The Bhopal Tragedy
On the night of the 2-3rd December 1984, Bhopal, capital city of Madhya Pradesh in India, witnessed one of the most horrifying Industrial disasters; the Bhopal Gas Tragedy or the Bhopal Disaster. This happened due to a toxic gas leak at the Union Carbide India Limited’s (UCIL) pesticide plant in Bhopal – killing over 3,000 people immediately and a claim of over 20,000 lives since then.
This deadly methyl isocyanines poison gas leak at the plant in 1984 continues to bring suffering, health hazards, and dangerous environmental conditions even at this present time. Union Carbide India Limited (UCIL) is a subsidiary of the U.S.A-based Union Carbide Corporation (UCC) and the UCC owned 51% stake in the UCIL.
UCIL’s plant’s main objective was to create a pesticide/insecticide Carbaryl under UCC’s brand, using MIC as an intermediate. MIC is a flammable, dangerous and toxic substance used also in the manufacturing of rubber. MIC is extremely hazardous to the human health.
Companies like Bayer also manufactured Carbaryl. However, they did it without the use of MIC – at an extra manufacturing cost. Even today, some other companies, including Bayer, still use the UCC process of making Carbaryl.
The chemical process initiated in the Bhopal plant consisted of using methylamine with phosgene to form MIC, which then reacted with napthol to form the final product; carbaryl.
This “route” differed from the MIC-free routes used elsewhere, in which the same raw materials were combined in a different manufacturing order. Phosgene first reacted with naphthol to form a chloroformate ester, which then reacted with methylamine.
During the early 1980s, there was low demand for pesticides. However, UCIL continued to manufacture Carbaryl, which led to an excess build-up in the MIC stock.
Starting from 1976, two workers complained about pollution inside the plant. In 1981, a worker was splashed with phosgene. When he removed his mask in a panic, he ended up inhaling large amounts of phosphene gas. He died 72 hours later. Following this, American experts visited the plant in 1981 and warned the UCC about a “runaway reaction” in the MIC storage tank. Local Indian Authorities also warned UCIL about the same problem. However, no preventive measures or precautions were taken by UCIL or UCC.
Jan 1982 – 24 workers were exposed to Phosgene leak. They were admitted to the hospital because the company had not regulated the wearing of safety masks.
Feb 1982 – MIC leak affects 18 workers
Aug 1982 – A Chemical Engineer suffered burns on 30% of his body after coming in contact with MIC.
Oct 1982 – In an attempt to stop another MIC leak, the MIC Supervisor suffered severe chemical burns and two other workers were severely exposed to the gases.
This continued from 1983 to 1984 – where different chemicals leaked and continued to cause damage to workers, people around them, and the surrounding areas. The company also filled and stored MIC beyond recommended levels with no maintenance. After they stopped producing MIC, there were failures of safety systems due to poor maintenance and, shockingly, the SWITCHING OFF of safety systems to save money. The MIC tank refrigeration system that was turned off could have drastically subdued the gas leak.
There was also a motive to cut down expenses at the plant. During the event of a pipe cut, the employees were advised not to replace it. Apparently, the UCIL also assumed that workers needed minimal to no training. They stopped promotions workers – which hurt morale – and in turn drove skilled workers to other places. Workers were asked to use English manuals, even though they were barely literate in the English language.
By 1984, only 6 out of the 12 operators were still working. During night shifts, there was no maintenance supervision, and instrument readings were taken every 2 hours, instead of every 1 hour. Although workers complained to the Union, the company ignored them. In fact, the company fired a worker who went on a 15-day hunger strike. The UCIL also fined 70% of the employees for refusal to deviate from the regular safety norms under management pressure.
The MIC tank alarms had not been working for 4 years – leaving one back up system, in comparison to the 4-stage backup process used in UCC, USA.
The Flare tower and vent gas scrubbers were out of service for 5 months before the disaster. Since just one gas scrubber was operating, it could treat the high amounts of MIC.
The flare of the tower could only handle a quarter of the gas that leaked in 1984. Furthermore, it was out of order during the time of the incident.
Although the steam boiler was operational, a lot of the equipment did not work. Shockingly, Carbon Steel valves were used in the factory, although it is known to corrode when exposed to Acids.
The MIC gas was supposed to be kept at 4.5 degrees Celsius, however, it was kept at 20 degrees Celsius.
After the inquiry was examined, they found out that the UCIL was using a very dangerous pesticide manufacturing method to save money, large-scale MIC storage, and undersized safety devices. The poor plant management also included; reduction of safety management, lack of skilled operators, insufficient maintenance, and inadequate emergency plans.
Yodsel Wangchuk Rinzin