Merseyside Fire & Rescue Service was called at 12.38pm on Tuesday, February 26, to a building in Grange Road, West Kirby.
Two fire appliances were initially sent to the scene and found an estimated five litres of the substance had spilt.
Two males were checked by paramedics at the scene.
Firefighters wearing gas tight suits entered the area of the spill as part of measures to identify the substance.
Group Manager Chris Case said: “Two specialist officers, wearing protective equipment, have also entered the area with gas monitoring equipment to identify the substance.
“Adjoining premises have been evacuated as a precautionary measure. Everyone from businesses, local people and emergency services have been very co-operative and we are very thankful for that.”
The road was closed to allow emergency services to operate.
Two shops and pub have been evacuated and residents in the nearby area were informed to keep windows and doors shut as a precaution.
Officers from the Detection, Identification and Monitoring (DIM) team, based at the Operational Resource Centre at Kirkdale Community Fire Station, investigated the substance.
Group Manager Chris Case said: “Our equipment showed there were no dangerous gases being released in the area or from the spilt substance. The substance has dissipated naturally and the cordon, which was put in place, has been lifted. There is no cause for concern for local people.