Mercury (Hg) is a global pollutant, which is distributed worldwide due to atmospheric long-range transport. Via dry and wet atmospheric deposition, Hg enters aquatic ecosystems, where it could be transformed to highly toxic methylmercury (MeHg) by microorganisms. MeHg can be bioaccumulated and biomagnified through food chain to higher concentrations in some fish that could be hazardous to human health through consumption. To ease this global Hg pollution issue, international collaboration is required to clarify the mechanisoms of emissions, long-range transport, physical and chemical transformation, deposition, source-receptor relationships. The effectiveness of the Minamata Convention can be evaluated besed based on the collected information and data, and strategy can be adjusted accordingly, to protect human health and the environment from the hazards of Hg and its compounds. Although East, Southeast and South Asia are major emission source regions of Hg to the atmosphere, the ultra-trace level sampling and analytical techniques required for quantifying atmospheric Hg concentrations and fluxes are lacking in many countries, making Southeast and South Asia a blank area of atmospheric Hg monitoring. Therefore, this project is aimed to ameliorate this situation with following objectives: (1) assisting Taiwan EPA to handle atmospheric Hg related international collaborative activities; (2) continuing operation of the Center for Environmental Monitoring and Technology; (3) continuing operation of the atmospheric Hg monitoring education and training platform of the Asia-Pacific region; providing consultation and training in environmental monitoring techniques; assisting APMMN partner countries in environmental monitoring capacity enhancement. Based on the existing foundation in bilateral environmental protection collaboration, we assisted the Environmental Protection Administration of Taiwan to work with US Environmental Protection Agency (USEPA) and National Atmospheric Deposition Program (NADP) on the following tasks: making Center for Environmental Monitoring and Technology the regional technical center; continuing operation of the APMMN and expanding regional atmospheric Hg monitoring activities; assisting regional countries in Hg analysis of atmospheric samples and strengthening the QA/QC procedures; providing personnel training and assisting regional countries in capacity building in ultra-trace level Hg sampling and analysis to enhance monitoring capacity; promoting multilateral cooperation in atmospheric Hg monitoring, and information exchange and data sharing; studying the distribution characteristics, variation, and influence of regional atmospheric Hg. Major results of this project include: (1) Online discussion of annual APMMN activities and developing plan with Taiwan EPA, USEPA and NADP; (2) Extension of Taiwan-Japan mercury wet deposition sampler inter-comparison study for another year to May 2023; (3) Organized and hosted “the 11th Annual Asia-Pacific Mercury Monitoring Network Partners Meeting Virtual Workshop”; (4) Attended the “UNEP Strengthening mercury research capacity in developing countries for science-based policy making virtual meeting”; (5) Completed the NADP review report; (6) Attended “the 2022 NADP Spring meeting MELD Workshop”; (7) Assisted the payment of the 2022 and 2023 AMNet annual fees and the signing of the cooperative agreement; (8) Attended ICMGP 2022 “Introduction to New Methods for Measuring Reactive, Particulate, and Gaseous Oxidized Mercury Chemistry and Concentrations Workshop”; (9) Participated the UNEP ROAP mercury laboratory proficiency testing – Asia and the Pacific. Lab performance is satisfactory; (10) Participated the Environment and Climate Change Canada project “Passive air sampling for mercury on a global scale”; (11) Conducted the PET bottle test; (12) Maintenance and update of the APMMN website; (13) Hg analyses of 264 wet deposition sampler inter-comparison samples; (14) Hg analyses of 282 samples from APMMN partners, including 210 wet deposition samples and 72 quality assurance samples; (15) Submitted the proposal for the application strategy of passive air samplers for Hg; (16) Completed the sampling and analysis of 36 passive air samples for Hg; (17) Collection and compilation of the Asia-Pacific region and worldwide atmospheric mercury monitoring information. Studying the characteristics and variation in atmospheric mercury distribution in the Asia-Pacific region; (18) Collection and compilation of worldwide mercury wet deposition information; (19) Assessment of the impact of Asia-Pacific mercury outflow on Taiwan; (20) Collection and compilation of new mercury monitoring techniques; (21) Assisted partner countries in the operation and maintenance of wet Hg deposition sampling stations; (22) Assisted the mercury wet deposition monitoring capacity building in Australia.

Atmospheric Mercury, Wet deposition, Passive air sampler