In the early 1900s, American grocery shelves were full of food treated with chemicals that nobody had tested. Manufacturers used borax, salicylic acid and formaldehyde to stop milk and meat from spoiling and there was no federal law requiring them to show those additives were safe to eat.
Harvey Washington Wiley, the chief chemist of the US Department of Agriculture, believed some of them were harmful, and in 1902 Congress funded him to test that belief on human volunteers. He recruited a dozen young men, many of them government clerks, who agreed to take all their meals at a special table in the department's basement.
The food was good, which was part of the appeal, but it came with measured doses of whichever preservative was being studied, and the men were weighed, examined and monitored as the weeks went on. Reporters found the whole thing irresistible and nicknamed the volunteers the Poison Squad, turning a government experiment into a national talking point.
The formaldehyde tests were the most dramatic, since nearly every participant became sick after fairly small doses and Wiley halted that phase early. The findings fed directly into the fight for federal food rules, and in 1906 Congress passed the Pure Food and Drug Act, the law that eventually grew into today's Food and Drug Administration.
AND STILL TODAY IT'S NOT MUCH BETTER.