Dioxins are formed during incomplete
combustion and whenever materials containing
chlorine (e.g. plastics) are burned. Emitted in the atmosphere,
dioxins tend to deposit on soil and water but, being waterinsoluble,
they do not contaminate ground water sources.
Most dioxins in plants come from air and dust or pesticides
and enter the food chain where they bio-accumulate due to
their ability to be stably bound to lipids.