Pests

The Chemical Age Dawns in Agriculture

World War II was the first U.S. war in which diseases – many like typhus and malaria carried by insects – killed fewer people than bullets and bombs. The reason was DDT. The insect killer – or “insecticide” – had been discovered in 1939 and used extensively by the U.S. military during the war. So, it is no wonder that the postwar period saw the dawning of the chemical age in pesticides.

One of the sad facts of war is that more people usually die from disease than from direct hostile action. For instance, the Civil War was the most bloody war before WWII. From 1860 to 1865, almost 185,000 people died in battle, but an astounding 373,458 people died from disease, privation and accidents. From 1941 through 1945, 292,000 Americans died in battle and 115,000 died from other causes.

DDT was largely responsible for that decrease. Just before the war, a Swiss chemist named Paul Müller discovered that DDT (chemically, dichloro-diphenyl-trichloro-ethane) would kill insects. The U.S. and other governments jumped on that discovery because scientists knew that typhus was carried by fleas and malaria by mosquitoes. Hundreds of thousands U.S. soldiers were issued DDT powder and told to sprinkle it in their sleeping bags. Entire towns in Italy were dusted with DDT from the air to control lice. DDT was sprayed heavily on South Pacific islands to control mosquitoes. Word got back to the home front that this new miracle chemical was saving the lives of loved ones.

Farmers, in particular, took note and couldn’t wait to get their hands on the chemical. Diena Thieszen Schmidt remembers the futility of trying to contol bugs without insecticides. “We did everything we could think of,” she says. “We made noises at the end of the field. We smoked [set up smoke pots]. We tried everything to try to get rid of those army bugs.”

Between army ants, grasshoppers, corn borers and a horde of other bugs, farmers in the Midwest were fighting a never-ending battle against insects. On the West Coast, orchard growers had been using arsenic compounds like Paris Green to keep insects from destroying their crops, and they had gotten into trouble when arsenic residues showed up on apples and pears in the America, Britain and other countries. Agricultural groups had been fighting a running battle with muckrakers and reformers who wanted to place severe limits on the amount of pesticide residue that could be found on food.

DDT seemed to bypass that entire debate. Thousands of returning GIs could demonstrate that the powder didn’t seem to hurt human health. It was cheap and amazingly persistent and effective.

DDT also showed chemists the way to develop other insecticides and herbicides. The chemical was formulated by taking simple carbon-based molecules, like methane, stripping out one or more hydrogen atoms and replacing them with other compounds. Very quickly, chemists were developing new classes of chemicals to killed insects and weeds.

One of the first and most important was the weed killer – or “herbicide” – known as 2,4-D. It was developed in 1944.

So, as the war ended, a new chemical age began, and farmers were the main reason for the new age. By 1952, there were almost 10,000 separate new pesticide products registered with the USDA under a brand new law. Then, as today, agriculture uses 75 percent of all pesticides. Between 1947 and 1949, pesticide companies invested $3.8 billion into expanding their production facilities. They were rewarded by huge profits.

Many historians have called this the golden age of chemical pesticides – effective new chemicals were available and of all of the risks and dangers to human health and the environment were not yet known.

Written by Bill Ganzel, the Ganzel Group. A partial bibliography of sources is here.