Seveso is a municipality located 20 km north of Milan. Until 1976 Industrie Chimiche Meda Società Azionaria (ICMESA) was located at the border with the town of Desio. ICMESA was a chemical industry of the Swiss company Givaudan (from 1963 belonging to the multinational pharmaceutical company Hoffmann-La Roche). ICMESA has since 1971 manufactured 2,4,5-trichlorophenol, a toxic substance used in herbicides and for the preparation of hexachlorophene (cosmetics).
Since the start of the production (late 40s) ICMESA caused a number of environmental problems in the surrounding area, especially pollution of watercourses and livestock deaths, never seriously contested by local institutions.
On 10th of July 1976, temperature and pressure in a reactor suddenly increased causing the opening of the safety valve and the diffusion in the atmosphere of a reddish cloud, which soon began to settle on a very populated area. It was attributed to human error.
Since July 14th effects of the explosion on the population, animals and vegetation were visible. The mayor of Seveso issued the day after an order in which it was forbidden to manipulate and eat vegetables grown near the factory. ICMESA's workers refused to continue working. The company, after a week revealed the name of the toxic substance: 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), highly toxic, carcinogenic and teratogenic.
Hundreds have been affected by a form of skin rash: lacloracne. On the 21st of July, the director and the deputy director of ICMESA were arrested for "culpable disaster" and a judicial process started. On July 24th, the mayor of Seveso ordered 179 people to leave their homes to be hosted in a residence. Subsequently, the same thing happened to many other people, even in other towns.
The affected area was divided into three areas (A, B and R) according to the level of pollution. Zone A (the most affected), already evacuated and extended for about 15 hectares, was also militarized.
On 7 August 1976, the Minister of Health, Dal Falco, and the Minister of Justice, Bonifacio, with the consent of the Prime Minister Andreotti, authorized therapeutic abortions for women in the area.
The approximation and the slowness of the remediation interventions has caused irritation in the evacuated population that, initially disorganized, then gathered in the "national coordination committee", on several occasions attempted to return to their homes.
On 11th of October 1976 a group of displaced people occupied the area A and blocked the highway Milano-Meda, asking to restart the reclamation process. So the politicians began talking about an incinerator to remove the contaminated material. Against this project, in December the highway Milano-Meda was again blocked. The movement forced policy to reclaim by isolating the contaminated material.
In June 1977, the Regional Council approved the remediation program. In October, the first evacuated families returned to their homes, although some had been demolished. The reclamation was limited to the area A and took more than 10 years. The land, the animals slaughtered and also the machinery used for the reclamation finished in two large containment tanks. Above these two tanks, the Natural Park "Bosco delle Querce” was then created.
In a criminal trial Givaudan offered 103.634.000.000 of Italian Lira to local authorities and to 25 plaintiffs, in return for their annulment and promises to continue later reimbursements to private entities. In 1983 the agreement was accepted and the Committee 5D (Difesa Diritti Danneggiati Dalla Diossina - Defence Rights Damaged From Dioxin) was created in order to defend the rights of citizens affected, including the cost of reimbursements.
On 23 May 1986, the Criminal Appeal issued the definitive judgment against ICMESA, mitigated by the transaction made by Givaudan with the plaintiffs. However, Givaudan's promises to continue the compensation was dismissed, except in rare cases of unfavorable civil convictions.
In April 2005 a civil trial against ICMESA was started before the Monza Court for moral damages caused to 1.132 people, all part of the committee 5D and the residents in areas B and A. The trial was lost both at first instance (2006), and in the Court of Appeal (2010).
In 2013 the Supreme Civil Court of Rome dismissed the appeal made by 326 people of the initial 1132, now forced again to pay court costs (approximately EUR 20,000).
The long-term health damage (the sharp increase in tumors is known) have never been quantified, so there has never been a compensation for the population.
At the time of the incident, there were serious shortcomings in the areas of legislative and professional safety and in the information for the citizens on the risks for environment and health. The new European legislation on chemical industrial equipment was launched in 1982 with the Council Directive 82/501 / EEC, called Seveso Directive. A central part of the Directive (later replaced by others) is constituted by the obligation to public information and fair safety measures.
In the aftermath of the disaster, at the end of August 1976, the Region asked the City of Seveso to express an opinion on the position in the municipal area of an incineration plant that would occupy an area of 36,000 m². The City Council, with one abstention, determined to place the plant in an area located north of the cemetery.
This decision was challenged by the population to such a point that the City Council of Seveso, in November, decided to repeal its decision of 29th August, and asked the Lombardy Region and the Province of Milan to suspend the contract for the construction of the incinerator and to accept the proposal of reclamation of the Committee of Civic Coordination. The latter suggested the method of the controlled waste to solve the problem with the placement of the polluted material in concrete caissons, pools, seismic and totally or partially embedded in the ground, covered with earth and greenery. According to the proposal of the Committee, the caissons were to be placed on the ground of ICMESA.