Excerpt 103: A disaster that no one talks about...

Case: Bhopal gas tragedy

The Union Carbide plant was in the state of Madhya Pradesh in central India. The plant was partially owned by Union Carbide and partially owned locally. The nearest civilian inhabitants were 1.5 miles away when the plant was constructed. Because the plant was the dominant source of employment in the area, a shantytown eventually grew around the immediate area.

History:

The problem persisted in varying degrees until the Green Revolution, a popular term referring mainly to the tremendous increases in cereal grain production in certain underdeveloped areas, especially India, Pakistan, and the Philippines, in the late 1960s through the cultivation of hybrid strains and economic changes brought by new agricultural, rural practices in those countries. For a number of years now, India has been a food surplus country. The change from traditional farming to capitalist farming under the Green Revolution required pesticides, among other things.

Indian National Congress Party (Congress) was in power in MP, and Mr. Arjun Singh, currently the federal Minister for Human Resources and Development, was the Chief Minister of MP in 1984. Singh played a key role in having the agricultural office of Union Carbide India Limited (UCIL) move from Bombay to Bhopal in 1968.

Introduction:

The plant produced pesticides. An intermediate compound in this process is methyl isocyanate (MIC). MIC is a hazardous compound. It is reactive, toxic, volatile, and flammable. The maximum exposure concentration of MIC for workers over an 8-hour period is 0.02 ppm (parts per million). Individuals exposed to concentrations of MIC vapors above 21 ppm experience severe nose and throat irritation. Death at large concentrations of vapor is due to respiratory distress.

MIC demonstrates several dangerous physical properties. Its boiling point at atmospheric conditions is 39.1°C, with a vapor pressure of 348 mm Hg at 20°C. The vapor is about twice as heavy as air, ensuring that the vapors will stay close to the ground once released. MIC reacts exothermically with water. Although the reaction rate is slow, the temperature will increase with inadequate cooling and the MIC will boil. MIC storage tanks are typically refrigerated to prevent this problem.

Accident:

The unit using the MIC was not operating because of a local labor dispute. Somehow a storage tank containing a large amount of MIC became contaminated with water or some other substance. A chemical reaction heated the MIC to a temperature past its boiling point. The MIC vapors traveled through a pressure relief system and into a scrubber and flare system installed to consume the MIC in the event of a release.

Unfortunately, the scrubber and flare systems were not operating for various reasons. An estimated 25 tons of toxic MIC vapor was released. The toxic cloud spread to the adjacent town, killing over 2000 civilians and injuring an estimated 20,000 more. No plant workers were injured or killed. No plant equipment was damaged. The exact cause of the contamination of the MIC is not known.

If a problem with the process caused the accident, a well-executed safety review could have identified the problem. The scrubber and flare system should have been fully operational to prevent the release. Inventories of dangerous chemicals, particularly intermediates, should also have been minimized.

Aftermath:

The exact human death toll is still to be unknown; however, it is estimated that nearly 5,000 people died within 2 days, and the death toll eventually reached upward of 20,000. A total of 200,000 in a city of 800,000 (1984 population) were exposed to the gas. More than 60,000 of them required long-term treatment.

Many still are being born with disabilities, be it mental or physical. It has rendered the darkest spot in Indian history of industrialization.

The “settlement”:

In a settlement mediated by the Indian Supreme Court, UCC accepted moral responsibility and agreed to pay $470 million to the Indian government to be distributed to claimants as a full and final settlement. The figure was partly based on the disputed claim that only 3000 people died and 102,000 suffered permanent disabilities.

"The danger which is least expected soonest comes to us."

–?Voltaire, poet?

Reference