Basic concept of Bhopal Gas Tragedy: A Toxic Nightmare

Bhopal Gas Tragedy was a catastrophic industrial accident that occurred in Bhopal, India, on December 3, 1984. A leak of toxic methyl isocyanate gas from a Union Carbide plant resulted in the deaths of thousands of people and caused long-term health problems for many more. The incident is considered one of the worst industrial disasters in history.

1. BHOPAL GAS TRAGEDY

2. INTRODUCTION UCIL was a pesticide plant which manufactured the pesticide carbaryl (chemical name: 1-naphthyl methylcarbamate) under the brand name Sevin . Carbaryl was discovered by an American company Union Carbide Corporation (UCC) which was UCIL’s parent company holding a majority stake. Minority stakes were held by Indian banks and the public. UCIL manufactured carbaryl using methyl isocyanate (MIC) as an intermediate. Although there are other methods to produce the end-product, they cost more. MIC is a highly toxic chemical and extremely dangerous to human health. Around midnight of 2 nd December 1984, residents of Bhopal surrounding the pesticide plant began to feel the irritating effects of MIC and started fleeing from the city. However, thousands were dead by morning.

3. THE ACCIDENT During the night of 2-3 December 1984, water entered Tank E610 containing 42 tons of MIC. The resulting exothermic reaction increased the temperature inside the tank to over 200°C (392 °F) and raised the pressure. About 30 metric tons of methyl isocyanate (MIC) escaped from the tank into the atmosphere of Bhopal in 45 to 60 minutes.

4. FACTORS LEADING TO GAS LEAKING Storing MIC in large tanks and filling beyond recommended levels. Poor maintenance. Failure of several safety systems. Safety systems being switched off to save money-including the MIC tank refrigeration system which could have mitigated the disaster severity. Plant location close to a densely populated area. Undersized safety devices. The dependence on manual operations. In the early 1980s, the demand for pesticides had fallen, but production continued, leading to buildup of stores of unused MIC. (Sharif et al., 2020)

5. HOW METHYL ISOCYANATE LEAKAGE HAPPENED? Union Carbide India's Bhopal facility housed three 68,000-litre liquid MIC storage tanks: E610, E611,E619. The MIC tank was pressurized with inert nitrogen gas. The pressurization allowed liquid to be pumped out of each tank. One of the tanks E610 lost the ability to contain nitrogen gas. As per the rules, each of the tank could not be filled more than 30 tons of liquid MIC.But this tank had 42 tons. An attempt to re-establish pressure in tank E610 on 1 December failed, so the 42 tons of liquid MIC contained within still could not be pumped out of it According to reports, by December 2 eve water had entered malfunctioning tank, which resulted in runaway chemical reaction. The pressure in the tank increased five times by night. By midnight, the workers in the MIC area started feeling the effects of MIC gas. The decision to address the leak was to made a couple of minutes later. However by then the chemical reaction in the tank had reached a critical state. About 30 tons of MIC escaped from the tank into the atmosphere within an hour. (Banerjee et al., 2021)

6. EFFECTS The cloud contained a mixture of substances. The gases were heavier than air, displacing oxygen. The initial effects of exposure were coughing, vomiting, severe eye irritation, respiratory issues and a feeling of suffocation. More than 150,000 people still suffer from disorders caused by the accident and the subsequent contamination – respiratory diseases, kidney and liver disorders, cancers and gynecological issues. No one knows exactly how many thousands of people died. The official certified death toll was 3,928 deaths. The Sambhavna clinic "estimates 8,000 deaths during the first weeks, and another 8,000 since then". The government of Madhya Pradesh confirmed a total of  3,787 deaths related to the gas release .   It is estimated 100,000 to 200,000 people have permanent injuries.Reported symptoms are: eye problems, respiratory difficulties, immune and neurological disorders, cardiac failure secondary to lung injury, female reproductive difficulties and birth defects among children born to affected women.

7. Bhopal gas disaster, a tragedy no compensation could settle………

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