Bhopal

Bhopal, the City of Lakes, is the capital of Madhya Pradesh and more or less plunk in the middle of India. It is home to about 2 million people, so about 3x bigger than Dublin and 2/3 the size of Kiev.  But for anyone over the age of 45, it is a metonym for Disaster. If you are older than that, you were a sentient being when, on the morning of 3rd December 1984, 2250 citizens of Bhopal woke up dead.  The cause was a toxic chemical leak from a factory in the city, that was owned by the multinational Union Carbide Corporation UCC.  The company was taking phosgene (which we've met before as a WWI weapon of mass-destruction) adding monomethylamine to make the intermediate methylcarbamoyl chloride MCC to produce methyl isocyanate MIC; in pictures:

MIC is a key precursor for making an insecticide called carbamyl, 1-naphthyl methylcarbamate, which UCC marketed as Sevin. Carbamyl is a neurotoxin and  is very widely used to kill malaria mosquitos and crop pests. It must be useful because, the production process is fraught with danger: phosgene for starters, but monomethylamine is a flammable gas and MIC is no slouch when it comes to killing people. So you wouldn't want to site an MIC factory in downtown Danbury, Connecticut where Union Carbide has its corporate headquarters. But if you're going to locate the factory in the Third World because of lower labour costs or slacker regulatory red-tape, you'd surely want to keep an eye on the plant's safety record. If you kill or disable too many workers, you will eventually run out of workers and bad press has a way of adversely affecting share-prices, which probably has more bite. But the safety record, albeit with 20/20 hindsight, is pretty shocking: there were leaks of phosgene in 1981 and 1982, three leaks of MIC in 1982, there were further leaks of MIC and phosgene and a cocktail of other toxic chemicals in 1983 and 1984.  These were noted by the Indian authorities and UCC was asked to clean up its act but UCC were major employers in the town and could shrug that sort of pressure off - if they chose to do so.

On the night of 2-3 December 1984, water was allowed to leak into a 40 ton vat of liquid MIC, the reaction with water generates heat which speeds up any chemical reaction. The heat and chemical by-products, including gaseous CO₂ increased the pressure in the storage cylinder until it blew a safety valve and voided more or less the entire contents of the vat into the atmosphere where is spread silently and insidiously across the sleeping town.  It is still talked about as the worst industrial accident . . . ever.  Half a million people were affected and 8,000 people died blistered and choking over the following two weeks, and an equal number have since had their lives fore-shortened. Of the 500,000 who were immersed in the cloud, at least 40,000 suffered continuing disablement. Because MIC is heavier than air, it hugs the ground like Sarin, and so short people (aka children) breathe in more of the toxic vapour than adults.  Those too poor to escape in a car, because they didn't own one, had to breathe deeper as they ran away and so succumbed in greater numbers.

The litigation and law-suits and counter-suits led to an out-of-court settlement of $450 million from Union Carbide for the victims of disaster. That took 5 years of legal wrangling and political posturing, and the lawyers on both sides made a lot of money. The CEO of the parent company Warren Anderson was charged with culpable homicide by the authorities in Madhya Pradesh but he hadn't been extradited in the thirty years since the leak occurred, he died a couple of months ago anyway. Nevertheless, in 2010 seven elderly Indian former employees of the Indian subsidiary UCIL were charged with negligent homicide fined and sentenced to 2 years in prison, although they were released almost immediately. I don't think we'll ever know how the water entered the tank and precipitated the catastrophic leak.  The management of UCC continues to cite sabotage by a disgruntled employee, everyone else seems to lean towards some measure of culpable negligence and ignoring fail-safes.  But it seems pretty clear that nobody was able to deal effectively with the leak as it progressed over several hours because of a combination of lack of imagination, lack of adequate or appropriate safety equipment, lack of training and lack of alarm systems. And cardinal sin among scientists and engineers: the log books were tamped with! A sorry state which doesn't give us much confidence that such a disaster could never happen again, not least because people didn't 'fess up to what they did and when.