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An amorphous solid state of biogenic secondary organic aerosol particles


Secondary organic aerosol (SOA) particles are formed in the atmosphere from condensable oxidation products of anthropogenic and biogenic volatile organic compounds (VOCs)1,2,3,4,5,6,7. On a global scale, biogenic VOCs account for about 90% of VOC emissions1,8 and of SOA formation (90 billion kilograms of carbon per year)1,2,3,4. SOA particles can scatter radiation and act as cloud condensation or ice nuclei, and thereby influence the Earth’s radiation balance and climate1,2,5,9,10. They consist of a myriad of different compounds with varying physicochemical properties, and little information is available on the phase state of SOA particles. Gas–particle partitioning models usually assume that SOA particles are liquid1,5,11, but here we present experimental evidence that they can be solid under ambient conditions. We investigated biogenic SOA particles formed from oxidation products of VOCs in plant chamber experiments and in boreal forests within a few hours after atmospheric nucleation events. On the basis of observed particle bouncing in an aerosol impactor and of electron microscopy we conclude that biogenic SOA particles can adopt an amorphous solid—most probably glassy—state. This amorphous solid state should provoke a rethinking of SOA processes because it may influence the partitioning of semi-volatile compounds, reduce the rate of heterogeneous chemical reactions, affect the particles’ ability to accommodate water and act as cloud condensation or ice nuclei, and change the atmospheric lifetime of the particles12,13,14,15. Thus, the results of this study challenge traditional views of the kinetics and thermodynamics of SOA formation and transformation in the atmosphere and their implications for air quality and climate.

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Figure 1: Observations and interpretation of particle bounce of SOA and reference particles.
Figure 2: SEM images of plant chamber SOA particles and atmospheric SOA particles.


  1. 1

    Hallquist, M. et al. The formation, properties and impact of secondary organic aerosol: current and emerging issues. Atmos. Chem. Phys. 9, 5155–5236 (2009)

    ADS  CAS  Article  Google Scholar 

  2. 2

    Kanakidou, M. et al. Organic aerosol and global climate modelling: a review. Atmos. Chem. Phys. 5, 1053–1123 (2005)

    ADS  CAS  Article  Google Scholar 

  3. 3

    Kavouras, G. I., Mihalopoulos, N. & Stephanou, E. G. Formation of atmospheric particles from organic acids produced by forest. Nature 395, 683–686 (1998)

    ADS  CAS  Article  Google Scholar 

  4. 4

    Claeys, M. et al. Formation of secondary organic aerosols through photooxidation of isoprene. Science 303, 1173–1176 (2004)

    ADS  CAS  Article  Google Scholar 

  5. 5

    Jimenez, J. L. et al. Evolution of organic aerosols in the atmosphere. Science 326, 1525–1529 (2009)

    ADS  CAS  Article  Google Scholar 

  6. 6

    Laaksonen, A. et al. The role of VOC oxidation products in continental new particle formation. Atmos. Chem. Phys. 8, 2657–2665 (2008)

    ADS  CAS  Article  Google Scholar 

  7. 7

    Tunved, P. et al. High natural aerosol loading over boreal forests. Science 312, 261–263 (2006)

    ADS  CAS  Article  Google Scholar 

  8. 8

    Guenther, A. et al. A global model of natural volatile organic compound emissions. J. Geophys. Res. 100 (D5). 8873–8892 (1995)

    ADS  CAS  Article  Google Scholar 

  9. 9

    Fuzzi, S. et al. Critical assessment of the current state of scientific knowledge, terminology, and research needs concerning the role of organic aerosols in the atmosphere, climate, and global change. Atmos. Chem. Phys. 6, 2017–2038 (2006)

    ADS  CAS  Article  Google Scholar 

  10. 10

    Intergovernmental Panel on Climate Change (IPCC). Climate Change 2007: The Physical Science Basis Ch. 2 161–177 Ch. 7 556–564 (Cambridge University Press, 2007)

  11. 11

    Pankow, J. F. An absorption model of the gas/aerosol partitioning involved in the formation of secondary organic aerosol. Atmos. Environ. 28, 189–193 (1994)

    ADS  CAS  Article  Google Scholar 

  12. 12

    Zahardis, J. & Petrucci, G. A. The oleic acid-ozone heterogeneous reaction system: products, kinetics, secondary chemistry, and atmospheric implications of a model system—a review. Atmos. Chem. Phys. 7, 1237–1274 (2007)

    ADS  CAS  Article  Google Scholar 

  13. 13

    Zobrist, B., Marcolli, C., Pedernera, D. A. & Koop, T. Do atmospheric aerosols form glasses? Atmos. Chem. Phys. 8, 5221–5244 (2008)

    ADS  CAS  Article  Google Scholar 

  14. 14

    Murray, B. J. Inhibition of ice crystallisation in highly viscous aqueous organic acid droplets. Atmos. Chem. Phys. 8, 5423–5433 (2008)

    ADS  CAS  Article  Google Scholar 

  15. 15

    Mikhailov, E., Vlasenko, S., Martin, S. T., Koop, T. & Pöschl, U. Amorphous and crystalline aerosol particles interacting with water vapor: conceptual framework and experimental evidence for restructuring, phase transitions and kinetic limitations. Atmos. Chem. Phys. 9, 9491–9522 (2009)

    ADS  CAS  Article  Google Scholar 

  16. 16

    Joutsensaari, J. et al. Nanoparticle formation by ozonolysis of inducible plant volatiles. Atmos. Chem. Phys. 5, 1489–1495 (2005)

    ADS  CAS  Article  Google Scholar 

  17. 17

    Mentel, Th, F. et al. Photochemical production of aerosols from real plant emissions. Atmos. Chem. Phys. 9, 4387–4406 (2009)

    ADS  Article  Google Scholar 

  18. 18

    Dahneke, B. Capture of aerosol particles by surfaces. J. Colloid Interf. Sci. 37, 342–347 (1971)

    ADS  CAS  Article  Google Scholar 

  19. 19

    Stein, S. W., Turpin, J. B., Cai, X., Huang, P. F. & McMurry, P. H. Measurements of relative humidity dependent bounce and density for atmospheric particles using DMA-impactor technique. Atmos. Environ. 28, 1739–1746 (1994)

    ADS  CAS  Article  Google Scholar 

  20. 20

    Marcolli, C., Luo, B. P. & Peter, T. Mixing of the organic aerosol fractions: liquids as the thermodynamically stable phases. J. Phys. Chem. A 108, 2216–2224 (2004)

    CAS  Article  Google Scholar 

  21. 21

    Kalberer, M. et al. Identification of polymers as major components of atmospheric organic aerosols. Science 303, 1659–1662 (2004)

    ADS  CAS  Article  Google Scholar 

  22. 22

    Hari, P. & Kulmala, M. Station for measuring ecosystem-atmosphere relations (SMEAR II). Boreal Environ. Res. 10, 315–322 (2005)

    CAS  Google Scholar 

  23. 23

    Pankow, J. F. Review and comparative analysis of the theories of partitioning between the gas and aerosol particulate phases in the atmosphere. Atmos. Environ. 21, 2275–2283 (1987)

    ADS  CAS  Article  Google Scholar 

  24. 24

    Ehn, M. et al. Hygroscopic properties of ultrafine particles in the boreal forest: diurnal variation, solubility and the influence of sulfuric acid. Atmos. Chem. Phys. 7, 211–222 (2007)

    ADS  CAS  Article  Google Scholar 

  25. 25

    Hämeri, K. & Väkevä, M. Ultrafine aerosol particle hygroscopicity and volatility in boreal forest. Rep. Ser. Aerosol Sci. 47, 47–59 (2000)

    Google Scholar 

  26. 26

    Bahreini, R. et al. Measurements of secondary organic aerosol from oxidation of cycloalkanes, terpenes, and m-xylene using an aerodyne aerosol mass spectrometer. Environ. Sci. Technol. 39, 5674–5688 (2005)

    ADS  CAS  Article  Google Scholar 

  27. 27

    Maria, S. F., Russell, L. M., Gilles, M. K. & Myneni, S. C. B. Organic aerosol growth mechanisms and their climate-forcing implications. Science 306, 1921–1924 (2004)

    ADS  CAS  Article  Google Scholar 

  28. 28

    Parker, R. & Ring, S. G. Diffusion in maltose-water mixtures at temperatures close to the glass transition. Carbohydr. Res. 273, 147–155 (1995)

    CAS  Article  Google Scholar 

  29. 29

    Shiraiwa, M., Pfrang, C. & Pöschl, U. Kinetic multi-layer model of aerosol surface and bulk chemistry (KM-SUB): the influence of interfacial transport and bulk diffusion on the oxidation of oleic acid by ozone. Atmos. Chem. Phys. 10, 3673–3691 (2010)

    ADS  CAS  Article  Google Scholar 

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We acknowledge support by the Academy of Finland (decision numbers 110763, 111543, 131019, 218115 and Centre of Excellence Programme) and the Maj and Tor Nessling foundation. We also acknowledge J. Keskinen and A. Arffman for fruitful discussions concerning impactor performance, H. Kuuluvainen for his help in bounce factor measurements, K. Rissa for SEM imaging, L. Hao, P. Tiitta, A. Kortelainen and P. Miettinen for aerosol mass spectrometer analyses and their help during experiments, J. Jokiniemi, U. Tapper and J. Lyyränen (VTT Technical Research Centre of Finland) for the development of SEM sample collection and image analysis methods, A. Diekmann for the differential scanning calorimeter measurements and T. Wagner for providing polystyrene samples.

Author information




J.J., AV, J.K. and P.Y.-P. designed and conducted the plant chamber measurements and A.V., J.J., J.K., and M.K. the atmospheric measurements; A.V. developed the bounce factor concept; T.K. contributed the DSC data; J.K., A.V., J.J., J.L., P.Y.-P. and T.K. contributed to the interpretation of data; A.V. and T.K. wrote the manuscript; J.J., J.K., J.M.M., U.P., M.K., D.R.W. and A.L. discussed data and commented on the manuscript; A.L., M.K. and J.K.H. provided the working environment and financial support.

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Correspondence to Annele Virtanen or Thomas Koop.

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The authors declare no competing financial interests.

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Supplementary Information

This file contains a Supplementary Discussion, Supplementary Figures 1-8 with legends, Supplementary Methods, Supplementary Tables 1-2 and additional references. (PDF 1819 kb)

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Virtanen, A., Joutsensaari, J., Koop, T. et al. An amorphous solid state of biogenic secondary organic aerosol particles. Nature 467, 824–827 (2010).

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