One appliance and crew from Gerrards Cross attended.
One car was in the first lane of a dual carriageway exiting a roundabout, and leaking oil and fluids.
One man was out of the car when they arrived. The firefighters provided immediate emergency care and passed him into the care of South Central Ambulance Service.
The firefighters used an environmental pack to stem the leaking fluids
The incident was left in the hands of Thames Valley Police.