1 2 3 7 8 July 8, 2019 16 32 64 128 1 2 3 7 8 9 1 2 3 7 8 pecdd 1 2 3 7 8 pentachlorodibenzo p dioxin 1 2 3 7 8 penta cdd 1 2 3 7 8-pdf 1 2 3 7 8 9 hxcdd 1 2 3 7 8 9-hcf 1 2 3 7 8-pentacles 1 2 3 7 8 9 hexahydropyren 1 2 3 7 8-pcdd 1 2 3 7 8-tcdd 1 2 7 3 8 in fraction 1 2 3 6 7 8 1 2 3 5 7 8 1 2 3 4 7 8 sequence