They are very stable and fat-soluble, and therefore accumulate in the food chain. They may be present as contaminants or by-products in the manufacture of other halogenated compounds.

• 二恶英非常稳定,能够溶于脂肪,因此能够在食物链中积累。二恶英在其它卤代化合物的制造中能够成为污染物或副产品。