Technical report 125

Case study 4: Persistent organic pollutants (POP)

This study is based on the release of a POP-type chemical predicted to undergo long-range transport from undefined emission sources. POPs can be present in gaseous form in the atmosphere or bound to the surface of solid particles. Contamination of remote areas such as the Arctic environment can be via atmospheric, oceanic current and/or freshwater transport. POPs can undergo several cycles of transport, deposition and re-volatilisation. These processes are often strongly influenced by temperature.

The chemical is assumed to have generic characteristics, i.e. low abiotic and biotic degradation / transformation rates, a high vapour pressure and high hydrophobicity (potential to bioaccumulate). This allows for bioaccumulation in fatty tissues of living organisms and slow metabolism, which confers the compound’s persistence and accumulation in food chains.

In the last 30 years international regulations (see Chapter 3) and voluntary phase-outs have significantly reduced exposure. Nevertheless new POP like substances are regularly developed which could cause new pressures on ecosystem services in Arctic regions (Vorkamp and Riget, 2014).