In the last 3 years several farms raising cattle, river buffalo and sheep have been unable to sell dairy milk due to the presence of high levels of dioxins. Furthermore, several cases of abortion (around 25% of total births) and abnormal foetuses (2.5% of total births) were recorded in two flocks of sheep raised in the province of Naples where a higher level of dioxins (5.27 pg/g fat, as human WHO TCDD equivalent) have been found in the milk mass than that permitted (3.0 pg/g fat, as human WHO TCDD equivalent).
Dioxins belong to a large family of halogenated aromatic hydrocarbons widespread in the environment and known to be mutagenic. Dioxins do not occur naturally but are produced when manufacturing some herbicides (i.e. 2,4,5-T), germicides (i.e. hexachlorophene), pulp and paper, as well as during the combustion of wood in the presence of chlorine, by fires involving chlorinated benzenes and biphenyls and by municipal waste incinerators. Some possible sources of dioxins, like paper bleaching, seem to be noticeably reduced or eliminated by new bleaching technologies (Jorling, 2000). The best-known dioxin contaminant is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), which has various toxic effects on both the liver and immune system with evident teratogenic effects in both humans (Manz et al., 1991; McGregor et al., 1998; Bertazzi et al., 2001; Rier and Foster, 2002; Pesatori et al., 2003) and mice (Chapman and Schiller, 1985; Kociba, 1991).
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