Get the lead out! Switzerland facing the dangers of leaded gasoline (1947-2000)

On August 30. 2021, the United Nations Environment Programme announced the official end of leaded petrol production following the decision of Algeria – the last consumer country – to stop its distribution. A century ago – in 1921 – the properties of tetraethyl lead in gasoline to reduce engine knocking were discovered in laboratories affiliated with General Motors. Three years later, American scientists alerted the authorities about the potential hazards of the use of tetraethyl lead.

Considering these warnings and thanks to the involvement of toxicologists, Switzerland banned benzine containing lead compounds in April 1925. However, from 1947 the use of lead continued to be allowed under certain conditions. In the 1960s and 70s, several Swiss studies such as reports from the Federal Commission on Air Hygiene (1968) and other surveys on blood lead levels of people living near highways (1970) presented worrying evidence on the increasing presence of lead in the bodies of humans, animals and in soil. In the 1970’s there was scientific consensus around the fact that the emissions of leaded gasoline are dangerous for the health of humans and causes harm to plants. From the 1980s leaded gasoline was gradually replaced by unleaded gasoline until its use was finally abolished on January 1, 2000 in Switzerland and in the European Union.

Despite the fact that the Federal Department of the Interior already expressed concerns about the dangers of leaded gasoline’s use in 1924, questions remain over why warnings over the use of this substance were ignored and how the international economic context influenced its continued use. What types of measures were chosen in Switzerland to address issues over its continued use and public health concerns? Based on sources produced by Swiss authorities and media, this contribution engages with a wider historiographical debate concerning the treatment of warnings by the authorities, the role of experts and the involvement of economic actors in the political regulation of air pollution.