Bhopal Gas Poisoning – India – December 3, 1984

Union Carbide’s factory was built to provide insecticide for India’s farmers so they would not lose crops. When demand for insecticide dropped Union Carbide began to cut costs wherever it could and, in the process, created circumstances that led to the disaster.

In the early hours of December 3, 1984, tons of poisonous gas escaped from Union Carbide’s factory at Bhopal, India. Methyl isocyanate, a highly toxic substance, was being processed here to produce insecticide for farmers. The nighttime gas leak caught people still in their beds. Eight thousand were killed and another quarter million injured, some very seriously. The problem began late on the evening of December 2 when water entered one of the big storage tanks containing methyl isocyanate at some stage of conversion. A chemical reaction was triggered and both temperature and pressure rose quickly. Officials at the plant knew what was happening and could also see that pressure was going to build up until something gave way but they were unsure about what to do.

A warning siren was available to warn local residents of any danger but workers were slow in turning it on. Shortly after midnight, the storage tank was breached and gas shot outward. Even then, no siren was sounded for an hour. By that time an area of more than fifteen square miles was contaminated and thousands were dying. Bhopal was a city of 800,000 people, mostly Moslems, which had tripled in size over the previous twelve years, largely due to the arrival of Union Carbide’s pesticide plant in 1969. The first ten years of the plant were highly successful and adequate safety precautions were in place.

Indian chemical engineers were taken to the United States for training and then brought back to their own country to oversee operations and train new staff. By the beginning of the 1980s it was a different story. Huge losses had overtaken the company, partly due to lack of demand for pesticides. The green revolution, the use of new and better grains for seed, was yielding a surplus of food and there was less need to buy expensive pesticides in order to reduce losses from insects.

As profits slumped, cost cutting measures appeared. Instead of sending their chemical engineers to the United States for training, men who had taken some university science were given a four-month crash course locally and then handed major responsibilities within the plant. These people were not qualified chemical engineers so they could be paid less, thus reducing the budget for staff. For people at this level of responsibility it was usually $30 a month. The level of training steadily deteriorated with each group of new workers. Additional workers were frequently needed because the best-trained chemical engineers often left for better pay and greater security elsewhere.

Men were hired to work in the very sensitive and highly toxic Methyl Isocyanate (MIC) Unit with limited training and little practical experience. This was the unit that had been a highly controversial addition to the plant. It was added in 1980 for the same reason that lay behind other decisions of that time—it was cheaper. Bhopal was the only Indian plant to use this chemical and the company’s U.S. plant in West Virginia was the only other one using it. In addition to the risks associated with MIC, instead of the safer yet more expensive chemicals used at all the other Indian plants there was the challenge of adding one more building to the Bhopal installation to store MIC.

Local government leaders knew that Union Carbide’s factory should never have been built where it was. It was too close to areas of concentrated settlement and, since it first opened, more and more people moved to places close to the plant. The local officials were faced with a big addition because Union Carbide decided it would save a lot of money if large quantities of MIC were stored at the site instead of frequent additions of small amounts being added from time to time.

The city administrator was insistent. He asked the company to set it up farther out, away from the populated areas in order to avoid tragedies like the one that hit Mexico City only a few weeks earlier and killed large numbers of workers whose homes were close to the plant. In the debate that ensued, the company won out and the city administrator lost his job. He said it was not due to the position he took over the MIC unit but others wondered if that was really true.

Symptoms of the victims who were exposed to the poisonous gas took different forms depending on distance from the factory. They included immediate irritation, chest pain, breathlessness, and if no help was at hand the problem developed into asthma, pneumonia, and finally cardiac arrest. Almost nothing was known by those affected as to what to do in a tragedy of this kind. Had they known, simple protective measures were possible. If, for example, a wet cloth is placed over nose and mouth until help arrives, many lives can be saved.

The accident shocked the world and Union Carbide, the United States parent company, was particularly concerned because it operated a facility of the same kind in West Virginia. Some months later on, in August of 1985, that same plant experienced a leak like the Bhopal one but fortunately safety measures were in place to prevent widespread damage. For the people of Bhopal, similar safety measures were almost nonexistent. The failure to anticipate the developing leak was only the beginning. An analysis conducted in January of 1985 revealed that safety measures were totally inadequate.

A refrigerator designed to prevent dangerous chemical reactions in storage tanks had been shut down, ostensibly as a cost-cutting move. Had this been in place the buildup of pressure and the resultant leak would never have happened. A mechanical vent scrubber to detoxify escaping gas with caustic soda was not working. A network of waterspouts for neutralizing toxic gas was also inoperative, and so was another safety installation, a high-flare tower that would burn off dangerous gases high in the air. These conditions together with evidence of unreliable instruments throughout the plant confirmed the investigators’ findings. Bhopal’s security was totally inadequate.

Bhopal had experienced as many as six smaller accidents in the previous three years, all of them related to gas leaks, most frequently chlorine, a part of the methyl isocyanate manufacturing process. This particular gas is best known because of its use as poison gas in World War I. Chlorine comes from simple salt. Once broken away from its partner sodium, chlorine becomes a heavier-than-air gas, and an unstable chemical. It will recombine easily with carbon, and with material in the bodies of living things. But the chemical combinations formed by chlorine are known to cause cancer and other diseases. A single accident at a chlorine plant has the potential to kill hundreds of thousands of people. The accident at Bhopal killed 8,000 and injured a quarter million more.

Fallout from the accident was felt across the chemical industry. Safety audits and new regulatory standards became a primary focus of government and industry. Nongovernmental agencies increased their public awareness campaigns to ensure there would never again be another Bhopal. Concerns about technology transfers, the relations between economic and environmental issues, and the interests of labor all led to intense debate over public policy. In India, The Disaster Management Institute was formed to provide long-term planning in order to prevent future industrial accidents. The chemical industry responded with the formation of The Center for Chemical Process Safety to develop management strategies for the industry.

Poisonous gas spilled from a Union Carbide plant at Institute, West Virginia, in August of 1985, sending 130 people to hospital. The cause of the accident was almost identical to the one that was caused by the same company on a much bigger scale in India. New equipment had just been installed to make the plant safer but something went wrong. The lessons from Bhopal had not yet been learned. The plant at Institute produced the pesticide Temik from MIC just like Union Carbide’s operation in India.

Before the Bhopal tragedy the company transported MIC to other plants across the United States. After Bhopal, public concern forced the company to convert MIC to a less toxic chemical, aldicarb, before shipping it to other locations. This concern was heightened when the cause of the accident was known. The very same thing that went wrong in India was repeated when a valve failed and aldicarb heated up, bursting the container and escaping outside.

Within twenty minutes of the accident Union Carbide notified local emergency services. Fifteen minutes later the gas reached the town of Institute. People were warned to stay indoors but many were caught outside. These suffered from irritations to eyes, nose, throat, and lungs. It appeared that aldicarb had broken down into more volatile irritants in the course of being heated up before it escaped. The runaway reaction was identical to what happened in India. Fortunately, in West Virginia, action to correct the problem was quick and effective.

Some concern remained after the accident, particularly since its cause had been directly related to the installation of a new warning system designed to prevent the kind of thing that happened at Bhopal. The new system, known as “Safer,” analyzed wind speed and weather conditions on a continuing basis in order to predict the movement of escaping gas in case of a leak. Unfortunately, once again, even at the headquarters of the chemical company’s operation, the new safer system failed to work.

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