Because of their toxicity to non-target organisms and high persistence in the environment, their production and use were restricted and banned following the Stockholm Convention 2001 (United Nations 2001). Today, they are still found in multiple media all over the world . As lipophilic and semi-volatile compounds, they tend to adsorb to organic matter, but can be volatilized and thus be transported and deposited in areas far away from their points of production or application via LRAT. Therefore, they tend to accumulate in colder areas, e.g. Arctic/Antarctica or in high altitudes, where they reach concentrations comparable to source regions .