Local and regional PM10 sources in an industrial city of Argentina

ANABELLA MORALES DEL MASTRO; PATRICIA SMICHOWSKI; LAURA DAWIDOWSKI; CRISTINA ROSSLER; PAGANI MARCIA; DARÍO GÓMEZ; MARCELO PEREYRA

Québec, Montreal

Congreso; International Union of Geodesy and Geophysics; 2019

CANADIAN GEOPHYSICAL UNION (CGU) / UNION GÉOPHYSIQUE CANADIENNE (UGC)

Under the frequent events of high PM10 concentrations above the air quality standard in the City of Bahía Blanca, Argentina, environmental officials and scientist co-designed a study to identify and estimate the contribution of local and regional aerosol sources. A combined analysis of the 2004-2011 time series of (i) surface observations (meteorological and PM10), (ii) satellite observations (MODIS near real time images, MODIS AOD and Ångström exponent and OMI ultraviolet aerosol index), and (iii) HYSPLIT air mass back trajectories, allowed distinguishing the contribution of the main regional sources. Each year, regional aerosol events were in the range 18-98. Of these events, the attribution was 72% re-suspended dust > 16% volcanic ash > 12% smoke mostly arising from biomass burning. Local source contributions were assessed using the PMF model with ad-hoc determined PM10-chemical profiles of potential sources (stack tests of the most relevant industrial sources, soils) and 111 air quality samples collected in two sites. Concentrations of chemical elements (Al, Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sb, Ti, V, Zn) were determined by ICP OES and ICP-MS and ions (Cl-, SO42-, NO3-, Na+, K+), by HPLC. Different source types were identified as the largest contributors in each site; industrial facilities and re-suspended soil exhibited the largest apportionment in one site while a thermal power plant was by the far the contributor in the second site. All in all, it was found that the regional sources are mainly responsible for the violations of the air quality standard.