Local news source KMOV.com reported an incident that occurred on Wednesday, July 10 in northern St. Louis County. What was identified as an acid spill injured three and resulted in the evacuation of Hazelwood East High School.
Authorities evacuated all students and faculty from the building, as well as a construction crew working inside at the time. All students were relocated to the nearby Kirby Junior High School. While there, two students and a construction worker began feeling ill from inhalation of the chemicals. All three were transported to a nearby hospital in unknown condition.
The cause of the odor was discovered by HazMat crews as muriatic acid that leaked out from a hose that came loose. The tank of muriatic acid was in a pump and supply room next to the pool in the school. This type of acid is used to keep the pH level of the pool water at a correct level if there is too much chlorine in the water.
Muriatic acid is commonly referred to as hydrochloric acid. It is also used in small amounts for food additive, gelatin production, descaling, leather processing, household cleaning (when diluted), pickling of steel, production of inorganic compounds, building construction, and purification of table salt.
Only a small amount of acid spilled out of the hose in the school, but it produces such a strong odor that it was enough to make individuals who inhaled it sick. Officials began airing out the building an hour before crews arrived to clean up the chemical.
See video, pictures, and more information on this acid spill in northern St. Louis County here.