title: Photochemical degradation of PAHs in estuarine surface water: effects of DOM, salinity, and suspended particulate matter.
abstract: The photodegradation of several polycyclic aromatic hydrocarbons (PAHs) including phenanthrene, benzo(a)pyrene, and benzo(e)pyrene was studied under different estuarine conditions to elucidate the effects of dissolved organic matter (DOM), salinity, and suspended particles on PAH photodegradation in the estuarine surface water. Besides the competitive light absorption effect, DOM can accelerate the photodegradation of small PAHs such as phenanthrene by enhancing the formation of reactive intermediates and inhibit the photodegradation of large PAHs such as benzo[a]pyrene (BaP) and benzo[e]pyrene (BeP) by binding the PAH molecules. High salinity would accelerate the photodegradation of PAHs; however, the magnitude and direction of the salt effect are complicated in the presence of DOM due to the "salting-out" effect on the binding of PAHs with DOM. Suspended particulate matter in the estuary provides an alternative solid-phase photodegradation pathway for PAHs, which proceeds faster than the aqueous phase. Particulates apparently exert different effects on the photodegradation of phenanthrene (Phe) and BaP as a result of the combined effects of light absorption, particulate organic matter, PAH surface sorption, and concentration dilution in the presence of suspended particulate matter.
authors.affiliation: State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing, 100875, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Shang
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.forename: Zhenyao
authors.initials: Z
authors.lastname: Shen
authors.forename: Xuze
authors.initials: X
authors.lastname: Xiao
authors.forename: Hainan
authors.initials: H
authors.lastname: Yang
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Aidong
authors.initials: A
authors.lastname: Ruan
mesh_terms: D063366:Estuaries; D052638:Particulate Matter / Q000737:chemistry*; D010782:Photolysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000737:chemistry*; D054712:Salinity; D013535:Suspensions; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D052638:Particulate Matter; D011084:Polycyclic Aromatic Hydrocarbons; D013535:Suspensions; D014874:Water Pollutants, Chemical; D014867:Water