Industrial accidents methyl isocyanate

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. 

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... 

On December 3 and 4, 1985, a chemical release causing a massive toxic gas cloud occurred at the Union Carbide India, Ltd, plant in Bhopal, India. (Union Carbide is now a part of The Dow Chemical Company.) The process involved used methyl isocyanate (MIC), an extremely toxic chemical, to make Sevin, a pesticide. According to various authoritative reports, about 1,700-2,700 (possibly more) people were killed, 50,000 people were affected seriously, and 1,000,000 people were affected in some way. The final settlement may involve billions of dollars. It was one of the worst industrial accidents in history. The accident occurred when about 120-240 gallons of water were allowed to contaminate an MIC storage tank. The MIC hydrolyzed, causing heat and pressure, which in turn caused the tank rupture disk to burst. 

The accident involving the generation of heat and the leakage of methyl isocyanate (MIC) that happened in Bhopal, India, from midnight of December 2 through Dec. 3, 1984, developed into the greatest industrial disaster in history. The death toll was reportedly 2,500, and it was said that more than 10,000 people suffered health-disorders as after-effects. Approximately 200,000 people in total were affected by the leaked gas. 

As discussed earlier, nuclear accidents liave not been die only accidents to occur in recent times. Other disasters at chemical plants have been responsible for a much greater loss of life. Tlie worst disaster in the recent history of the chemical industry occurred in Bhopal, in central India, on December 3, 1984. A leak of methyl isocyanate (MIC) from a chemical pkint, where it was used as an intermediate in the manufacture of a pesticide, spread into tlie adjacent city and caused the poisoning dcatli of more tlian 2500 people apja-oximately 20,000 others were injured. 

India, resulted in toxicity and death. The toxicological profile of methyl isocyanate was not known, and the chemical was released under uncontrolled conditions. Industrial accidents by definition are not specified conditions of exposure but must be borne in mind as a factor to consider. With increased knowledge of chemicals and the factors that affect these chemicals, the ability to assess and react to adverse conditions is enhanced. 

In 1982, the European Union s Council Directive 82/501/EEC on the major-accident hazards of certain industrial activities, also known as the Seveso Directive, was adopted. The Directive was mostly designed to promote information flow and created the requirement that each Member State (i.e., each country belonging to the European Union) appoint a Competent Authority to oversee safety issues. The Seveso Directive was amended twice, following major accidents at the Union Carbide chemical factory in Bhopal, India in 1984 (a leak of methyl isocyanate caused thousands of deaths), and at the Sandoz chemical warehouse in Basel, Switzerland in 1986 (fire-fighting water contaminated with mercury, organophosphate pesticides and other chemicals caused massive pollution of the Rhine River and the death of hundreds of thousands of fish). Both amendments, broadened the scope of the Directive, in particular to include the storage of dangerous substances. 

Although toxic releases, in general, are not the principal cause of major accidents (relative to fire and explosion) associated with the chemical industry, they are a just cause of "considerable public apprehension" [1327a]. This concern has been compounded by an event which occurred in Bhopal, India in December 1984, in which over 2500 people were killed by a single toxic release of methyl isocyanate. 

The chemical industry received a wake-up call for improved safety when 40 tons of methyl isocyanate escaped from a pesticide plant into a densely populated area of Bhopal, India on Dec. 3,1984. This resulted in 3500 deaths and 150,000 injuries.85 According to one reviewer86 the accident... 

India currently has a better record of environmental compliance, although one need only look at the covers of back issues of Chemical Engineering News to find pictures of polluted effluent from Indian manufacturers. The industrial accident followed by the airborne dispersal of methyl isocyanate at Bhopal was not so long ago and was perhaps the event that triggered the Indian industry to better manage its processes and effluent. 

Note An industrial accident during the manufacture of carbaryl in Bhopal. India on December 3, 1984 resulted in the leakage of an unknown amount of methyl isocyanate into the air. Over 2,000 people died and an estimated 200,000 were exposed to the vapor Chetn. A Eng. News 62, 6 (Dec. 10, 1984) ibitL 63, 14 (Feb. 11, 1983). Series of articles on follow -up studies on survivors Indian J. Exp. Biol 26, 149-176, 201 -204 (1988). 

Even under the best of circumstances in which all possible exposure modes are controlled, it would be foolhardy to make a conclusion of zero exposure. Numerous industrial chemical accidents have occurred. One particularly catastrophic incident occurred in Bhopal, India, in 1984 in which the extremely toxic gas methyl isocyanate leaked out of a closed and contained system resulting in the deaths of perhaps tens of thousands of people. The Bhopal incident dramatically demonstrates that zero exposure (and therefore zero risk) can never be concluded, but it is also possible to go too far in the direction of concluding that all toxic chemicals must be banned for all applications, which is sometimes referred to as the precautionary principle . This important nuance is discussed later in this chapter. 

Methyl isocyanate is used primarily in making pesticides and herbicides such as carbaryl and aldicarb. It is also used to a lesser extent to produce plastics and polyurethane foams. Methyl isocyanate was attributed to the deaths of more than 3000 people in Bhopal, India, in a very tragic industrial accident during the 1980s. 

The world s worst industrial disaster occurred in Bhopal, India, in 1984 in which nearly 40 metric tons of methyl isocyanate was released from a pesticide plant killing over 3000 people. Most deaths resulted from pulmonary edema within 3 days of accident. Many follow-up studies indicated pulmonary, ophthalmic, neurological, reproductive, immunologic and hematologic toxic effects among the survivors. 

The release of methyl isocyanate (MIC) from the Union Carbide chemical plant in Bhopal, India, in December 1984 has been called the worst industrial accident in history Conservative estimates point to 2,000 fatalities, 10,000 permanent disabilities (including blindness), and 200,000 injuries [38]. The Indian government blamed the accident on human error—the improper cleaning of a pipe at the plant. A relatively new worker was assigned to wash out some pipes and filters, which were clogged. MIC produces large amounts of heat when in contact with water, and the worker properly closed the valves to isolate the MIC tanks from the pipes and filters being washed. Nobody, however, inserted a required safety disk (called a slip blind) to back up the valves in case they leaked [12]. 

A host of worldwide major accidents (a chemical explosion in Texas City, Texas, in 1947 that killed 581 and injured about 3,500 the leak of methyl isocyanate gas in Bhopal, India, in 1984 and the explosion of the Piper Alpha oil platform in the North Sea in 1988 Table 21-1) focused industry and the public to the problem in the United States. This was further prompted by the vision... 

Methyl isocyanate, CHj—N=C=0, is used in the industrial synthesis of a type of pesticide and herbicide known as a carbamate. As a historical note, an industrial accident in Bhopal, India, in 1984 resulted in leakage of an unknown quantity of this chemical into the air. An estimated 200,000 people were exposed to its vapors, and over 2000 of these people died. 

There have been numerous unfortunate events that have lead to an increased awareness of the importance of safety when producing agricultural crop protection agents. The worst industrial accident in history occurred in Bhopal, India in 1984 at a plant producing the carbamate pesticide, cm baryl. Volatile methyl isocyanate gas that escaped from the plant in one night resulted in the immediate death of over 2,500 people (d). Current estimates of mortality resulting from that accident are between 15,000 and 20,000 (7). Many synthetic processes in chemical production can result in fire, explosions or other unforeseen events such as those recorded in Bhopal. 

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