Stock index futures pointed to a lower open on Monday as Chinese equities dropped sharply and commodities fell on concerns that asset prices have run ahead of the economic realities.

S&P 500 futures fell 6.5 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures lost 60 points and Nasdaq 100 futures dropped 12.50 points.

I think that what we are facing here is a worried market ... we've had such a nice rise here that everyone is talking about pullback, said Peter Cardillo, chief market economist at Avalon Partners in New York. What is happening in the Chinese market is increasing that wall of worry.

The Shanghai Composite Index <.SSEC> lost 6.7 percent and dropped to below its 125-day moving average, which many domestic investors believe is the dividing line between bear and bull markets. The index is still up 47 percent year to date.

Oil dropped 2.3 percent, falling near $71 a barrel as traders fretted about a sharp decline in Chinese stocks, while metal prices were also off, with Shanghai copper retreating after recent strong gains.

Japan's Nikkei <.N225> average fell 0.4 percent as a stronger yen sent exporter shares lower, erasing an earlier jump to an 11-month high, and after a landslide victory by an opposition slate.

European shares were down, dragged lower by banks and resource-related shares, such as Credit Suisse and ArcelorMittal , but volumes were low as U.K. markets were closed for a holiday.

In takeover news, oilfield service company Baker Hughes Inc said it would buy BJ Services Co for $5.5 billion in stock and cash. The deal represents a premium of 16 percent over BJ's closing price of $15.43 on Friday. The shares rose 13.4 percent to $17.49 before the bell.

A regional survey is expected to show manufacturing in the Midwest performed better in August than the previous month. Economists in a Reuters poll forecast that the Chicago PMI index rose to 48 points in August from 43.4 points in July. The report is due at 9.45 a.m. EDT.

U.S. stocks mostly slipped on Friday after a weak consumer sentiment report offset positive news from bellwethers Dell Inc and Intel Corp . Support from the two companies, however, let the Nasdaq eke out a tiny gain.

(Reporting by Edward Krudy; Editing by Jeffrey Benkoe)