A toxic chemical leak at a DuPont plant in Texas that killed four workers and injured a fifth victim was being investigated by a U.S. Chemical Safety Board team on Sunday, the Associated Press reported. The cause of the fatal release, however, remains unknown, DuPont officials said.
The toxic chemical methyl mercepton, which leaked from a valve at a suburban Houston plant, is known to be used in the company's insecticide and fungicide manufacturing process to create crop-protection products, company spokesman Aaron Woods said. It is also used to odorize natural gas - which has no odor - for safety purposes.
On early Saturday, five workers discovered the fatal leak during their normal shift around 4 a.m., and were soon exposed while attempting to contain it over a span of two hours, Woods said.
Soon after being transported to a nearby hospital, four victims died and a fifth one was treated for his injuries and released, ABC News reported.
"Our heartfelt condolences go out to the families of the deceased workers. Our goal in investigating this accident is to determine the root cause and make recommendations to prevent any similar accidents throughout the industry," CSB Chairperson Rafael Moure-Eraso said in a statement.
The La Porte plant, which has about 320 employees working in it, houses four other companies as tenants at the complex.
"There are no words to fully express the loss we feel or the concern and sympathy we extend to the families of the employees and their coworkers," a statement from DuPont said. The company also acknowledged that it would cooperate with "local, state and federal authorities as they conduct a thorough investigation into the accident."
None of the nearby areas were affected by the chemical leak, which according to emergency management coordinator Jeff Suggs caused a smell similar to rotten eggs.
On Sunday, the team from U.S. Chemical Safety Board, an independent federal agency that investigates industrial chemical accidents, arrived in the Houston area to start a probe into the incident, according to a news release, which added that the full team of eight members will begin work Monday.
Meanwhile, Don Holmstrom, director of CSB's Western Regional Office in Denver, is leading the investigation team along with Investigation Supervisor Johnnie Banks. CSB Managing Director Daniel Horowitz is accompanying the team.
Although the CSB is not known to issue citations or fines, it does make safety recommendations to plants, industry organizations, labor groups, and regulatory agencies such as OSHA and EPA.
