ABSTRACT
Organic carbon and global temperature differences have been established as key drivers of Dioxins/Furans global distribution. Evidence indicates that most Dioxins/Furans are volatile enough to evaporate and deposit, among air, water, and soil at ordinary environmental temperatures. The processes such as sedimentation, adsorption, and volatilization are responsible for the distribution of Dioxins/Furans in the environment. Various studies at informal e-waste recycling sites (EWRSs) in Asian developing countries found the soil contamination levels of Dioxin/Furans from tens to ten thousand picogram tetrachlorodibenzo-p-dioxin (TCDD)-equivalents (TEQ) per gram. Vertical movement of Dioxins in soil may result from the saturation of sorption sites of the soil matrix, migration of organic solvents, or human or animal activity. Direct inputs of Dioxins/Furans to land typically lead to local contamination in relatively small areas. Unidentified sources have also been reported of Dioxins contamination in soil and sediment samples from different regions and of different ages.
