Negligence by the Union Carbide and not sabotage was responsible for the Bhopal gas disaster, the British journal New Scientist said on Thursday basing its conclusion on documents just released in the United States.
"The documents suggest the owner of the chemical plant cut crucial corners in its design, and reduced investment to maintain control," the journal said in a leading article.
This compromised safety of the plant, it added.
The accident at Union Carbide's pesticide plant in Bhopal in 1984, the worst industrial disaster on record, killed 8000 people and injured at least 150,000. The victims are still dying.
The company paid $470 million as compensation to a trust in 1989. The survivors received around $500 each. The report said Union Carbide, now taken over by Dow Chemical, was forced to release the documents last month by a court in New York state that was hearing a class action suit filed by Bhopal survivors in 1999.
The internal documents contradict earlier claims of the company that the accident was an act of sabotage and not due to faulty design, New Scientist said.
According to the report, Union Carbide, in order to retain control of its Indian subsidiary decided to reduce the amount of investment to $20.6 million instead of $28 million. "This meant using unproven technologies," the report said.
The company's 1972 memo further revealed that the Sevin pesticide production system involved in the accident had "only a limited trial run", the report said.
New Scientist said its investigation of the accident, and subsequent studies by the company and trade unions, showed that a faulty valve let nearly a tonne of water being used to clean pipes pour into a tank holding 40 tonnes of Methyl Isocyanate (MIC), an intermediate in the production of Sevin.
The resulting runaway reaction produced a cloud of toxic gas. "Regardless of how the water got into the MIC, the runaway reaction should have been contained," the article said. "It was not, largely because Bhopal had far more limited emergency equipment than Carbide's US plant."
Crucially, Bhopal had no "knock-down" tank where the mass of chemicals that boiled out of the MIC tank might have settled. Then only gases would have escaped, which could have been burnt off by flare towers or by filtered out by a "scrubber". But the Bhopal plant had only one flare, shut for repairs on the night of the accident, the report said.
The US plant had a back up. Bhopal's sole scrubber was overwhelmed by the mass of liquids and gases that boiled up at a rate over 100 times what it was designed for. Also unlike the US plant, Bhopal's waste was poured into open lagoons to evaporate.
Recent analyses of groundwater, soil and the people near the plant have found high levels of heavy metals such as mercury and toxic organochlorine chemicals.
According to New Scientist, Carbide's 1972 memo specified that the US headquarters would either perform all design work for the plant, or approve designs done elsewhere. The report said that on the basis of fresh evidence, the US company could be tried for negligence only if the Indian government joined the campaigners in the US lawsuit.