Dioxin is an unwanted by-product of incineration, uncontrolled burning and certain industrial processes.

The term "dioxin" refers to a large family of compounds that includes 17 compounds of particular interest because it is thought that these compounds have similar mechanisms of toxicity.

Nevertheless, the toxicities of dioxins vary greatly, with the least toxic compound estimated to be 10,000 less potent than the most toxic.

Dioxins occur as complex mixtures of these 17 family member compounds.

Through regulation and voluntary efforts releases of dioxin to the environment have been dramatically reduced.

These efforts have been so successful that uncontrolled burning--not industry--is now the dominant source of dioxin.

This web page was designed to offer information about dioxins: what they are, where they are produced, why they are of concern and where levels are heading.