A three-trailer semitruck hauling toxic materials collided with a passenger car and rolled on 2100 South near 7200 West Thursday, forcing the evacuation of several businesses and closing the road for hours.

Both the car and the semi were westbound on 2100 South about 9:30 a.m. when the driver of the car drifted into the median, then overcorrected while trying to get back onto the roadway, Utah Highway Patrol Lt. Verdi White II said. Her vehicle collided with the semi.The car apparently struck the second trailer, spun around and struck the third trailer, White said. The semi driver hit the brakes, but they locked up, causing the trailers to tip over, White said.

The third trailer was carrying several pipes used in the construction of satellites and containing anhydrous ammonia. The trailer was labled as carrying "poison" and "corrosive" material.

Anhydrous ammonia is combustible and can cause fatal injuries in humans and animals if ingested, asorbed by the skin or inhaled in vapor form.

The driver of the car, Vicki Petty, was treated for minor injuries at Pioneer Valley Hospital. The truck driver was not injured.