DuPont uses ammonia as a raw material for many of its products. It provides the source of nitrogen used in making various Belle plant chemicals.
Most people are familiar with the ammonia they use as a household cleaner. Unlike those cleaners, ammonia used at the Belle plant is not heavily diluted with water.
Exposure to ammonia can cause burning, swelling of the larynx, severe pulmonary and gastrointestinal irritation, nausea, vomiting, convulsions and, in large enough doses, coma and even death.
Hastings said DuPont did not detect any ammonia odors at ground level on the site and was not aware of any reported odors offsite.
"We are continuing our investigation to finalize our calculations on the quantity released and determine the cause of the leak," Hastings said.
The U.S. Chemical Safety Board is investigating a series of incidents at the DuPont plant in early 2010, including the Jan. 23 phosgene leak that killed a worker. The CSB will release its report in early April, said agency spokeswoman Hillary Cohen.
Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.