Methyl isocyanate humans

The toxicity of methyl isocyanate comes as a surprise if its high sensitivity to hydrolysis is considered. But actually, it may reach its site of action in the human body largely undecomposed. This is due to the reversible addition of another nucleophile to this heterocumulene. The tripeptide gluthathione, which is supposed to protect the body against oxidizing agents, adds to the C=N double bond of the isocyanate by means of its thiol group whereby the thio-carbamate is formed. When the latter decomposes in a reversal to its formation reaction, it releases the intact toxic methyl isocyanate. 

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]. 

We have no way to anticipate unexpected events such as the attack on the World Trade Center and the impact this event had on surveillance technology and the visibility of IMS. This occurred because IMS provided a unique solution (or at least a more practical solution than the alternatives) and happened to be with the right degree of maturity to meet the technical requirements. An environmental accident that could lead to a human catastrophe, such as the release of methyl-isocyanate in Bophal, India, in 1984, may create a demand that can be met by IMS for on-site, real-time monitoring of a toxic compound. The existence of a large variety of IMS-based devices with the capability to handle many different types of samples and to provide results within seconds, with a high sensitivity and specificity in complex matrices for a suite of compounds, can be viewed as a solution looking for (more) problems. When such a need will arise, it is hoped the IMS community of researchers and manufacturers will be in a position to provide a practical, competitive solution. 

The Bhopal disaster, in terms of loss of life and human injury, is the most serious disaster in the history of the chemical and process industries. It took the form of a runaway polymerization of a highly toxic substance — methyl isocyanate (MIC). This took place not in a reactor, but in a storage tank. 

Usha Yes, you are right, Racheli. Bhopal was the worst chemical disaster ever. It occurred on the night of December 2,1984, in the Indian state Madhya Pradesh in the Union Carbide India Ltd (UCIL) plant that produced the pesticide Sevin from methyl isocyanate (MIC). MIC is extremely toxic to living organisms, causing in humans anything from severe coughing to death by suffocation. 

Ferguson JS, Schaper M, Stock ME, Weyel DA, Alarie Y (1986) Sensory and pulmonary irritation with exposure to methyl isocyanate. Toxicol Appl Pharmacol 82(2) 329-335 Fiamma MN, Samara Z, Baconnier P, Similowski T, Straus C (2007) Respiratory inductive plethysmography to assess respiratory variability and complexity in humans. Respir Physiol Neurobiol 156(2) 234-239... 

We may all say accidents happen. However, their occurrence may not only take human lives, destroy millions of dollars in property and lost business, they may also cost us our jobs and reputations. The Bhopal, India, accident in 1984 released methyl isocyanate and caused over 2500 fatalities. A petroleum refinery blew up in Houston, Texas, in 1989, killing 23 workers and damaging properly totaling U.S. 750 million, spewing debris from the explosion over an area of 9 km. Many thought that after the Three Mile Island nuclear accident in the United States in 1979 and the Chernobyl nuclear power plant disaster in Ukraine in 1986, we would finally get a handle on how to prevent accidents. Unfortunately, the Fukushima nuclear accident in 2011 proved otherwise (see Picture 2.1). 

Important Point Methyl isocyanate is an organic chemical that is used in the production of pesticides. Methyl isocyanate, commonly referred to as MIC, is extremely toxic to humans. Short-term exposure may cause death or adverse health effects, including pulmonary edema (respiratory inflammation), bronchitis, bronchial pneumonia, and reproductive effects. 

Decomposes when heated above melting point, 536°F/280°C, producing toxic fumes of arsenic, lead. Lead arsenates may be subject to redox reactions. Both arsenic and lead are known human carcinogens. PLUMBOUS ACETATE (6080-56-4) Pb(CjH302)2 3H,0 Contact with acids forms acetic acid. Incompatible with oxidizers, bases, acetic acid alkalis, alkylene oxides, ammonia, amines, bromates, carbonates, citrates, chlorides, chloral hydrate cresols, epichlorohydrin, hydrozoic acid, isocyanates, methyl isocyanoacetate, phenols, phosphates, salicylic acid sodium salicylate, sodium peroxyborate, potassium bromate resorcinol, salicylic acid, strong oxidizers, sulfates, sulfites, tannin, tartrates, tinctures trinitrobenzoic acid, urea nitrate. On small fires, use dry chemical, Halon, or CO2 extinguishers. 

S)-2-Isocyanato-3-phenylpropanoate (phenylalanine methyl ester isocyanate) has been used as a building block for 1,2,4-triazine azapeptides [304], which are inhibitors of thermolysin [309] and human leukocyte elastase (HIE) [310]. 

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