Mercury

he transport of PCBs in soil
• PCBs continuously enter into soil in different ways.
• Precipitaion of particulate matters is the main resource of
PCBs in soil, while they are also partly from the sludge manure,
leakage from the landfill and the prepartion of pesticides, etc.
It is reported that the content of PCBs in the soil are in
most cases over 10 times higher than that in the air above.
• Except temperature, some other environmental factors such as
clay content and the level of choloridization of PCBs also have
some effect on the volatilization of PCBs in the soil.
Biodegradation and invertible absorption contribute little to
the depletion of PCBs.
• Only the process of volatilization is most likely to cause the
depletion of PCBs, especially those having more Cl content.