Italian dioxin release
The Italian dioxin release refers to a significant environmental disaster that occurred on July 10, 1976, in Seveso, Italy, when a chemical factory explosion led to the release of harmful dioxins into the atmosphere. The explosion at the ICMESA factory resulted from an overheated chemical reaction and released a white plume that spread over a wide area, affecting around 5,000 residents. Following the incident, there were immediate reports of health issues, including nausea, skin irritation, and the development of chloracne among those exposed. The disaster also caused the death of thousands of animals and resulted in the evacuation of more than 700 people from the most affected zones.
In response to the contamination, authorities implemented strict measures, including the emergency slaughtering of livestock to prevent dioxin from entering the food chain. While scientific assessments on the link between dioxin and cancer in humans have been mixed, ongoing studies of the Seveso population have indicated a rise in certain cancer rates among residents exposed to the toxic chemical. The Seveso disaster has had a lasting impact on public health discussions and environmental regulations in Italy and beyond, highlighting the potential risks associated with industrial chemicals and their management.
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Italian dioxin release
THE EVENT: Explosion at a chemical factory in Seveso, Italy, that resulted in the release of dioxin
DATE: July 10, 1976
Exposure to the dioxin released in the chemical plant explosion killed thousands of small animals and adversely affected the health of some five thousand people, many of whom continued to experience the negative effects for years following the incident.
On July 10, 1976, a chemical-reaction chamber exploded at a factory in Seveso, Italy, about 21 kilometers (13 miles) north of Milan. The factory, owned by Industrie Chimiche Meda Societa Anonima (ICMESA), produced the phenoxy-type trichlorophenol 2,4,5-T. Developed in 1945, this herbicide was used to control broad-leaved weeds and brush along highways and railroads, in rangeland and forests, and in wheat, rice, corn, and sugarcane fields. Agent Orange, a that received widespread use during the Vietnam War, is made from a combination of trichlorophenol 2,4,5-T and 4,4-D. The U.S. Environmental Protection Agency (EPA) restricted use of 2,4,5-T to rice fields and rangeland in 1979 and banned the herbicide entirely in 1985. One of the chief complaints was that 2,4,5-T contains dioxin, minute quantities of which cause cancer in animals. The that settled over Seveso contained an estimated 1.8 kilograms (4 pounds) of dioxin.
The disaster occurred when the chemical mixture in a reactor became seriously overheated and exploded, releasing a white plume that shot into the atmosphere to a height of about 45 meters (150 feet). The plume turned into a cloud that drifted in a southerly direction before cooling and settling over an area of approximately 280 hectares (700 acres), exposing some five thousand people. Those living closest to the ICMESA factory experienced nausea and skin irritation on exposed parts of their bodies. People who had been outdoors during the explosion developed burnlike sores on their faces, arms, and legs. Widespread cases of chloracne, an acnelike symptom that results from industrial to dioxin, also occurred. All residents of the area developed headaches, dizziness, and diarrhea. Birds were especially vulnerable to the chemicals and died quickly, often before they could fly out of the area. Approximately 3,300 small animals such as rabbits, mice, chickens, and cats sickened and died soon after the accident.
Five days after the explosion, authorities instructed the not to eat fruits or vegetables from the most affected areas. Nineteen children were hospitalized and later evacuated. Two weeks after the disaster occurred, Milan’s health administration determined that dioxin contamination from the cloud was serious enough to warrant evacuation of the population. This began on July 26 with the relocation of more than seven hundred people living in Zone A, a 108-hectare (267-acre) area directly south of the ICMESA plant. People in the surrounding 269-hectare (665-acre) Zone B were allowed to remain in their homes, but the area was sealed off from nonresidents. Italian army troops strung barbed wire around Zone A and patrolled the perimeter. To prevent toxins from entering the food chain, authorities ordered the emergency slaughtering of farm animals, and by 1978 some 77,000 animals had been killed. Scientific evidence that dioxin causes cancer in humans has been mixed, but an ongoing study of Seveso residents found elevated of several cancers following the dioxin exposure.
Bibliography
Ballarin-Denti, A., et al., eds. Chemistry, Man, and Environment: The Seveso Accident Twenty Years On—Monitoring, Epidemiology, and Remediation. New York: Elsevier, 1999.
Consonni, Dario, et al. “Mortality in a Population Exposed to Dioxin After the Seveso, Italy, Accident in 1976: Twenty-five Years of Follow-Up.” American Journal of Epidemiology 167, no. 7 (2008): 847-858.
Gorski, Chris and Alla Katsnelson. "Facing Chemistry's Destructive Side." Chemical and Engineering News, vol. 101, no. 26, 11 Aug. 2020, cen.acs.org/environment/Facing-chemistry-destructive-side/101/i26. Accessed 18 July 2024.
Schecter, Arnold, and Thomas Gasiewicz, eds. Dioxins and Health. 2d ed. New York: Taylor & Francis, 2002.