Four workers died after a dangerous chemical leak at a DuPont plant in La Porte, Texas early Saturday morning. A spokesman for the plant told reporters that a valve "somehow failed" on a container of methyl mercaptan, a chemical used to make insecticide.
All four employees died on the scene; one additional plant worker has been hospitalized, and is expected to make a full recovery. Among the killed were brothers Robert Tisnado, 39, and Gilbert Tisnado, 48. "For us it was a double whammy," Gilbert Tisnado, their father, told the Houston Chronicle. "They died on the same shift in the same unit."
Wade Baker, 60, the crew's supervisor, also died in the chemical leak; another woman who had worked at the plant just eight months died as well.
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The chemical, methyl mercaptan, is used to give natural gas its rotten-egg smell. Symptoms of exposure include severe respiratory, skin and eye irritation. It can also cause headaches, dizziness, nausea, vomiting, coma and death, especially when exposure occurs in poorly ventilated, enclosed or low-lying areas, according to the Agency for Toxic Substances and Disease Registry.
KHOU reports the leak occurred around 4 a.m. local time Saturday, and was eventually contained at around 6 a.m. In those two hours, the five employees were exposed to the chemical. Aaron Woods, the plant's spokesman, told the TV station that surrounding areas were safe from the chemical, saying that "once it goes into the air, it dissipates to the point where it is no longer hazardous."
The U.S. Chemical Safety Board announced Saturday that a seven-person investigative team has already been dispatched to the plant. "It's a toxic material. It's on multiple lists. It commands the highest level of regulatory scrutiny, so when there are this many deaths associated with a chemical like that it raises all sorts of questions," Daniel Horowitz, the agency's managing director, told the Houston Chronicle.
Four DuPont locations have been investigated by the agency since 2010.
"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 co-workers," plant manager Randall Clements told KHOU. "We are in close touch with them and providing them every measure of support and assistance at this time."