Identification of secondary fatty alcohols in atmospheric aerosols in temperate forests

Abstract

Abstract. Fatty alcohols (FAs) are major components of surface lipids (waxes) and can act as surface-active organic aerosols in the atmosphere, influencing chemical reactions, particle lifetimes, and the formation of cloud droplets and ice nuclei. However, studies on the composition and source of the FAs in atmospheric aerosols are very limited. In this study, we identified five secondary FAs (SFAs) with C27 and C29 from aerosol samples collected throughout 1 year at two different deciduous forest sites in Japan. Fatty diols, such as n-heptacosan-5,10-diol, were identified in atmospheric aerosols for the first time. Among the identified SFAs, n-nonacosan-10-ol was the most abundant compound, followed by n-nonacosan-5-10-diol at both of the forest sites. Concentrations of the SFAs exhibited distinct seasonal variation, with pronounced peaks during the growing season at each forest site. The SFAs showed significant correlation with sucrose, which is used as a molecular tracer of pollen. A significant fraction of the SFAs was attributed to the submicrometer particles in the growing season. The results indicate that they originated mostly from plant waxes and could be used as useful tracers for primary biological aerosol particles.

Origin of water-soluble organic aerosols at the Maïdo high-altitude observatory, Réunion Island, in the tropical Indian Ocean

“…The molecular compounds include 2methyltetrol, pinic acid, pinonic acid, and 3-methyl-1,2,3butanetricarboxylic acid (3-MBTCA), as oxidation products of biogenic VOCs (Yu et al, 1999;Claeys et al, 2004Szmigielski et al, 2007). In addition, tracers of primary biogenic emissions, such as glucose (Simoneit et al, 2004) and n-nonacosan-10-ol (Miyazaki et al, 2019), were also measured. The -COOH and -OH functional groups in the extracts were reacted with N,O-bis-(trimethylsilyl) trifluoroacetamide to form trimethylsilyl (TMS) esters and TMS ethers, respectively (Fu et al, 2011).…”

Emerging investigator series: surfactants, films, and coatings on atmospheric aerosol particles: a review

“…Direct observations and source apportionment studies of surfactants in terrestrial ambient aerosol particles are limited, but previous work demonstrates the ubiquity and significance of surfactants from both biogenic and anthropogenic sources in terrestrial ambient aerosol particles as well as the importance of seasonality in determining aerosol surfactant composition. Miyazaki et al 450 were the first group to identify and study seasonal variations in secondary fatty alcohols, which can act as surface-active organics, in ambient aerosol from two deciduous forest sites in rural Japan. Over the course of a one-year field study, they observed pronounced seasonal trends in surfactant concentrations, with increased emissions during the peak growing season.…”

“…The source of the surfactants was attributed to plant waxes and primary biological aerosols based on positive correlations with sucrose. 450 Pérez Pastor et al 478 characterized organic aerosol in rural Spain and observed peak emissions during winter due to domestic combustion of olive waste with contributions from SOA, lubricating oil, and soil organics. Kroflič et al 235 also observed the influence of seasonality in measured surfactant concentrations for size-segregated ambient aerosol particles ranging from approximately PM 0.1 to PM 10 collected at an urban site in Slovenia.…”

“…443 Gérard and coworkers subsequently applied their targeted extraction and colorimetric method to investigate PM 1 aerosol in an expanded eld scope with several urban, rural, and coastal sites in Europe focusing on amphiphilic surfactants. 443,446 Various types of mass spectrometry, [447][448][449][450][451][452] electrochemical methods, 235,453 micro-Raman spectroscopy, 454,455 AFM, 456 and TEM 457 have also been employed to characterize surfactants through both direct and indirect methods. These techniques provide quantitative information on ambient aerosol surfactants, which will enable improved understanding of surfactants' inuence on particle activation ability.…”

Origin of water-soluble organic aerosols at the Maïdo high-altitude observatory, Réunion Island in the tropical Indian Ocean

“…Factor 4 (F4) is characterized by the dominant contributions of 2-methyltetrol and n-nonacosan-10-ol. Miyazaki et al (2019) identified n-nonacosan-10-ol in forest aerosols, suggesting that they originated mostly from plant waxes and could be a tracer of primary biological aerosol particles. Consequently, F4 is referred to here as "terrestrial biogenic sources."…”