Carbide Halting Output of Pesticide in Gas Leak : EPA Apparently Not Told of Health Peril
Union Carbide Corp. officials apparently did not inform the Environmental Protection Agency of health hazards posed by aldicarb oxime, although the firm had laboratory evidence that the chemical potentially could cause major injury.
The apparent lapse raises questions about whether Union Carbide obeyed a federal law requiring immediate disclosure to the EPA whenever a chemical is found to pose a significant risk of human injury, according to two EPA officials who asked not to be named.
The law, the 1976 Toxic Substances Control Act, is designed to give the EPA and other federal agencies advance warning of chemical hazards that merit new environmental or safety controls.
The chemical injured 135 persons after leaking Sunday from the company’s factory in Institute, W. Va.
Union Carbide’s own internal ratings show aldicarb oxime “can produce major injury” when accidentally released. The firm said Tuesday that animal tests indicate it is highly toxic, albeit only one-tenth as toxic as methyl isocyanate, the chemical that killed 2,500 persons last December in Bhopal, India.
However, EPA officials said Tuesday that they were unaware of those studies. The only information in agency files are 1974 studies, financed by Union Carbide, that show the chemical is mildly toxic when fed to laboratory animals.
“I think that is all the information that is available,” said Bruce Jaeger, a toxicologist in the EPA’s pesticide and toxic substances division. “The only other repository for such information would be Union Carbide.”
One agency expert said that “it sounds to me like something they should have reported” to the EPA.
EPA officials consider failure to report hazards a serious violation of the toxic substances act. Last March, the agency fined Union Carbide $3.9 million--the largest penalty of its type--for a “clear violation” of the notification rules after the company waited four years to turn over evidence that one of its chemicals causes cancer in laboratory animals.
A Union Carbide spokesman in the company’s Danbury, Conn., offices said Tuesday that the firm stands by earlier statements that aldicarb oxime is a severe eye irritant that does not pose major health threats. He said also that the firm does not make the chemical but purchases it from Allied Corp., another major chemical maker.
However, the fact that the chemical is made by another firm does not free other processors from the responsibility of informing the EPA if they discover that the substance poses health hazards.
Union Carbide spokeswoman Mary Ann Ford in Research Triangle Park, N.C., said late Tuesday that the latest toxicity estimates were based on combined results of four studies conducted between 1967 and 1984. She did not say whether the 1984 study was reported to the EPA.
The reporting issue seems certain to fuel an expanding debate in Institute and in Washington over whether Union Carbide executives have fully disclosed what the firm knows, both about aldicarb oxime and about the accident Sunday. Company spokesmen have tried to minimize the scope of the accident, calling it at one point “a little leak” of a moderately toxic eye irritant.
The company since has come under blistering attack from federal and local officials as evidence mounted that aldicarb oxime is more hazardous than first suggested and that Union Carbide did not respond as quickly to the leak as originally indicated.
Rated Highly Toxic
“This leak was 180 times smaller than the one at Bhopal, and look at the damage it did,” said an aide to Rep. Henry A. Waxman (D-Los Angeles).
Aldicarb oxime’s health hazards have been the subject of a welter of sometimes-conflicting pronouncements from Union Carbide spokesmen and information from company documents.
The firm’s 1983 guidelines give the gas a hazard rating of 4 on a scale of 1 to 4, the same as MIC and phosgene. So-called “Rating 4” chemicals include those that are “predominantly fast-acting and can produce major injury.”
Although not denying that rating’s accuracy, Union Carbide spokesmen have tried to play its importance down. They said that the “4” rating merely “indicates that all due precaution must be taken” and said aldicarb oxime was given a high rating mainly because it is “a severe eye irritant.”
However, after the company released a summary of laboratory tests that showed aldicarb oxime to be one-tenth as toxic as MIC, EPA officials said they were unaware of the tests--which suggest that the chemical’s gaseous form is far more toxic than the agency previously believed.
Nor could aides to Waxman find the test results in the National Library of Medicine, which maintains a regularly updated data bank on toxic substances.
Although the toxic substances act generally governs routine chemical uses, a clause covering “emergency incidents” requires notification of any chemical hazard that, “because of the pattern, extent and amount of contamination, seriously threatens humans with . . . death or serious or prolonged incapacitation.”
