A delivery truck lost a pallet of paint outside a shop on Friday morning after a lifting belt broke, and 440 liters (116 gallons) of white paint ran into the Oslo river.
"We have been told that the river is quite white. We are now out gathering water samples now," said Hanne Tomter of Oslo's Department of Water and Sanitation.
Tomter was unsure what the effects of the water soluble paint on river wildlife would be.
"The fish are vulnerable and we assume that we will be notified by the public if fish die," Tomter said. She had no idea if the paint posed a risk to humans, but said that this was hardly the time of year for people to be wading in the river.
