The facts about dioxins

The facts about dioxins

Dioxins are a family of chemical compounds that are not manufactured; rather, they are produced and enter the environment from a variety of sources, including industrial processes such as treating wood with preservatives and bleaching pulp and paper, and through incomplete combustion of petroleum products, wood and garbage.

They are persistent in the environment, accumulate in the food chain and are toxic to all life forms. They are linked to several types of cancer in humans and animals, birth defects, liver damage and weakened immune systems.

Dioxins are measured in parts per trillion. One part per trillion is equal to one second every 320 centuries or one drop of detergent in a 10-mile-long string of railroad cars filled with detergent.

Sediment sampling in lower Budd Inlet last year revealed dioxin levels ranging from 0.1 ppt to

52.7 ppt. The dioxin limit set by state and federal agencies for disposing of marine sediments at a South Sound marine disposal site near Ketron and Anderson islands is 3.8 ppt.

Here are some other ways to place the Budd Inlet dioxin contamination in perspective:

- The death rate for juvenile trout exposed to .0445 ppt of dioxin for 28 days was 50 percent.

- The state standard for dioxin in groundwater is .006 ppt.

- The United States Environmental Protection Agency health criteria for food consumed by humans is .000014 ppt of dioxin.

- The state toxic cleanup standard for dioxin found in residential soil is 6.67 ppt.

Source: Washington state Department of Ecology