Around 80 car batteries fell off the back of a lorry causing corrosive sulphuric acid to spill out onto the road.
The incident happened on Doncaster Road close to the Cathill Roundabout in Darfield, Barnsley, at 11pm last night.
Two fire crews from Dearne Station were called to clear up the toxic mess.
The road was sealed off for about four hours while they made the scene safe.
A spokesman for the station said: "Our crews had to wear breathing apparatus due to the toxic nature of the spill.
"We put sand on it and then when it soaked it up we were able to wash it away.
"The spill was in two locations near the roundabout."
He said the driver was unhurt and police are investigating the cause.