Jamaica Ginger extract, known in the United States by the slang name "Jake," was a late 19th-century patent medicine that provided a convenient way to bypass Prohibition laws, since it contained between 70% and 80% ethanol by weight.
"Jake" was not itself dangerous, but the U.S. Treasury Department, which administered the Prohibition laws, recognized its potential as an illicit alcohol source, and because of this, it required changes in the solids content of Jake to discourage drinking. The minimum requirement of ginger solids per cubic centimeter of alcohol resulted in a fluid that was extremely bitter and difficult to drink. Occasionally, Department of Agriculture inspectors would test shipments of Jake by boiling the solution and weighing the remaining solid residue. In an effort to trick regulators, bootleggers replaced the ginger solids with a small amount of ginger and either castor oil or molasses.
A pair of amateur chemists and bootleggers, Harry Gross and Max Reisman, worked to develop an alternative adulterant that would pass the tests, but still be somewhat palatable. They sought advice from a professor at MIT who did not realize it was meant for internal consumption. They settled on a plasticizer, tri-o-tolyl phosphate (also known as tri-ortho cresyl phosphate, TOCP, or Tricresyl phosphate), that was able to pass the Treasury Department's tests but preserved Jake's drinkability. TOCP was originally thought to be non-toxic; however, it was later determined to be a neurotoxin that causes axonal damage to the nerve cells in the nervous system of human beings, especially those located in the spinal cord. The resulting type of paralysis is now referred to as organophosphate-induced delayed neuropathy, or OPIDN.
In 1930, large numbers of Jake users began to lose the use of their hands and feet. Some victims could walk, but they had no control over the muscles which would normally have enabled them to point their toes upward. Therefore, they would raise their feet high with the toes flopping downward, which would touch the pavement first followed by their heels. The toe first, heel second pattern made a distinctive “tap-click, tap-click" sound as they walked. This very peculiar gait became known as the jake walk and those afflicted were said to have jake leg, jake foot, or jake paralysis. Additionally, the calves of the legs would soften and hang down and the muscles between the thumbs and fingers would atrophy.
Within a few months, the TOCP-adulterated Jake was identified as the cause of the paralysis, and the contaminated Jake was recovered. But by that time, it was too late for many victims. Some did recover full, or partial, use of their limbs. But for most, the loss was permanent. The total number of victims was never accurately determined, but is frequently quoted as between 30,000 and 50,000. Many victims were immigrants to the United States, and most were poor, with little political or social influence. The victims received very little assistance, aside from being the subject of a few blues songs recorded in the early 1930s (e.g. "Jake Walk Papa" by Asa Martin, "Jake Leg Blues" by the Mississippi Sheiks, "Alcohol and Jake Blues" by Tommy Johnson and "Jake Liquor Blues" by Ishman Bracey).
Although this incident became well known, later cases of organophosphate poisoning occurred in Germany, Spain, Italy, and, on a large scale, in Morocco in 1959, where cooking oil adulterated with jet engine lubricant from an American airbase led to paralysis in approximately 10,000 victims, and caused an international incident.