title: Occurrence and source of chlorinated polycyclic aromatic hydrocarbons (Cl-PAHs) in tidal flats of the Ariake Bay, Japan.
abstract: In this study, we hypothesize that natural photochemical reactions of polycyclic aromatic hydrocarbons (PAHs) in tidal flats are responsible for the occurrence of chlorinated polycyclic aromatic hydrocarbons (Cl-PAHs). This study aims to survey the impact of photochemical reactions using a combination of field surveys and lab-scale experiments. Concentrations and profiles of PAHs and Cl-PAHs in road dust and sediments collected from seven tunnels and two watersheds, respectively, were determined. In the lab-scale experiments, anthracene was irradiated with ultraviolet (UV) light under various salinity conditions. No detectable Cl-PAHs were found in the road dust. However, Cl-PAHs were detected in the sediments from 700 to 6.1 × 10(3) pg g(-1) and specifically from downstream sites. 2-Monochloroanthracene (2-Cl-ANT) and 9,10-dichloroanthracene (9,10-di-Cl-ANT) were dominant in the sediments. In the Domen River watershed, the ∑Cl-PAHs and the salinity showed a significant positive correlation (p < 0.01) in the sediments, while such a correlation was not found for PAHs. 2-Cl-ANT, 9-monochloroanthracene, and 9,10-di-Cl-ANT were identified as transformation products in the UV irradiation experiments. Production of these Cl-PAHs was dependent on the solution salinity. These results support our hypothesis, and we conclude that photochemical reactions significantly contribute to the occurrence of Cl-PAHs in the studied tidal flats.
authors: Graduate School of Environmental and Symbiotic Sciences, Prefectural University of Kumamoto, 3-1-100, Tsukide, Higashi-Ku, Kumamoto, Japan, 862-8502.
authors: Kenshi
authors: K
authors: Sankoda
authors: Tomonori
authors: T
authors: Kuribayashi
authors: Kei
authors: K
authors: Nomiyama
authors: Ryota
authors: R
authors: Shinohara
mesh_terms: D061006:Bays; D004391:Dust / Q000032:analysis; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000032:analysis; D006843:Hydrocarbons, Chlorinated / Q000032:analysis* / Q000737:chemistry; D007564:Japan; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis* / Q000737:chemistry / Q000528:radiation effects; D054712:Salinity; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry / Q000528:radiation effects
chemical_list: D004391:Dust; D006843:Hydrocarbons, Chlorinated; D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical