Assessment of fine and sub-micrometer aerosols at an urban environment of Argentina

MARIANA ACHAD; MARÍA LAURA LOPEZ; SERGIO CEPPI; GUSTAVO GERARDO PALANCAR; GERMÁN TIRAO; BEATRIZ MARGARITA TOSELLI

ATMOSPHERIC ENVIRONMENT

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2014 vol. 92 p. 522 - 532

1352-2310

In this work, PM2.5 sampling was conducted for the period April 2010 to December 2011 at an urban site of Córdoba City. The collected samples were individually analyzed for elemental composition by energy-dispersive Synchrotron Radiation X-Ray Fluorescence spectrometry (SR-XRF) to obtain elemental mass concentrations with the goal of addressing the contribution of the toxic metals to the fine aerosols. The data set allows a comprehensive analysis of particulate matter, giving information on temporal variations of PM2.5 mass concentration and chemical composition. The speciation found in this aerosol fraction is used to explore the sources responsible for the PM levels as well as their seasonal dependence applying a receptor model analysis to the measurements. Four sources have been identified being their contributions: traffic: 33.9 %, secondary aerosols/biomass burning: 35.1 %, mineral dust: 15.3 % and industry: 15.7 %. In addition, from May to August 2011, aerosols were collected in two additional size fractions (PM0.25-0.5, PM0.5-1) to investigate the toxic metal contributions to the finer fractions.  As far as we know, the present work represents the first long term study of PM2.5 performed in Córdoba investigating the elemental mass concentrations temporal variability as well as the speciation in the finer aerosol fractions. An important result of this work is that toxic metals make an important contribution to the finest (PM0.25-0.5) size fraction.