Quantitative assessment of organosulfates in size-segregated rural fine aerosol H. Lukács, A. Gelencsér, A. Hoffer, G. Kiss, K. Horváth, and Z. Hartyáni Department of Earth and Environmental Sciences, Air Chemistry Group of the Hungarian Academy of Sciences University of Pannonia, Veszprém, Hungary
Abstract. Organosulfates have recently come into the focus of organic aerosol research
as potentially important components of water-soluble secondary organic
aerosol (SOA) which now dominate tropospheric fine aerosol. Their presence
has been confirmed by the identification of sulfate esters of abundant
biogenic carbonyl compounds in both smog chamber and continental aerosol.
However, none of the studies have been able to determine the mass
contribution of organosulfates to SOA.
In this paper, as possibly the very first attempt to quantify organosulfates
in ambient aerosol, we inferred the mass concentrations of organosulfates by
concurrently determining mass concentrations of total sulfur, sulfate and
methanesulfonate in rural fine aerosol using two highly sensitive analytical
techniques. Although uncertainties were relatively large, we found that mass
concentrations of organosulfates in water-soluble fine aerosol ranged from
0.02 μgS m−3 to 0.09 μgS m−3 yielding a mass
contribution of 6–12% to bulk sulfur concentrations (or 6–14% to
sulfate concentrations). The inferred size distribution of organosulfates
suggested that they possibly form in heterogeneous reactions from
semi-volatile carbonyl compounds with subsequent or concurrent condensation
of gaseous sulfuric acid producing a refractory organic film on particle
Citation: Lukács, H., Gelencsér, A., Hoffer, A., Kiss, G., Horváth, K., and Hartyáni, Z.: Quantitative assessment of organosulfates in size-segregated rural fine aerosol, Atmos. Chem. Phys., 9, 231-238, doi:10.5194/acp-9-231-2009, 2009.