Crude oil loads carried by U.S. railroads last year grew 83 percent over 2012, the AP reported.
“The Association of American Railroads said Thursday the major U.S. railroads delivered 434,042 carloads of crude oil in 2013.”
In 2012, 236,556 carloads of crude oil were delivered by railroads.
In 2008, only 9,344 carloads were delivered, the AP said.
The U.S. Department of Transportation issued emergency rules last month that require tests on crude oil shipped by rail, saying rail transport of crude is now “an imminent hazard to public health and safety and the environment.”
The Transportation Department said the order is aimed at Bakken crude but will cover shipments from anywhere. Bakken shale oil is light and more volatile than most other North American crudes.
Last July, a derailment and explosion of a train carrying Bakken crude killed 47 poeple in Lac-Megantic, Quebec.
Last month federal regulators and the rail industry announced new voluntary measures to make transporting crude safer.
The measures included lower speed limits in urban areas, re-routing trains around population centers, and better access to emergency braking systems by crews.
A series of derailments in the U.S. following the Quebec disaster highlighted the growing dangers of the rail shipments.
Several companies have also said they would voluntarily upgrade their tanker fleets to improve safety.