An oilfield chemistry facility owned by Berkshire Hathaway Inc.’s Lubrizol Corp. was destroyed by a fire on Tuesday in Southwest Pennsylvania. Eight people, including firefighters and Lubrizol employees, were treated for non-life threatening injuries.

More than 20 fire departments, four emergency management agencies, two local hazardous materials teams and state regulators responded to the blast, which occurred about 10 a.m. EDT at the facility in Leetsdale Borough about 19 miles northwest of Pittsburgh. The fire was under control by 2 p.m. EDT.

Officials said they were not sure what caused the fire. The Allegheny County Fire Marshal’s Office and Lubrizol are investigating. County officials said it would likely be several days before any more information is released.

The county reported that two buildings caught fire and six others in the industrial park were threatened. First responders evacuated 72 homes and business parks in the area with an order that was lifted by early in the evening. Officials said one building was a total loss and had collapsed, while a second incurred significant fire and water damage.

The Pennsylvania Department of Environmental Protection said initial reports found no issues with air quality levels. Two chemicals — ammonium persulfate and sodium chlorite — were released during the blaze.

Berkshire bought Lubrizol in 2011 and last December it acquired oilfield chemicals businesses from Weatherford International plc for $750 million, including the buildings involved in the fire (see Shale Daily, Dec. 1, 2014). The company blends chemicals for oilfield applications, including additives and fluids for cementing, drilling, flow assurance and hydraulic fracturing.