A tank at a glycol processing unit at Dow Chemical's plant in Iberville Parish exploded with a loud boom Sunday morning, shaking homes and rattling windows in nearby Plaquemine but causing no injuries, officials said. The tank, or vessel, contained water and small levels of sulfuric acid, ethylene oxide and nitrogen, which are used for a variety of manufacturing purposes, said Dow spokeswoman Ashley Mendoza. The company began testing "within minutes" after the explosion, she said and detected no harmful material in the air in and outside of the 1,500-acre facility just outside of Plaquemine. Iberville Sheriff Brett Stassi said aside from the startling boom that rumbled neighborhoods near the plant, including his own home, no one was injured. The company said crews stabilized the tank, or vessel, shortly after it burst.