|Abstract Title:||A Field Inter-comparison of Three Passive Air Samplers for the Monitoring of Gaseous Mercury in Ambient Air|
|Presenter Name:||Antonella Tassone|
|Company/Institution:||CNR-Institute of Atmospheric Pollution Research|
|Session:||Special Session - Metrological Traceability for mercury analysis and speciation|
|Co-Authors:||Antonella Tassone,Attilio Tassone,Maria Martino,Nicola Pirrone,Michelle Nerentorp Mastromonaco,John Munthe,Ingvar Wangberg,Geoff Stupple,Carl Mitchell,Adam Martin,Alexandra Steffen,Diana Babi,Erik Prestbo,Francesca Sprovieri,Sacha Moretti,Frank Wania|
Abstract Information :
The need to fill the gap in the knowledge of mercury (Hg) levels at different locations worldwide has long been leading the scientific community towards the development of new strategies that permit simple and accurate mapping of Hg concentrations, particularly in the atmospheric compartment, which is the main pathway of distribution in the environment. Accumulate experience over the years, and over the globe, points to the use of passive samplers (PASs) for Hg monitoring, which are advantageous due to their ease of use, affordability, and most importantly, the possibility to deploy them at poorly accessible sites. This study presents the outcomes of a field-based inter-comparison of three PASs, carried out at two sites in southern Italy and southern Ontario, from February to April 2019. The devices are the CNR-PAS with gold nanoparticles as a sorbent, developed by the Italian National Research Council, the IVL-PAS using an activated carbon-coated disk, developed by the Swedish Environmental Research Institute, and the MerPAS? using a sulfur-impregnated activated carbon sorbent, developed at the University of Toronto and commercialized by Tekran. All the samplers were deployed in triplicate with the addition of blank samples for multiple time periods, ranging from two to twelve weeks and the analytical results of gaseous Hg concentrations were compared in terms of detection limit, precision, as well as accuracy and bias, through comparison with gaseous elemental mercury concentrations recorded by Tekran 2537 analyzers at both locations. In Italy, all Hg concentrations from the PASs did not differ significantly from the average of the active sampling results, whereas differences among PASs were observed in Canada as a consequence of the harsher and more variable weather conditions. At both sites, the MerPAS? performed the best, as a lower detection limit, and higher precision and accuracy were obtained, especially for 8- and 12-week deployments.