Assessment of Persistent Organic Pollutants load to marine environment by MAPPE-Global model focusing on European regional seas

摘要

MAPPE-Global modeling tool belongs to the group of the global box models for environmental fate and transportof POPs. The estimated error level of MAPPE-Global is about a factor of two, which suggests that the model could be considered as a tool for a screening or initial evaluation of chemical risk for POPs at global scale. The verified MAPPE-Global is applied in practical assessments of chemical loads to the European regionalseas. The PCBs case study relates to a sum of 22 congeners and considers two emission scenarios: first - thecurrent status relative to the 2010 year; second – a future projection corresponding to the 2020 year. The totalamount of 22PCBs released to air equals to 101.03 t for year 2010 and to 50.2 t for year 2020, respectively. TheBaseline scenario for Lindane assumes, for the reference year 2005, 86.6 t atmospheric emissions only fromEuropean sources and omits the impact of the long range atmospheric transport. The second scenario forLindane aims to targeting the situation in the year 2020. This scenario (denoted as LRT) suggests no emissionsto atmosphere from any European origin due to the banning of this substance but admits that Europe is affectedby an unavoidable „import” of 5.4 t Lindane through trans-continental air transport.According to the MAPPE-Global model, the extended European area is exporting to the marine water 3.7 t of22PCBs in 2010 and 1.9 t in 2020, respectively. In both scenarios, the most affected seas are the Mediterranean Sea (ca.35%from the total) followed by Northern (ca. 21.5%) and Black sea (ca. 19%). It was estimated that the Europeanseas receive by atmospheric deposition about 7.9 t of 22PCBs in 2010 and ca. 4t in 2020. This is two timesmore when comparing to the entire riverine discharge of 22PCBs for these years.MAPPE-Global forecasts 10.1 t riverine sea load of Lindane under the Baseline scenario and 0.26t in the caseof LRT meaning 97% reduction compared to the baseline option. The highest discharges are observed for Atlantic Ocean –in Baseline scenario 2.2t (21.8% from the total) and for LRT 0.06t (23%); and Mediterranean Sea - Baseline 3.5t(34.7%) and LRT 0.04t (15.4%). For the gamma-HCH, likewise for the PCBs, it is found that the atmosphericdeposition over the European seas dominate the river input to the coastal zone. Under the Baseline scenario,the total air deposition (50.2t/y) is about 5 times higher than the riverine component of the sea load. Potentially the outcome of MAPPE-Global model could serve in the assessments of different policy optionsrelated to the EU Water Framework Directive (WFD) or Marine Strategy Framework Directive (MSFD) as well asto support the implementation of the European sea conventions as HELCOM (Baltic Sea), OSPAR (North-EastAtlantic), MEDPOL (Mediterranean Sea) and BSC (Black Sea).