The deadline for Seveso III directive is approaching (1st June, 2015) and as some EcoMole people are experts in chemical legislature, it became a common topic of our talks recently. I have actually started to write a tool simplifying compliance with this regulation and so I looked up some historical data, which I would like to share with you.
Seveso (Google maps) is an Italian town (aprox. 23 000 inhabitants) located a few kilometers north of Milan, which became famous in 1976. But I am sure that its inhabitants would preferred to remain in anonymity.
On Saturday, 10th July, 1976, shortly after noon, a reactor exploded in Icmesa factory and released approximately 400 kg of reaction mixture to the atmosphere. The major components of released mixture were trichlorophenol and caustic soda, but a minor one brought most attention. The reactor released 14 kg of a dioxin - 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). It has been recognized as a potent carcinogen in experimental animals and it is classified as human carcinogen by WHO IARC - International Agency for Research on Cancer. There are some dissenting views on the human classification, but I will discuss them in some future article.
The released cloud of chemicals caused substantial damage to livestock, but fortunately, the accident did not cause any direct lost of human life and acute human health effect were not severe, mostly restricted to development of chloracne in 187 children and youngsters. While checking informations in this post I ran accross an article Environmental pollution and acne: Chloracne. Dermatoendocrinol. 2009, 1(3), 125â€“128 where you can find a lot of relevant data.
North Italy is densely populated, and so exposure of a large amount of people to elevated levels of TDCC led to many studies, some of them long term. A perfunctory search of Web of Science provides hundreds of scientific articles dealing with different aspects of this accident, especially about health effects of dioxine exposure.
But the most dramatic effect of the accident was felt in European chemical legislative process and resulted in a series of regulations:
I will return to Seveso in future posts, both as a chemist and as an information specialist. However even my preliminary studies already brought some facts I was not aware of: