The Bhopal disaster
The world's worst industrial disaster: the 1984 Bhopal gas tragedy.
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On 3 December 1984, over 500,000 people near the Union Carbide India Limited (UCIL) pesticide plant in Bhopal, India, were exposed to the highly toxic gas methyl isocyanate (MIC), marking the world’s worst industrial disaster. The plant, built in 1969, produced the pesticide Sevin using MIC as an intermediate; an MIC production unit was added in 1979. The process involved reacting methylamine with phosgene to form MIC, which was then combined with 1-naphthol to create carbaryl.
Unlike some other manufacturers who later adopted MIC-free routes, UCIL continued using this method, leading to an accumulation of unused MIC as pesticide demand fell in the early 1980s. The facility housed three underground 68,000-liter MIC storage tanks. By late October 1984, tank E610 lost its ability to maintain nitrogen gas pressure, trapping 42 tons of liquid MIC.
Production was halted for maintenance, during which the plant’s flare tower—a critical safety system—was shut down for pipe repairs. Despite the inoperable flare tower, carbaryl production resumed in late November using stored MIC. Prior to the disaster, the plant had a history of leaks: in 1981, a worker died from phosgene exposure; in 1982, leaks of phosgene and MIC affected dozens of workers; and throughout 1983–1984, multiple leaks of MIC, chlorine, and other toxic gases occurred. The 1984 leak caused approximately 558,125 injuries, including 38,478 temporary partial injuries and 3,900 severe permanent disabilities.
Official immediate deaths numbered 2,259, though estimates suggest 8,000 died within two weeks, with thousands more later succumbing to gas-related diseases. Union Carbide Corporation (UCC) of the U.S., which owned 50.9% of UCIL, paid $470 million in 1989 to settle litigation. In 2010, seven former UCIL employees, including chairman Keshub Mahindra, were convicted of negligence and sentenced to two years’ imprisonment.
Lore & Background
The UCIL factory was built in 1969 to produce the pesticide Sevin using methyl isocyanate (MIC) as an intermediate. An MIC production plant was added in 1979. In the early 1980s, demand for pesticides fell but production continued, leading to an accumulation of unused MIC. The facility housed three underground 68,000-litre liquid MIC storage tanks.
In late October 1984, tank E610 lost the ability to contain nitrogen pressure and held 42 tons of liquid MIC. On 2–3 December 1984, water entered tank E610, causing a runaway exothermic reaction. About 30 tonnes of MIC escaped from the tank into the atmosphere in 45 to 60 minutes. Safety systems including a refrigeration system, flare tower, and vent gas scrubber were malfunctioning or inoperable.
Common Misconceptions (Editorial)
Some people mistakenly believe the Bhopal disaster was solely the fault of the parent company, Union Carbide Corporation (UCC), but the facts show the plant was operated by Union Carbide India Limited (UCIL), though UCC was the parent company. Another common misconception is that the leak was a sudden, unforeseeable event; in fact, the facts indicate that safety systems such as the refrigeration system, flare tower, and vent gas scrubber were malfunctioning or inoperable prior to the leak, and tank E610 had already lost its ability to contain nitrogen pressure, making the disaster foreseeable.
Why It Matters (Editorial)
The Bhopal disaster endures as a stark reminder of the catastrophic consequences when industrial safety is neglected in pursuit of profit. Its legacy continues to shape global environmental and chemical safety regulations, underscoring the urgent need for corporate accountability and the protection of vulnerable communities from industrial hazards.
Reader's Guide
The disaster resulted in approximately 558,125 injuries, including 38,478 temporary partial injuries and 3,900 severely and permanently disabling injuries. The official number of immediate deaths is 2,259, though estimates vary; some say 8,000 died within two weeks and another 8,000 or more from gas-related diseases.
In 1989, Union Carbide Corporation paid $470 million to settle litigation. In June 2010, seven former UCIL employees were convicted of causing death by negligence and sentenced to two years' imprisonment and a fine of about $2,000 each. An eighth former employee was also convicted but died before judgement.
Did You Know?
- The owner of the factory, Union Carbide India Limited, was majority-owned by Union Carbide Corporation of the United States.
- Dow Chemical Company purchased UCC in 2001, seventeen years after the disaster.
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Sources
Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.
- Wikipedia: Bhopal disaster (CC BY-SA 4.0).
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