Composition and mass size distribution of nitrated and oxygenated aromatic compounds in ambient particulate matter from southern and central Europe – implications for the origin

Abstract

Abstract. Nitro-monoaromatic hydrocarbons (NMAHs), such as nitrocatechols, nitrophenols and nitrosalicylic acids, are important constituents of atmospheric particulate matter (PM) water-soluble organic carbon (WSOC) and humic-like substances (HULIS). Nitrated and oxygenated derivatives of polycyclic aromatic hydrocarbons (NPAHs and OPAHs) are toxic and ubiquitous in the ambient air; due to their light absorption properties, together with NMAHs, they are part of aerosol brown carbon (BrC). We investigated the winter concentrations of these substance classes in size-resolved PM from two urban sites in central and southern Europe, i.e. Mainz (MZ), Germany, and Thessaloniki (TK), Greece. The total concentration of 11 NMAHs (∑11NMAH concentrations) measured in PM10 and total PM were 0.51–8.38 and 12.1–72.1 ng m−3 at the MZ and TK sites, respectively, whereas ∑7OPAHs were 47–1636 and 858–4306 pg m−3, and ∑8NPAHs were ≤90 and 76–578 pg m−3, respectively. NMAHs contributed 0.4 % and 1.8 % to the HULIS mass at MZ and TK, respectively. The mass size distributions of the individual substances generally peaked in the smallest or second smallest size fraction i.e. <0.49 or 0.49–0.95 µm. The mass median diameter (MMD) of NMAHs was 0.10 and 0.27 µm at MZ and TK, respectively, while the MMDs of NPAHs and OPAHs were both 0.06 µm at MZ and 0.12 and 0.10 µm at TK. Correlation analysis between NMAHs, NPAHs, and OPAHs from one side and WSOC, HULIS, sulfate, and potassium from the other suggested that fresh biomass burning (BB) and fossil fuel combustion emissions dominated at the TK site, while aged air masses were predominant at the MZ site.

Nitrated monoaromatic hydrocarbons (nitrophenols, nitrocatechols, nitrosalicylic acids) in ambient air: levels, mass size distributions and inhalation bioaccessibility

“…1). These results are in agreement with previous reports from other urban sites in central and southern Europe (Kitanovski et al 2020) and China (Li et al 2016). The aerosol number size distributions (characterised in Fig.…”

“…The determination of NMAHs in the PM filter samples was done using a validated analytical procedure (Kitanovski et al 2012(Kitanovski et al , 2020 with small modifications. In short, a 1.5-cm 2 section of the filter was spiked with 4-nitrophenol-d 4 (IS; spiked mass, 100 ng) and extracted three times (5 min each) with 10 mL methanolic solution of EDTA (3.4 nmol mL −1 ) in an ultrasonic bath.…”

“…The targeted NMAHs, i.e. 2 NSAs, 4 NCs and 6 NPs (listed in Table S2 together with main physicochemical properties), were determined using an Agilent 1200 Series HPLC system (Agilent Technologies, Waldbronn, Germany) coupled to an Agilent 6130B single quadrupole mass spectrometer equipped with an electrospray ionisation (ESI) source (Kitanovski et al 2020). Atlantis T3 column (150 mm × 2.1 mm i.d., 3-μm particles size; Waters, Milford, USA), connected to an Atlantis T3 VanGuard pre-column (5 mm × 2.1 mm i.d., 3-μm particles size; Waters), was used for the separation of the targeted analytes.…”

“…NSAs may also be formed in secondary organic aerosols exposed to NO 3 radicals (Ramaswamy et al 2019). NMAHs may represent up to 1% and 2% of PM 10 mass and HULIS, respectively (Claeys et al 2012;Kitanovski et al 2012Kitanovski et al , 2020Kahnt et al 2013;Caumo et al 2016). NPs and NSAs are proven to have adverse effects on human health (estrogenic activity, carcinogenicity, cataract; Karim and Gupta 2001;Brüning et al 2002;Harrison et al 2005;Grundlingh et al 2011;Kovacic and Somanathan 2014), while little is known about the toxicology of NCs.…”

NPAHs and OPAHs in the atmosphere of two central European cities: Seasonality, urban-to-background gradients, cancer risks and gas-to-particle partitioning

“…rural, marine, urban) and in different seasons have shown that most (i.e. >80%) of particulate NOPAHs present in the air were bound to fine particles ( Albinet et al, 2008 ; Alves et al, 2016a ; Besis et al, 2017 ; Kitanovski et al, 2020 ; Lammel et al, 2020 , Lammel et al, 2017 ; Ringuet et al, 2012b ). Depending on availabilities, high volume air samplers (HVAS, Digitel DH77, flow rate of 30 m 3 h −1 at the Brno T site and the R site) or low volume air samplers (LVAS, Leckel MVS6 at Brno UB, LVS 3.1 Comde Derenda LVS/MVS at Ljubljana T and ECHO PM, Tecora at Ljubljana UB, all with a flow rate of 2.3 m 3 h −1 ) were used.…”