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Paul Müller: DDT – Poison For the World

In 1939, Paul Müller, chemist in Basel, makes a ground-breaking discovery: DDT is soon hailed as a wonder-chemical for widespread use in agriculture and disease control. Today, it has become a symbol for environmental pollution that inadvertently triggered new, ecological ways of approaching the environment.

Strasbourg, 1874. Othmar Zeidler describes a chemical compound which, due to its simple structure, receives the not so simple name dichlorodiphenyltrichloroethane.

Fast-forward 60 years: A research team at Geigy in Basel is trying to synthetically produce a pesticide. One of the team’s members, the chemist Paul Müller, is experimenting with substances based on a market-leading moth poison.

Small dosis, great effect…

Four years and 350 substances later: In September 1939, Müller enters the formula for dichlorodiphenyltrichloroethane in his research calendar. Testing it on bluebottle flies, he notices that it takes effect in small doses and for an extended period of time.

1942: DDT is patented and launched on the market in two commercial pesticides. Within the next few years, DDT becomes one of the most widely used agricultural pesticides. It is also used to protect humans from insect-borne diseases like typhus and malaria.

1945: Complaints that the substance is no longer effective come from Switzerland and Sweden. Similar reports emerge in the US a few years later. It becomes clear that insects have developed a resistance against DDT.

Stockholm, 1948: Paul Müller is awarded the Nobel Prize in Physiology or Medicine “for his discovery of the high efficiency of DDT as a contact poison against several arthropods”.

…and even greater side-effects

1962: American biologist Rachel Carson publishes her groundbreaking book Silent Spring. Using the example of DDT, she exposes the disastrous consequences of the overuse of pesticides on nature and human health. DDT takes a very long time to break down, so it remains in the nutritional chain, leading to long-term deposits in the tissue of birds and mammals. A severe decline in bird of prey populations, for example, is traced back to the thinning of eggshells due to DDT.

May 2001: At the start of the new millennium, 122 countries sign the Stockholm Convention that bans the agricultural use of DDT worldwide. Today, DDT is still permitted in small quantities for disease control, mainly malaria control, with India and Ethiopia as the largest users. Its use remains controversial.


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