The following post is related to the Center’s work on a Health Impact Assessment of a proposed biomass-powered energy facility in the Shenandoah Valley of Virginia. The facility was proposed as a potential remedy to the issue of nutrient concentration related to trends in livestock production. Each post in the series describes one particular aspect of interest from the Center’s analysis.
What are Dioxins/Furans
Dioxins/Furans refers to seventeen different individual substances that are a byproduct of the burning of organic materials. Forest fires, automobiles, and industrial practices are common sources of dioxins/furans in the environment but the biggest contributor is the uncontrolled burning of trash.
Preliminary research into the risk associated with dioxins/furans suggests that they are carcinogenic (associated with cancer). The magnitude of this relationship is not fully understood yet
How Are People Exposed to Dioxins/Furans
As far as can be told by current research, exposure to dioxins/furans through breathing in contaminated air is not a huge concern. Air concentrations even in industrial areas are usually low. The biggest risk is from eating contaminated food. Dioxins/Furans can accumulate in the body and will accumulate up the food chain. Livestock and fish that eat contaminated grass or water will absorb the dioxins/furans and pass them up to humans who eat them. Because of this and the modern food service system that results in people eating food that was grown/raised from potentially far away, exposure to dioxins/furans could come from distant sources, not necessarily from obvious community locations.
How the Facility Would Impact Dioxins/Furans
Because dioxins/furans are a category of substances rather than a single substance, modeling their distribution required too many resources for this project. The facility in Minnesota has an annual release of 3.64e-07 tons per year. That means 0.000000364 tons or 0.012 ounces of dioxins/furans released per year. At this rate, it would take over 80 years for the facility to release a single ounce of dioxins/furans. Most power plants do not last that long. It is also worth mentioning that this rate comes from a facility that is older and less advanced than one that would be built in the Valley.
The key question is, would this amount of dioxins/furans be enough to cause a significantly increased health risk. The EPA estimates that the safe level of exposure to dioxins/furans is 7e-10 mg/kg-day or 0.0000000007 mg for every kilogram of body weight per day. That isn’t very much, but the facility isn’t emitting very much either. Moreover, the risk of dioxins/furans isn’t so much from the air that you breathe but from the food that you eat, which could be coming from an area with even higher exposure to dioxins/furans.