Quantum yields for the photodecomposition of polychlorinated dibenzo-p-dioxins (PCDDs) in water-acetonitrile solution

Photochemical degradation was an important process affecting the fate of certain contaminants on vegetation and in water. The quantum yields for the photodecomposition of several PCDD isomers under environmentally relevant conditions were determined. The compounds studied were 1,2,3,4,7-penta, 1,2,3,4,7,8-hexa-, 1,2,3,4,6,7,8-hepta-, and 1,2,3,4,7,8,9-octachlorodibenzo-p-dioxin in water and acetonitrile, with phototransformation carried out at 313 nm.