CHENEY -

Concern over a possible toxic spill in the eastbound lanes of I-90 shut down the freeway for six hours Monday morning after a truck carrying 8,000 pounds of toxic chemicals overturned.

The Washington State Patrol shut down the freeway from the Tyler-Cheney Exit all the way to the Four Lakes Exit out of concern the chemicals could be leaking onto the road.

The truck crashed around 5:45 a.m. It was carrying 42 55-gallon drums of sodium hydroxide, a chemical used to make cleaners.

?It can cause chemical burns to the skin, also its an inhalation hazard,? WSP Trooper Troy Briggs said.

Within minutes of the crash something started leaking out of the trailer. The State Patrol shut down the Interstate as Hazardous Materials teams moved in. After several hours they determined the truck was not leaking sodium hydroxide but had spilled some roof sealant the truck was also carrying.

?Well obviously until we found out what we had, and the amount of leakage or spillage, it was definitely an issue,? Trooper Briggs said.

Both eastbound lanes of I-90 were shut down, with a detour that turned the Tyler-Cheney Road into a freeway for six hours.

Eventually one lane was opened but it took almost all afternoon to unload the barrels and get the truck moved.

The State Patrol is investigating why the driver of the truck lost control and crashed; he either went to sleep or had some sort of medical emergency. The State Patrol says its likely he will be cited.