M. Jang et Sr. Mcdow, BENZ[A]ANTHRACENE PHOTODEGRADATION IN THE PRESENCE OF KNOWN ORGANIC-CONSTITUENTS OF ATMOSPHERIC AEROSOLS, Environmental science & technology, 29(10), 1995, pp. 2654-2660
Benz[a]anthracene photodegradation rates in toluene solutions containi
ng co-solutes were compared using a photochemical turntable reactor. E
ach cosolute investigated was found at relatively high concentrations
in atmospheric particulate matter. Benz[a]anthracene photodegradation
was accelerated by the presence of 9,10-anthraquinone, xanthone, 2-fur
aldehyde, 2,4-dimethylbenzaldehyde, 9,10-phenanthrenequinone, 2-acetyl
furan, and furfuryl alcohol. Decay was inhibited by 7-benzanthrone. Ot
her compounds had little or no effect on benz[a]anthracene decay. Poss
ible photochemical reaction mechanisms are discussed, and it is conclu
ded that several competing mechanisms may be responsible, including el
ectronic energy transfer followed by reaction from the triplet state,
singlet oxygen attack, and radical chain reactions initiated by hydrog
en abstraction of aerosol constituents. The results suggest that parti
cle organic composition can strongly influence polycyclic aromatic hyd
rocarbon photodegradation rates in atmospheric aerosols.