Inventory of U.S. 2012 dioxin emissions to atmosphere

Area of Science:

• Environmental Science
• Atmospheric Chemistry
• Pollution Control

Background:

• The U.S. Environmental Protection Agency (EPA) previously published dioxin emission inventories for 1987-2000.
• Dioxins, including polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), are persistent organic pollutants with significant environmental and health concerns.

Purpose of the Study:

• To provide an updated inventory of U.S. atmospheric dioxin emissions for the year 2012.
• To analyze trends in dioxin emissions from controlled industrial and open burning sources.
• To quantify dioxin emissions from U.S. waste-to-energy (WTE) power plants.

Main Methods:

• Compilation of dioxin emission data for controlled industrial and open burning sources in the U.S. for 2012.
• Separation of emission sources into two primary classes: controlled industrial and open burning.
• Detailed data collection from major U.S. waste-to-energy companies for emission calculations.

Main Results:

• Controlled industrial dioxin emissions decreased by 95.5% from 14.0 kg TEQ in 1987 to 0.6 kg in 2012.
• Open burning source emissions increased from 2.3 kg TEQ in 1987 to 2.9 kg in 2012.
• U.S. waste-to-energy plants emitted 3.4 g TEQ in 2012, representing a small fraction of total controlled and open burning emissions.

Conclusions:

• Significant progress has been made in reducing dioxin emissions from controlled industrial sources.
• Open burning remains a notable source of dioxin emissions, showing an increasing trend.
• Waste-to-energy plants are a minor contributor to overall U.S. dioxin emissions, indicating effective emission control technologies.