This Is The World's Smelliest Chemical

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Ever heard of thioacetone? If you live in Freiburg, Germany, you probably have. It takes a lot for people to forget a stink that once evacuated an entire city.

A factory in Freiberg attempted to make thioacetone in 1889. Thioacetone is not easy to make — the compound (CH3)2CS stays liquid only at temperatures of under -20 degrees celsius; get it any warmer and it clumps together and converts to a white solid called trithioacentone — but in either form, it stinks horribly. The odor from the factory was able to be smelled (what’s the word for smellable? Odible?) from half a kilometer away. It spread throughout the entire city, where it caused “fainting, vomiting, and a panic evacuation” according to factory workers.

That should have been enough for science, but it seems that chemists make it a point to never learn. In 1967, workers at an Esso station near Oxford decided to give it another go. A bottle came unstoppered and the entire lab found themselves “with an odour problem beyond our worst expectations.” The chemists replaced the stopper but, the incident, “resulted in an immediate complaint of nausea and sickness from colleagues working in a building two hundred yards away.” What’s more, it seems that thioacetone is the kind of smell that clings. Two chemists making tiny amounts of the thioacetone discovered that they couldn’t go to restaurants anymore because they stank so badly that waitresses sprayed the air around them with deodorant.


The Esso people abandoned the project, for obvious reasons, but not before they figured out how bad thioacetone stank. They were the ones to figure out that thioacetone’s odor had a reach of half a kilometer, but also that it only took a single drop to contaminate the area with its noxious smell. Thanks, guys!

Image: PishT.