Dibenzo-p-dioxin and its chlorinated relatives are chemically stable and accumulate in milk and throughout the food chain, creating significant health concern. A chlorinated relative of Dibenzo-p-dioxin, 2,3,7,8-tetrachloro-dibenzo-p-dioxin, was involved in a 1976 explosion in Seveso, Italy, creating widespread major health problems. Dibenzo-p-dioxins are generated as by-products in the manufacturing of herbicides, insecticides, fungicides, paper pulp bleaching, and in incineration. Sphingomonas sp. RW1 degrades dibenzo-p-dioxin through cleavage of the product of angular dioxygenation to catechol and 2-hydroxymuconate ([http://www.ncbi.nlm.nih.gov/pubmed/1575472|Wittich et al., 1992]). A similar pathway is known for diphenyl ether.