Crude oil prices fell after some downbeat economic reports pointed to a deeper recession in the United States, which would push energy demand down.
Traders also expect a U.S. government report to show continued growth of oil inventories in the world's biggest energy market.
The price of a barrel of oil for future delivery fell more than $4 to hit $41.67 at the close of trading in New York.
Oil has fallen as low as $33 a barrel recently, and hit an all-time high above $147 a barrel last July.
Some information for this report was provided by AFP, AP and Reuters.