2014 Progress Report: Sources and Radiative Properties of Organosulfates in the Atmosphere

EPA Grant Number: R835401
Title: Sources and Radiative Properties of Organosulfates in the Atmosphere
Investigators: Stone, Elizabeth A
Institution: University of Iowa
EPA Project Officer: Chung, Serena
Project Period: April 1, 2013 through March 31, 2016
Project Period Covered by this Report: April 1, 2014 through June 30,2015
Project Amount: $300,000
RFA: Anthropogenic Influences on Organic Aerosol Formation and Regional Climate Implications (2012) RFA Text |  Recipients Lists
Research Category: Air Quality and Air Toxics , Global Climate Change , Climate Change , Air


This project focuses on the measurement of organosulfates in the 2013 Southern Oxidant & Aerosol Study (SOAS). The aim is to identify the biogenic and anthropogenic emissions sources that lead to formation of organosulfates and how mixtures of biogenic and anthropogenic emissions lead to secondary organic aerosol formation. Laboratory studies will investigate the impacts of organosulfates on climate, including their radiative properties, light absorption, and their hygroscopic growth. 

Progress Summary:

To allow for organosulfate quantification in ambient aerosol, a novel set of biogenic organosulfate molecules has been synthesized. The target molecules include small, isoprene-derived organosulfates that have previously been identified in smog chamber and ambient aerosol studies and other closely related compounds. To date, standards for glycolic acid sulfate, lactic acid sulfate, hydroxyacetone sulfate, acetoin sulfate, butenediol sulfate, and oxirane sulfate have been developed. To support future standard development, we have recently reported an efficient protocol for organosulfate synthesis and isolation in the potassium salt form (Hettiyadura, et al. 2015). These standards are among the first organosulfate standards developed, which are critical to the development of accurate measurement methods and characterizing their climate-relevant properties. In addition, these standards have been shared among the Southeastern Oxidant and Aerosol Study (SOAS) investigators for evaluation of their response in laboratory- and field-based instruments.

Synthesized and commercially available organosulfate standards have undergone characterization of their physical and climate-relevant properties. Light absorption in the ultraviolet and visible ranges has been examined spectroscopically. Hygroscopic water uptake has been evaluated using the Multi-Analysis Aerosol Reactor System (MAARS) and hygroscopic growth factors have been modeled. Results of these experiments are the subject of a manuscript in preparation.

With the newly developed organosulfate standards, an ultra-performance liquid chromatography (UPLC) and tandem mass spectrometry (MS/MS) method has been developed for the separation, identification, and quantification of atmospheric organosulfates in ambient aerosol (Hettiyadura, et al. 2015). Importantly, the analytical method is demonstrated to be linear across a range of concentrations that encompass levels observed in atmospheric aerosols, has a low limit of detection, and excellent reproducibility for most compounds. In parallel, an efficient method of preparing ambient samples for UPLC-MS/MS analysis has been developed, validated, and tested on ambient samples collected in Centreville, Alabama, during the SOAS. The analysis of ambient PM2.5 samples collected on 10-11 July 2013 in Centreville confirmed the presence of hydroxyacetone sulfate in ambient aerosol for the first time at concentrations ranging 2.7 – 5.8 ng m-3. Lactic acid sulfate was the most abundant organosulfate quantified (9.6 – 19 ng m-3), followed by glycolic acid sulfate (8 – 14 ng m-3).

Complementary measurements of PM2.5, including organic carbon (OC), elemental carbon (EC), and organic species have also been completed through this research project. We have analyzed 110 samples for elemental and organic carbon (EC and OC), 30 samples for water-soluble organic carbon (WSOC), and 52 samples for organic species using gas chromatography mass spectrometry (GCMS). The quantified organic compounds include 13 n-alkanes which serve as markers of vegetative detritus, 20 n-alkanoic acids some of which are emitted by food cooking and vegetation, six unsaturated fatty acids, seven dicarboxylic acids which are suggested SOA tracers, 11 SOA tracers of biogenic gases, levoglucosan and five sterols that are tracers for biomass burning. These data provide insight to the bulk composition of PM2.5, will be used in source apportionment modeling, and provide opportunities for measurement inter-comparisons with other SOAS researchers to assess sampling and measurement artifacts and the accuracy of emerging methods of aerosol analysis.

Future Activities:

  • Quantification of organosulfates in PM2.5 samples in Centreville during SOAS following the day/night and intensive periods and analysis of these data to evaluate changes in OS concentrations in response to sulfur gas emissions, aerosol acidity, and meteorological conditions (i.e., temperature, relative humidity, and sunlight).
  • Receptor-based source apportionment modeling by two approaches (positive matrix factorization and chemical mass balance) to quantify anthropogenic and biogenic contributions to organic aerosol (particularly SOA).
  • Preparation and submission of manuscripts for publication.
  • Measurement inter-comparison with other SOAS researchers. 

Journal Articles on this Report : 3 Displayed | Download in RIS Format

Other project views: All 22 publications 6 publications in selected types All 6 journal articles
Type Citation Project Document Sources
Journal Article Budisulistiorini SH, Li X, Bairai ST, Renfro J, Liu Y, Liu YJ, McKinney KA, Martin ST, McNeill VF, Pye HOT, Nenes A, Neff ME, Stone EA, Mueller S, Knote C, Shaw SL, Zhang Z, Gold A, Surratt JD. Examining the effects of anthropogenic emissions on isoprene-derived secondary organic aerosol formation during the 2013 Southern Oxidant and Aerosol Study (SOAS) at the Look Rock, Tennessee ground site. Atmospheric Chemistry and Physics 2015;15(15):8871-8888. R835401 (2014)
R835401 (Final)
R835404 (2014)
R835404 (2015)
R835404 (Final)
R835410 (2013)
  • Full-text: ACP-Full Text PDF
  • Abstract: ACP-Abstract
  • Other: ResearchGate-Abstract & Full Text PDF
  • Journal Article Hettiyadura APS, Stone EA, Kundu S, Baker Z, Geddes E, Richards K, Humphry T. Determination of atmospheric organosulfates using HILIC chromatography with MS detection. Atmospheric Measurement Techniques 2015;8(6):2347-2358. R835401 (2014)
    R835401 (Final)
  • Full-text: EGU-Full Text PDF
  • Abstract: EGU-Abstract
  • Other: ResearchGate-Full Text PDF
  • Journal Article Washenfelder RA, Attwood AR, Brock CA, Guo H, Xu L, Weber RJ, Ng NL, Allen HM, Ayres BR, Baumann K, Cohen RC, Draper DC, Duffey KC, Edgerton E, Fry JL, Hu WW, Jimenez JL, Palm BB, Romer P, Stone EA, Wooldridge PJ, Brown SS. Biomass burning dominates brown carbon absorption in the rural southeastern United States. Geophysical Research Letters 2015;42(2):653-664. R835401 (2014)
    R835401 (Final)
    R835399 (2014)
    R835399 (Final)
  • Full-text: ResearchGate-Full Text PDF
  • Abstract: Wiley Online-Abstract
  • Other: Wiley Online-Full Text PDF
  • Supplemental Keywords:

    Air quality, global climate, troposphere, analytical chemistry, Southern Oxidant & Aerosol Study (SOAS), organosulfates

    Relevant Websites:

    Stone Research Group Exit

    Progress and Final Reports:

    Original Abstract
  • 2013 Progress Report
  • Final Report