Explainer

Soluble Dilemma

How long does it take to dissolve a human body?

Lye

Assassins for Mexican-American drug cartels have been dissolving their victims’ bodies in chemicals, according to a piece published Tuesday in the New York Times. The process is known colloquially as making pozole, in reference to a traditional Mexican stew. It can take several hours to make a pot of pozole. How long does it take to dissolve a human body?

About the same, with the right chemicals and equipment. The assassins typically use sodium hydroxide or potassium hydroxide, strong bases commonly known as lye. (The Times story misidentified their reagent of choice as an acid.) Heated to 300 degrees, a lye solution can turn a body into tan liquid with the consistency of mineral oil in just three hours. If your kettle isn’t pressurized, you won’t be able to heat the solution much above the boiling point of water, 212 degrees, and it might take an additional hour or two to complete the process. Narco-hit men did not pioneer this technique. Adolph Luetgert, known in his day as the “Sausage King of Chicago,” dumped his wife into a boiling vat of lye in 1897, then burned what was left. Police eventually found bone fragments in the factory’s furnace.

Nowadays, most bodies are liquefied for legitimate reasons. Some universities use industrial digesters to dispose of cadavers used for research and medical education. The machine, which looks like an enormous pressure cooker, mixes about 70 gallons of water with a small amount of lye. When the five- to eight-hour cycle is complete—that’s three hours to destroy the body, plus a few more to heat and cool the solution—the liquefied remains are safe to pour down the drain. A perforated basket catches the solids that survive the process, including implanted medical devices and “bone shadows”—calcium phosphate that makes up about 70 percent of the mass of bones and teeth. The bony bits can be crushed into a fine white powder.

Acids can dissolve a body more completely than lye—liquefying even the bones and teeth—but it takes longer and can be hazardous. British murderer John George Haigh used sulfuric acid to dissolve at least six of his victims in the 1940s. He processed the bodies in a 45-gallon oil drum and reported that the victims dissolved completely in about two days. He also said he had to leave the room, finding the fumes intolerable. (Sulfuric acid can cause third-degree burns. A sprinkling of lye will merely irritate the skin but can be more dangerous if it’s mixed with water.)  In 1980, a Gambino crime family henchman dissolved the body of a man who had accidentally killed John Gotti’s son in a traffic accident, using a 55-gallon drum and an unknown acid.

In addition to being safer and more efficient, lye is also easier to obtain than strong acids. You can purchase 8 pounds of it—enough to dissolve a few bodies—from soap-making or farm-supply stores for less than $15. If you can’t wait for delivery, pick up some drain cleaner from the supermarket, but it’s so dilute that you may need to use quite a few bottles. Sales of strong acids are much more tightly monitored, because they can be used in bomb-making (PDF).

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Explainer thanks Bradley D. Crain of BioSAFE Engineering Worldwide and Rebecca J. Wilson of the University of Tennessee.

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