Bhopal, India, methyl isocyanate

During the night of December 2-3,1984, the worst industrial disaster in history occurred at Union Carbide s plant in Bhopal, Madhya Pradesh, India. Methyl isocyanate (MIC) liquid, an intermediate used in making Sevin, Union Carbide s name for the pesticide carbaryl, came into contact with water, boiled violently, and turned into MIC gas. Unchecked by various safety systems, tons of highly toxic MIC gas escaped from storage tank E610. A cloud of MIC gas descended upon shantytowns just outside the plant, as well as on Bhopal city. Estimates of the death toll from exposure to the gas, immediately or in the first 2 weeks, range from 2000 to 8000 or more. If those who died months or years later from MIC exposure are counted, the death toll rises to between 20,000 and 30,000. More than 500,000 people suffered injuries from exposure to the gas and its effects on the environment. ... 

There are three types of TAP emissions continuous, intermittent, and accidental. Both routine emissions associated with a batch process or a continuous process that is operated only occasionally can be intermittent sources. A dramatic example of an accidental emission was the release of methyl isocyanate [624-83-9] in Bhopal, India. As a result of this accident, the U.S. Congress created Tide III, a free-standing statute included in the Superfund Amendments and Reauthorization Act (SARA) of 1986. Title III provides a mechanism by which the pubHc can be informed of the existence, quantities, and releases of toxic substances, and requires the states to develop plans to respond to accidental releases of these substances. Eurther, it requires anyone releasing specific toxic chemicals above a certain threshold amount to aimuaHy submit a toxic chemical release form to EPA. At present, there are 308 specific chemicals subject to Title III regulation (37). 

Naphthol is mainly used in the manufacture of the insecticide carbaryl (59), l-naphthyl A/-methyicarbamate/ iJ-2j5 - (Sevin) (22), which is produced by the reaction of 1-naphthol with methyl isocyanate. Methyl isocyanate is usually prepared by treating methylamine with phosgene. Methyl isocyanate is a very toxic Hquid, boiling at 38°C, and should not be stored for long periods of time (Bhopal accident, India). India has developed a process for the preparation of aryl esters of A/-alkyl carbamic acids. Thus l-naphthyl methylcarbamate is prepared by refluxing 1-naphthol with ethyl methylcarbamate and POCl in toluene (60). In 1992, carbaryl production totaled > 11.4 x 10 t(35). Rhc ne-Poulenc, at its Institute, W. Va., facihty is the only carbaryl producer in United States. 

The worst disaster in the history of the chemical industry occurred in Bhopal, in the state of Madhya Pradesh in central India, on December 3, 1984. A leak of methyl isocyanate (MIC) from a chemical plant, where it was used as an intermediate in the manufacture of the insecticide car-baryl, spread beyond the plant boundary and caused the death by poisoning of more than 2,000 people. The official figure was 2,153, but some unofficial estimates were much higher. In addition, about 200,000 people were injured. Most of the dead and injured were living in a shanty town that had grown up next to the plant. 

The study of the accidents in chemical facilities, during transportation, storage and others, the research of the chemical products, which are produced and stored, are important points in the preparation of the defence against chemical terrorism. An example of such an accident is the explosion at the Union Carbide pesticide manufacturing plant (Dec. 3, 1984), which scattered toxic methyl isocyanate (MIC) over the city of Bhopal, India. During the first few days up to 4000 people died of painful, harrowing deaths [10],... 

The 1984 methyl isocyanate release in Bhopal, India that resulted in 2000 fatalities... 

On December 4, 1984, approximately 40 metric tons of methyl isocyanate was accidentally released in Bhopal India. The incident resulted in an estimated 2000 deaths within a short period (Lees 1996 A5-1). 

Event 5 Toxic Chemical Leak—Methyl isocyanate (MIC). Union Carbide Corporation, Bhopal, India (December 3, 1984). 3,000-7,000 people killed immediately 20,000 cumulative deaths 200,000-500,000 injured post-traumatic stress continued medical consequences (Lees 1996). 

The worst chemical disaster in history occurred on December 3, 1984, in Bhopal, India, a city of some 1.6 million people in the state of Madhya Pradesh. On that date in the middle of the night, a tank at the Union Carbide India Ltd. plant leaked between 25 and 40 tons of methyl isocyanate, a volatile colorless liquid, into the atmosphere of Bhopal. This highly toxic gas settled onto the city and its inhabitants in a silent, if odorous, cloud. The results were horrific some 3800 people died and another 2700 experienced total or partial permanent disability. By some estimates, more than 10% of the population of Bhopal—170,000 people—suffered some adverse effect from the methyl isocyanate leak. 

On December 3, 1984, a toxic gas release from a pesticide plant in India killed nearly 3000 people and injured at least 100,000 others. The chemical that leaked was methyl isocyanate, a chemical intermediate that was supposed to be stored in a cooled bunker near the plant s outer boundary. The vapor is highly toxic and causes cellular asphyxiation and rapid death. Despite engineering and procedural provisions to prevent its release, a total system breakdown resulted in the release of 40 tons of the deadly material into the densely populated community of Bhopal. Because of this incident, the plant was dismantled and ultimately the parent corporation. Union Carbide, was forced to make a number of organizational changes. The occurrence is considered by many to have been the most tragic chemical accident in history. 

Methyl isocyanate is a very dangerous chemical. It was responsible for the deaths of over 2,500 people, perhaps as many as 10,000 people, in the worst industrial accident ever, that of the carbamate insecticide plant in Bhopal, India on December 3, 1984. It is a very toxic chemical. This tragedy is discussed in more detail in Chapter 25. Methyl isocyanate can be made from phosgene and methylamine, which would circumvent use of the isocyanate. Phosgene is made from chlorine and carbon monoxide, but it is also very toxic and dangerous. 

One of the most notorious cases of industrial disaster took place in 1984 in Bhopal, India. A plant with a license from the Union Carbide company was making methyl isocyanate (MIC), CH3NCO, which is an intermediate for the manufacture of pesticides. MIC boils at 39 °C, and the vapor density is heavier than air and very toxic by inhalation and skin absorption. The maximum allowable air concentration is 0.02 ppm by volume over 8 h. MIC also reacts with water and produces heat, which must be removed to prevent boiling over. On that day in 1984, the cooling system failed during... 

The other source of water pollution is toxic chemicals, of which the chemical and petroleum industries are a major source. The oil spiU from the Exxon Valdez in Alaska and the methyl isocyanate release from Bhopal, India, are the most widely known examples. Here the overall problem is that chemicals are released that are not normally found in nature, and consequently plants and animals have no defenses against them. 

Bhopal, the site of the largest chemical accident in the past 50 years, wasn t an explosion but rather an uncontrolled reaction. The plant in Bhopal, India, owned jointly by Union Carbide and the Indian government, was producing methyl isocyanate as an intermediate for a pesticide. Water was admitted into a storage tank containing this chemical, which caused it to hydrolyze and produce CO, HCN, and unreacted MIC, which spread downwind into a crowded slum nearby and caused many deaths and casualties. The desired reaction to synthesize MIC was... 

Draw two resonance structures for methyl isocyanate, CH3NCO, a toxic gas that was responsible for the deaths of at least 3000 people when it was accidentally released into the atmosphere in December 1984 in Bhopal, India. Assign formal charges to the atoms in each resonance structure. 

The tragedy at the Union Carbide plant in Bhopal, India in 1984 highlighted, among other issues, the critical need for careful monitoring of methyl isocyanate in the environment. 87 and 88 are both lumophore-spacer-secondary... 

Methyl isocyanate was the toxic agent involved in the most catastrophic industrial accident of all time, which took place in Bhopal, India, on December 2, 1984. This accident occurred when water got into a tank of methyl isocyanate, causing an exothermic reaction that built up pressure and ruptured a safety valve. This resulted in the release to the atmosphere of 30 to 40 tons of the compound over an approximately 3-h period. Subsequent exposure of people resulted in approximately 3,500 deaths and almost 100,000 injuries. 

One of the worst industrial accidents occurred in Bhopal, India, on December 2 and 3, 1984. It was due to the leakage of methyl isocyanate (MIC) released from the Union Carbide pesticide manufacturing plant. More than 3,000 people who resided in areas adjacent to the manufacturing plant died within a few hours after exposure to MIC. Death was attributed to severe pulmonary toxicity, followed by... 

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