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In 1937 over 100 people died after ingesting "Elixir Sulfanilamide" manufactured by S.E. Massengill Company of Tennessee. The product was formulated in diethylene glycol, a highly toxic solvent that is now widely used as antifreeze. Under the laws extant at that time, prosecution of the manufacturer was possible only under the technicality that the product had been called an "elixir", which literally implied a solution in ethanol. In response to this episode, the U.S. Congress passed the Federal Food, Drug, and Cosmetic Act of 1938, which for the first time required pre-market demonstration of safety before a drug could be sold, and explicitly prohibited false therapeutic claims.

Diethylene glycol is mainly used today as what liquid?
antifreeze