Mercury

The atmosphere is purified of PCBs through
rainwater flush and dry or wet precipitation, the
process of which transports the pollutants from
atmosphere to water or soil.
Hydrophobic organic matters in the atmosphere
are mainly in gaseous state or absorpt state. PCBs in
the gaseous state and PCBs absorpt by particulate
matters can reach the earth’s surface through dry or
wet precipitation such as gas phase absorption,
gravitational settling and eddy diffusion, etc.