Chenxi Zhang, Xiaomin Sun* and Mei Li* Pages 1041 - 1049 ( 9 )
Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) are toxic, mutagenic and carcinogenic, causing great concern in the public. This review analyzes the properties, toxic effects and sources of PCDD/Fs. The distribution in various environmental compartments, including air, water, soil and sediments, are described. Further, the transformation of PCDD/Fs in the environment was emphatically discussed. The result shows that the fate of PCDD/Fs is mainly controlled by their gasparticle distribution behavior. For gas-phase PCDD/Fs, they are primarily depleted by photolysis and reactions with atmospheric oxidants. For particle-phase PCDD/Fs, dry and wet deposition are the effective removal mode. In the water body, the PCDD/Fs will be inclined to deposit in the sediment. Biodegradation may be a possible environment fate for the PCDD/Fs in sediments. Moreover, PCDD/Fs can enter into the atmosphere in the form of volatilization, especially in the summer. In the soil, the PCDD/Fs can be degraded through anaerobic dechlorination and aerobic dioxygenation, as well as by gas exchange across the air-soil interface. It has a strong net volatilized from the soil into the air for the PCDD/Fs with six or fewer chlorine atoms, while the hepta- and octachloroisomers are approached to the main air-soil exchange balance.
PCDD/Fs, sources, concentrations, dry and wet deposition, photolysis, oxidation degradation, biodegradation.
Department of Resourse and Environment, Binzhou University, Binzhou 256600, Environment Research Institute, Shandong University, Jinan 250100, Institute of Mass Spectrometer and Atmospheric Environment, Jinan University, Guangzhou 510632