fell, with raw-material shares dragged lower as commodities retreated, a selloff in biotechnology shares deepened and Volkswagen AG’s diesel-emissions cheating scandal continued to rattle global auto stocks.

Fiat Chrysler Automobiles NV fell 6.2 percent, while Ford Motor Co. and General Motors Co. lost at least 2.8 percent. Dow Chemical Co. and Alcoa Inc. dropped more than 1.3 percent amid sliding commodity prices. The Nasdaq Biotechnology Index sank 2.9 percent after losing 4.4 percent Monday. Apple Inc., Google Inc. and Facebook Inc. declined at least 1.9 percent.

The Standard & Poor’s 500 Index lost 1.4 percent to 1,939.39 at 12:22 p.m. in New York, after rising 0.5 percent yesterday. The Dow Jones Industrial Average slid 216.33 points, or 1.3 percent, to 16,293.86. The Nasdaq Composite Index slumped 1.8 percent. A gauge of volatility was headed for its biggest gain in a month.

Source : Bloomberg