Carbide Halting Output of Pesticide in Gas Leak : Computer Not Set Up to Track Chemical
Union Carbide Corp., still seeking to resolve a number of questions arising from a chemical leak that made hundreds of area residents ill, announced Tuesday that it has suspended production of the highly toxic pesticide aldicarb.
Also, the company acknowledged that its computerized safety system never was programmed to track the chemical that leaked Sunday, aldicarb oxime. “I am sure if we had used the system correctly it would have worked better,” spokesman Thad Ebbs said. “We substituted a chemical with close to the same components. We got reasonably good programming.”
Aldicarb oxime is a raw ingredient used in making aldicarb. Although the company has ranked the potential adverse health effects from aldicarb oxime in its most serious category with those of MIC (methyl isocyanate)--which escaped last December from an almost identical plant in Bhopal, India, killing 2,500--it insisted that the chemical is only one-tenth as lethal as MIC.
Meanwhile, a non-toxic chemical leaked Tuesday night into the air and into the Kanawha River at Union Carbide’s South Charleston plant five miles away. The chemical “stinks like the dickens” said State Police Cpl. D. E. Cook. By 10 p.m., the leak had been contained and there were no reports of injuries or illnesses.
“It is very unfavorably aromatic, but it is not toxic,” Cook said.
The condition of one of the 14 persons still hospitalized because of the fumes emitted Sunday deteriorated Tuesday from stable to serious. The woman, who was not identified, has a history of respiratory problems, Kanawha Valley Memorial Hospital spokesman Clinton Dailey said.
A total of 135 persons sought treatment at five local hospitals, and 31 were admitted. Hundreds of others, complaining of minor eye, skin and breathing irritation, received medical help at an emergency center.
The Institute plant came under intense scrutiny after the Bhopal disaster because it is this country’s only producer of MIC. In response, the company installed $5 million in new safety equipment.
Top-ranking federal officials toured the plant site Tuesday as part of the government’s own investigation to determine what happened and whether Union Carbide acted as quickly as it should have to notify the surrounding area that it was in danger. Outraged residents of nearby communities have charged that the company did not alert them soon enough.
Environmental Protection Agency Administrator Lee M. Thomas inspected the plant for several hours with Senate Minority Leader Robert C. Byrd (D-W. Va.), Patrick Tyson, acting director of the Occupational Safety and Health Administration, and other government officials. But Thomas told reporters that he would wait for results from the agency’s more detailed evaluation before passing judgment on Union Carbide’s actions.
Chemical Put in Reactor
The accident is believed to have happened because steam entered a jacket surrounding a tank containing 500 gallons of aldicarb oxime and another chemical, dichloromethane, and overheated the mixture, building up too much pressure. The pressure grew so intense that it could not be contained by an emergency vent system, and a device known as a rupture disc opened, discharging the chemical into the atmosphere. Union Carbide would not say whether the steam was intentionally introduced.
Epps acknowledged that the chemical was being held in a chemical reactor, rather than an ordinary storage tank. Although this is not “normal, everyday” procedure, he said, it also is “not unheard of.”
The accident occurred in a small unit that was being phased out for aldicarb production as a larger one was being put into operation.
Epps, disputing reports that aldicarb oxime is as toxic as MIC, said that tests on laboratory animals showed it was only one tenth as lethal.
“Every indication we have is that there will be no residual effects from exposure to aldicarb oxime,” he said.
Dr. Vernon Houk of the Centers for Disease Control, who was touring the plant with the other government officials, agreed that he expects “no long-term toxicity” but said his agency had advised residents not to eat vegetables grown in the area covered by the gas cloud Sunday until the CDC studies the issue further.
Controversy over whether Union Carbide alerted residents quickly enough continued as the area’s congressman, Rep. Bob Wise (D-W. Va.), released the results of his staff’s door-to-door survey of 254 households near the plant. More than half of the persons surveyed said that they had learned of the leak by seeing or smelling it--that is, by being exposed to the chemical, rather than by hearing the siren that was supposed to alert them to it.
More than one fifth of the respondents said that they realized something was wrong at the plant before the time that Union Carbide officials said they learned of the release.
Company officers had said earlier that their computer tracking system originally did not indicate that the 15-minute leak--which formed a cloud several hundred yards wide--would go beyond the boundaries of the sprawling chemical complex. Because of that belief, and their concern for rescuing six workers in the unit, they did not alert county officials to the danger for 19 minutes, they said.
