Abstract
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in sediments (coastal, river, pond) and sediment core from Matsuyama, Japan, were analyzed to evaluate the distribution and historical trend of these compounds. PCDD/Fs concentrations in coastal sediments were relatively higher than river and pond sediments. The PCDD/Fs in atmosphere were mainly originated from combustion process and moved to soil by dry and wet deposition. The PCDD/Fs in soils were then entered into aquatic environment through run off. PCDD/Fs in paddy soil that contaminated from impurities of 2, 4, 6-Trichlorophenyl 4-nitrophenylether (CNP) and Pentachlorophenol (PCP) also flowed out to the sea through the rivers. Then PCDD/ Fs in river and seawater deposited to the bottom sediment.
PCDD/Fs contamination was clearly observed during 1960s-1980s, and ther environmental PCDD/Fs levels have been reduced in recent years.
Accumulation flux and deposition velocity to bottom sediment were calculated based on the data of the Matsuyama. The analytical data show that most of PCDD/Fs in water was bound to particles.
