Nine workers and two paramedics are in hospital after a container of nitric acid overturned at a landfill site.
The 11 were taken to Queen Margaret Hospital in Dunfermline by ambulance because they were exposed to fumes from the liquid.
Ten have since been discharged while one has been admitted but is not said to be giving cause for concern.
The spill from the 10-litre container happened in a materials recovery facility at Lochhead landfill site near Dunfermline, Fife.
Emergency services were called to the scene at around midday. The council-run site was evacuated and kept closed for around four hours but was later reopened.
Fife Council's Michael Enston said: "No members of the public have been injured during this incident and all of the emergency services have been present.
"The landfill site was closed and the area evacuated as a precaution, with all landfill operations suspended. Lochhead has now reopened but the materials recovery facility remains closed until decontamination procedures have been completed.
"Investigations into the incident will be carried out over the next few days."
The Scottish Ambulance Service sent two ambulances and a specialist operations team to the scene and officers from Fife Constabulary were also there.
A spokeswoman for Fife Fire and Rescue Service said: "We had four appliances and an emergency support unit at the scene."