Intercontinental transport of persistent organic pollutants: a review of key findings and recommendations of the task force on hemispheric transport of air pollutants and directions for future research

Abstract

The Task Force on Hemispheric Transport of Air Pollution (TF HTAP) was established under the Convention on Long–range Transboundary Air Pollution (CLRTAP) to improve scientific understanding of the intercontinental transport of air pollutants and to deliver policy–relevant information on this issue. The first comprehensive assessment of POP intercontinental transport made by the TF HTAP was compiled in 2010 and published in 2011. The HTAP assessment was made possible by the contributions of a large network of experts in various national and international organizations and is intended to support further development of international policy and regulation of POPs under the frameworks of the UN ECE CLRTAP and the Stockholm Convention on POPs. By summarizing the outcome of past studies on POPs, the assessment highlights the evidence of POP intercontinental transport and the associated threat to human health and the environment. It presents the current state of knowledge on levels of POPs in the environment, emission inventories and projections, modeling of long–range transport and fate in various compartments, interactions with climate change, as well as harmful effects on human health and ecosystems. Two important outcomes of the HTAP 2010 assessment are the summary of key scientific and policy–relevant findings, and the recommendations for further work which include the need to a more fully developed integrated approach to the pollution assessment. In its next phase, which extends to 2015, the Task Force is planning to cooperate across different thematic areas of scientific activity on intercontinental transport of pollution, and exploit synergies of effort in cases where particulate matter (PM), ozone, mercury, and POPs share common sources. It is recognized that a fully “integrated approach” for building a scientific understanding of POPs in the environment should encompass measurements, modeling results, and emission estimates, and in addition it should more explicitly include assessment of ecosystem effects.