Foam release blocks two lanes of SB I-55 at Potomac

ST. LOUIS, Mo. - There's an unusual looking mess along southbound Interstate 55 at Potomac Street in south St. Louis. Non-toxic foam made its way onto the pavement.

A fire alarm at the nearby Sigma-Aldrich plant sounded when it was released from the building. Part of it blocked two lanes on I-55.

MoDOT crews used a plow to clean the mess.

St. Louis-based Sigma-Aldrich produces chemical products used in manufacturing and research.