The white dusting covering a Centre Street's Gibbs Gas was from the station's fire suppression system, which let go for unknown reasons on Tuesday evening.
Steve MacDonald of the Boston Fire Department said there wasn't a blaze at the 581 Centre St. gas station.
He said there were no injuries. The extinguishing agent is a derivative of baking soda, MacDonald said.
The Fire Department said the gas station is looking into why the system triggered.