Long-Range and Regional Atmospheric Transport of POPs and Implications for Global Cycling

One of the critical properties that define persistent organic pollutants (POPs) is a tendency toward wide-scale distribution in the environment. Atmospheric transport is one of the mechanisms through which this distribution occurs. Due to long-range atmospheric transport, POPs have been found in some of the most remote regions on Earth, including the Arctic, the Antarctic, and in high mountains. The latitudinal and long-term distribution of POPs on a global scale is controlled by a combination of thermodynamic temperature-driven processes, kinetically controlled advective phase-transfer reactions, and the degradation or transformation of POPs in environmental media. In addition to these processes, local and regional meteorology can greatly affect the distribution of POPs in mountains. From both a scientific and regulatory standpoint, it is often important to determine the geographic and emission sources of POPs. A number of approaches for identifying the sources of POPs in remote ecosystems are described herein.