Northbound traffic on Interstate 65 near Columbia was rerouted off the interstate for several hours Tuesday morning after a tanker truck overturned.
The tanker containing liquid argon gas rolled off the exit ramp to Highway 412 just before 5 a.m.
Two people inside the truck were taken to Vanderbilt University Medical Center for treatment.
All lanes were shutdown and traffic was rerouted off the interstate at mile marker 46.
By about 9:30 a.m. at least one northbound lane had reopened.
Argon is not toxic but can displace oxygen and is considered dangerous if leaked in contained spaces.
Hazmat officials said crews had to wait for the gas to burn into the atmosphere before moving the tanker.
All lanes of I-65 North have since reopened although the exit ramp to Highway 412 remained closed Monday evening.