1 2 3 6 7 8-hexachlorodibenzo-p-dioxin July 8, 2019 16 32 64 128 1 2 3 6 7 8 hexachlorodibenzo p dioxin 2 3 7 8-tetrachlorodibenzo-p-dioxin health effects 2 3 7 8-tetrachlorodibenzo-p-dioxin 2 6-dichlorobenzoic acid