Scorched tree leaves, dead animals and a toxic cloud escaping from a factory. Just half a century ago, the Italian town of Seveso unwillingly became the symbol of industrial disasters. On July 10, 1976, an explosion in the Icmesa chemical factory, in the neighboring town of Meda, released a large quantity of dioxin, a very toxic pollutant which quickly contaminated the surrounding area.
Despite the emergency, the situation is then minimized. The company did not notify the authorities until the next day and spoke of a simple “herbicide leak” likely to cause some damage to the crops. Residents are only asked not to eat local fruits and vegetables. The factory even reopened its doors the following Monday.
However, the situation is deteriorating day by day. Some residents, particularly children, develop severe skin disorders. Some go to the hospital. Doctors, who are still unaware of exposure to dioxin, are struggling to understand the origin of these symptoms. At the same time, rabbits, poultry and other small animals die suddenly, while the vegetation turns yellow and dries up.
It will take almost two weeks before the authorities recognize the seriousness of the situation and inform the population. Several neighborhoods were then evacuated, the consumption of agricultural products was prohibited, 2,000 hectares were declared contaminated and nearly 80,000 livestock were slaughtered.
European awareness
Despite these measures, those responsible continue to put the risks into perspective. The general director of Icmesa, Guy Waldvogel, affirmed at the time on Antenne 2 that “the product we manufactured was not terribly toxic. » He only acknowledges the presence of potentially dangerous impurities, ensuring that they were monitored. A version contradicted by many experts. At the time, journalist Hervé Duthu recalled that trichlorophenol had a composition close to that of defoliants used during the Vietnam War.
Moreover, the health situation is worrying to the point that, in an Italy where voluntary termination of pregnancy is not yet legal, therapeutic abortions are exceptionally authorized for certain women at high risk. Authorities also recommend that couples postpone their plans to have children. Studies carried out in the following years will highlight an increase in several cancers, notably of the liver, pancreas, bladder and digestive system, although a direct causal link cannot be established with certainty.
This disaster caused a sudden awakening and led to a turning point in the management of industrial risks in Europe. On June 24, 1982, the European Economic Community (EEC, the ancestor of the EU) adopted a first directive requiring Member States to identify, control and secure the most dangerous industrial sites.
Fifty years later, this regulation which aims to avoid another major accident still bears the name of this small Italian town, which has become the symbol of industrial disasters despite itself. In France, the Ministry of Ecological Transition identified 1,299 Seveso sites in 2025.
