Four people were treated and released from a hospital Thursday after becoming exposed to chemical solvents that spilled from a tanker truck onto the street near 90th South and 27th West, officials said.

West Jordan Fire Capt. David Hanney said the top latch of the truck wasn't shut and approximately 100 gallons of solvent "sloshed out" from the truck onto the road when the driver stopped for a red light at 12:14 p.m. Police blocked off all traffic in the area for almost two hours while a response team from National Semiconductor Corp. cleaned up the spill."Our big worry was flammability," said Hanney, who added the situation was not very serious but officials were taking "precautionary measures."

Hanney said two of the four sent to the hospital worked at a gas station near the spill and the other two were in an automobile when they became exposed. A spokeswoman for Holy Cross Jordan Valley Hospital said the victims were showered and released.

The truck belongs to United States Pollution Control Inc., an independent contractor licensed to haul chemicals to disposal sites for National Semiconductor, said Chuck Simoncini, director of human resources and public affairs. The truck had just come from the National Semiconductor plant.

Gary McCuiston, public relations director for United States Pollution Control, said the chemical was a solvent mixture used for degreasing. He called the spill a "very unusual occurrence" and said the company is investigating the incident.

Hanney said the truck driver was cited for driving an unsafe vehicle.