Eleven people have been taken to hospital after coming across barrels containing toxic chemicals on Victoria's southern coastline this afternoon.

The barrels were found this afternoon by two groups of people - one at Harmers Haven, south of Wonthaggi, and the other at the mouth of the Powlett River.

Upon examining the barrels, people from both groups fell ill, Rural Ambulance Victoria spokeswoman Gabrielle Degenhardt said.

Country Fire Authority hazardous materials crews gave the affected people "emergency chemical showers" to decontaminate them, Ms Degenhardt said.

Eleven people were taken to Wonthaggi Hospital - none was believed to be seriously injured.

The origin of the barrels is as yet unknown.