Years ago, I assumed that denatured alcohol was alcohol that had undergone some useful chemical process that also made it undrinkable — when, in fact, denatured alcohol is perfectly drinkable alcohol that has been made undrinkable specifically to avoid the high taxes on spirits.
The moralistic attitude during Prohibition led the U.S. government to take this poisoning to another level:
The U.S. Treasury Department, charged with overseeing alcohol enforcement, estimated that by the mid-1920s, some 60 million gallons of industrial alcohol were stolen annually to supply the country’s drinkers. In response, in 1926, President Calvin Coolidge’s government decided to turn to chemistry as an enforcement tool. Some 70 denaturing formulas existed by the 1920s. Most simply added poisonous methyl alcohol into the mix. Others used bitter-tasting compounds that were less lethal, designed to make the alcohol taste so awful that it became undrinkable.To sell the stolen industrial alcohol, the liquor syndicates employed chemists to “renature” the products, returning them to a drinkable state. The bootleggers paid their chemists a lot more than the government did, and they excelled at their job. Stolen and redistilled alcohol became the primary source of liquor in the country. So federal officials ordered manufacturers to make their products far more deadly.
By mid-1927, the new denaturing formulas included some notable poisons — kerosene and brucine (a plant alkaloid closely related to strychnine), gasoline, benzene, cadmium, iodine, zinc, mercury salts, nicotine, ether, formaldehyde, chloroform, camphor, carbolic acid, quinine, and acetone. The Treasury Department also demanded more methyl alcohol be added — up to 10 percent of total product. It was the last that proved most deadly.
By the time Prohibition ended in 1933, the federal poisoning program had killed an estimated 10,000 people.