How Wisconsin Led the Fight to Ban DDT

The discovery of Dichlorodiphenyltrichloroethane (DDT) led to its wide use as a pesticide in the 1940s and 50s. This successful scientific advancement, however, came with unintended consequences.

DDT was created in the 1940s as a modern synthetic pesticide. At first it proved to be effective in both military and civilian populations to treat malaria, typhus, and other insect-borne human illnesses. It was also successful in controlling insects in agriculture and animal production, as well as in institutions, houses, and gardens. In Wisconsin, the pesticide was sprayed on trees in the city of Milwaukee to combat Dutch elm disease. Due to its affordability and effectiveness, there was widespread use of DDT in the United States. Over 2 million pounds of the pesticide were produced every month by the mid-1940s.

But the long-term effects of DDT were not yet fully understood and for years negative environmental impacts were overlooked. The chemical appeared to be such a promising product that the chemist who discovered DDT was awarded a Nobel Prize in medicine. It wasn’t until years later that several environmentalists and scientists began to call out the toxicological effects of broad DDT usage in the country. People who were concerned by the chemical’s effects discovered that because it remained in the environment for a long time, DDT was able to accumulate in the fat cells of animals and humans. Surprisingly, Wisconsin became a focal point of the DDT issue as more individuals advocated for its ban.

In 1968, one of Wisconsin’s most influential conservation organizations, the Citizens Natural Resources Association (CNRA) requested a ruling from the Department of Natural Resources on whether DDT constituted a water contaminant. The organization was able to submit this request to the state government thanks to a clause in Wisconsin law that allows any organized group of citizens to request that a state agency rule judgment on legal issues.

Legislative hearings related to DDT occurred from December 1968 to April 1969 and allowed the environmental organization to present its case. Not only did these hearings set an incredible environmental precedent in Wisconsin, but also in the entire country. The Wisconsin DDT hearings were covered in newspapers throughout the nation.

Arguments against DDT were delivered logically and persuasively. For example, DDT had been linked to the decline of numerous bird species, according to wildlife biologists. Predators at the top of the food chain accumulate lethal amounts of DDT in their bodies when they prey on fish and other animals that have the chemical in their systems. According to scientists at the time, bird species like eagles and falcons were most likely to suffer the deadly effects of DDT contamination.

To further support their claims, professors from the University of Wisconsin were invited by the CNRA to explain how DDT accumulates in the environment and affects the food chain. Additionally, it was argued that the chemical was capable of wiping out bird populations, since DDT caused bird eggs to develop a thin shell. The CNRA made remarkable arguments that were extremely difficult to refute.

Hearings were held until the middle of January, when they were suspended to give DDT's manufacturers time to draft a statement. When the hearing was reopened in April, it became obvious that the chemical manufactures had not conducted adequate research to prove that DDT was safe for the environment. As a result, DDT was ruled to be a water pollutant.

The Citizens Natural Resources Association pushed hard and were able to link DDT to concerns about Wisconsin’s environment. Using the legal process, the group and its allies were able to bring DDT concerns to public’s attention. States around the country quickly began to take action in prohibiting the use of DDT. This marked a huge win and a milestone for the environmental movement in the United States. CNRA, and the people involved banning DDT remained engaged in environmental activism for years to come.

[Sources: Wisconsin History Highlights ; Wisconsin DNR; Milwaukee Journal Sentinel ]

Wow such interesting article! I never knew that DDT could have such negative impacts. – Sandy Flores , Madison West High School (2021-09-28 15:25)
Very good work, Alan. Your writing is excellent and you provide lots of information. I look forward to seeing your articles. – Shoko Miyagi , UW-Madison (2021-10-14 11:42)