TY  - JOUR
AB  - In this paper, we investigate physico-chemical properties of particulate matter (PM) at an urban mixed site (UB) and two roadside (RS) sites during the 2015 Metro Manila Aerosol Characterization Experiment (MACE). Aerosol particle number size distributions (0.01-10 μm diameter) were measured using a combination of a mobility particle size spectrometer and aerodynamic particle size spectrometers. PM2.5 filter samples were analyzed for total mass, organic carbon (OC), elemental carbon (EC), water-soluble inorganic ions, and elemental species. Mass closure between the gravimetric mass, chemical composition, and mass concentration derived from the number size distribution was performed. We found that the bulk PM2.5 mass was dominated by carbonaceous materials, followed by secondary inorganic aerosols and crustal matter at all sites. The average OC/EC ratios at the RS sites (0.16-1.15) suggest that a major fraction of the aerosol mass at these sites derives from traffic sources, while the OC/EC ratio at the UB site (2.92) is indicative of a more aged aerosol, consistent with greater contribution from secondary organic carbon (SOC) formation. The ultrafine particles (UFPs, diameter < 100 nm) dominated (89-95%) the total particle number concentration at the three sites, highlighting the importance of such measurements in this region. However, UFPs have low mass contribution to PM2.5 (7-18%), while particles in the accumulation mode (diameter 100-1000 nm) accounted for most of the number-derived PM2.5 mass concentration (61-67%). On average, strong agreement between the chemically-derived mass and the gravimetric mass was found (slope = 1.02; r2 = 0.94). The number-derived mass concentration correlated well with the gravimetric PM2.5 mass (slope = 1.06; r2 = 0.81). These results highlight the need for more comprehensive PM characterization, particularly focusing on size-resolved chemical composition and particle number size distributions. The mass closure approach presented in this work provides a framework for a conversion between number size distributions and PM2.5 mass concentration in real time in an environment with similar characteristics.
AU  - Betito, G.*
AU  - Catipay-Jamero, G.*
AU  - Alas, H.*
AU  - Birmili, W.*
AU  - Cambaliza, M.O.*
AU  - Cayetano, M.*
AU  - Cohen, D.M.*
AU  - Cruz, M.*
AU  - Galvez, M.C.D.*
AU  - Jagonoy, A.*
AU  - Kecorius, S.
AU  - Lorenzo, G.R.*
AU  - Madueno, L.*
AU  - Müller, T.*
AU  - Pabroa, P.C.*
AU  - Simpas, J.B.*
AU  - Sorooshian, A.*
AU  - Tamayo, E.G.*
AU  - Vallar, E.A.*
AU  - Weinhold, K.*
AU  - Wiedensohler, A.*
C1  - 74831
C2  - 57614
CY  - Thomas Graham House, Science Park, Milton Rd, Cambridge Cb4 0wf, Cambs, England
SP  - 714-728
TI  - Two approaches to mass closure analysis for carbon-rich aerosol in Metro Manila, Philippines.
JO  - Environ. Sci. - Atmospheres
VL  - 5
IS  - 6
PB  - Royal Soc Chemistry
PY  - 2025
SN  - 2634-3606
ER  - 

TY  - JOUR
AB  - The enforcement of global fuel sulfur content (FSC) regulations has significantly reduced SO2 and particulate matter (PM) emissions from ships. However, the impact of the International Maritime Organization's (IMO) sulfur reduction policy on gaseous hydrocarbon emissions, including volatile and intermediate volatility organic compounds (VOCs/IVOCs), remains underexplored. In this study, a 4-stroke single cylinder marine engine was operated using marine gas oil (MGO, FSC = 0.01%) and low-sulfur heavy fuel oil (LS-HFO, FSC = 0.5%) across various engine loads, ranging from 20 kW to a maximum of 80 kW. Emissions were photochemically aged in the oxidation flow reactor "PEAR," simulating an equivalent photochemical aging period from 1.4 +/- 0.2 to 4.6 +/- 0.8 days related to the OH exposure. Emission factors (EFs) of all targeted VOCs/IVOCs varied significantly, ranging from 20.0 +/- 2.5 to 180 +/- 20 mg kWh-1 and from 26.0 +/- 11.0 to 280 +/- 100 mg kWh-1 from a high (80 kW) to low engine load (20 kW) for MGO and LS-HFO, respectively. Monoaromatics dominated total fresh emissions for MGO (64%) and LS-HFO (76%), followed by alkanes. Naphthalene and alkylated naphthalene content declined more than monoaromatic and alkane content, thus changing the VOC/IVOC emission pattern after photochemical aging. Estimated SOA from targeted VOC/IVOC precursors accounted for 41% of the measured secondary organic aerosol (SOA) for MGO, while a lower contribution (34%) was observed for LS-HFO at 20 kW engine load, highlighting the role of unmeasured VOCs/IVOCs in SOA formation. Expanding the research on the effects of atmospheric aging on marine emissions will offer valuable insights into this underexplored area.
AU  - Shukla, D.
AU  - Czech, H.
AU  - Kokkola, T.*
AU  - Bauer, M.*
AU  - Paul, A.*
AU  - Etzien, U.*
AU  - Ihalainen, M.*
AU  - Fang, Z.*
AU  - Hartikainen, A.*
AU  - Gawlitta, N.
AU  - Hohaus, T.*
AU  - Rudich, Y.*
AU  - Streibel, T.
AU  - Buchholz, B.*
AU  - Sippula, O.*
AU  - Ovrevik, J.*
AU  - Schnelle-Kreis, J.
AU  - Zimmermann, R.
C1  - 75414
C2  - 57963
CY  - Thomas Graham House, Science Park, Milton Rd, Cambridge Cb4 0wf, Cambs, England
SP  - 973-986
TI  - Emission speciation of volatile and intermediate volatility organic compounds from a marine engine: Effect of engine load, fuel type and photochemical aging.
JO  - Environ. Sci. - Atmospheres
VL  - 5
IS  - 9
PB  - Royal Soc Chemistry
PY  - 2025
SN  - 2634-3606
ER  - 

TY  - JOUR
AB  - We investigated the fuel-dependent single-particle mass spectrometric signatures of polycyclic aromatic hydrocarbons (PAHs) from the emissions of a research ship engine operating on marine gas oil (MGO), hydrotreated vegetable oil (HVO) and two heavy fuel oils (HFO), one with compliant and one with non-compliant fuel sulfur content. The PAH patterns are only slightly affected by the engine load and particle size, and contain sufficient dissimilarity to discriminate between the marine fuels used in our laboratory study. Hydrotreated vegetable oil (HVO) produced only weak PAH signals, supporting that fuel residues, rather than combustion conditions, determine the PAH emissions. The imprint of the fuel in the resulting PAH signatures, combined with novel single-particle characterization capabilities for inorganic and organic components, opens up new opportunities for source apportionment and air pollution monitoring. The approach is independent of metals, the traditional markers of ship emissions, which are becoming less important as new emission control policies are implemented and fuels become more diverse.
AU  - Anders, L.
AU  - Schade, J.
AU  - Rosewig, E.I.
AU  - Schmidt, M.
AU  - Irsig, R.*
AU  - Jeong, S.
AU  - Käfer, U.
AU  - Gröger, T.M.
AU  - Bendl, J.
AU  - Saraji-Bozorgzad, M.
AU  - Adam, T.
AU  - Etzien, U.*
AU  - Czech, H.
AU  - Buchholz, B.*
AU  - Streibel, T.
AU  - Passig, J.
AU  - Zimmermann, R.
C1  - 70818
C2  - 55681
CY  - Thomas Graham House, Science Park, Milton Rd, Cambridge Cb4 0wf, Cambs, England
TI  - Polycyclic aromatic hydrocarbons as fuel-dependent markers in ship engine emissions using single-particle mass spectrometry.
JO  - Environ. Sci. - Atmospheres
PB  - Royal Soc Chemistry
PY  - 2024
SN  - 2634-3606
ER  - 

TY  - JOUR
AB  - Oxidation flow reactors (OFRs) have been increasingly used to conduct research on secondary aerosol formation potential and composition in laboratory and field studies by exposing aerosols to high levels of oxidants in short time periods. In order to assess the atmospheric relevance of the triggered chemical reactions, kinetic models have been developed to reveal the production of atmospheric oxidants and the fate of volatile organic compounds (VOCs). However, it is unknown how different OFR conditions generating the same OH exposure affect the chemical and physical properties of the secondary aerosol particle phase because the model is based on gas phase chemistry. Toluene as a well-investigated precursor of secondary organic aerosols (SOAs) was aged in the high-volume OFR “PEAR” at three different external OH reactivities (OHRext) and in an environmental chamber at the same OH exposure of (1.09 ± 0.09) × 1011 s cm−3. These specific OFR conditions altered the majority of the investigated chemical and physical properties of the toluene-derived SOA (tol-SOA). However, OFR-aging at low OHRext associated with atmospherically relevant conditions did not lead to physical and chemical SOA properties most similar to chamber-generated SOAs at the same low OHRext. Particularly, for the most detailed chemical analysis by electrospray (ESI) high-resolution Orbitrap mass spectrometry (HRMS), tol-SOA from the PEAR at high OHRext, deviating from atmospherically relevant conditions, and the chamber were most different to tol-SOA from the PEAR with low and medium OHRext. Our study challenges the concept of atmospherically relevant OFR aerosol aging and motivates further exploration of OFR conditions on secondary aerosol composition.
AU  - Czech, H.
AU  - Yli-Pirilä, P.*
AU  - Tiitta, P.*
AU  - Ihalainen, M.*
AU  - Hartikainen, A.*
AU  - Schneider, E.*
AU  - Martens, P.*
AU  - Paul, A.*
AU  - Hohaus, T.*
AU  - Rüger, C.P.*
AU  - Jokiniemi, J.*
AU  - Zimmermann, R.
AU  - Sippula, O.*
C1  - 70863
C2  - 55745
CY  - Thomas Graham House, Science Park, Milton Rd, Cambridge Cb4 0wf, Cambs, England
TI  - The effect of aging conditions at equal OH exposure in an oxidation flow reactor on the composition of toluene-derived secondary organic aerosols.
JO  - Environ. Sci. - Atmospheres
PB  - Royal Soc Chemistry
PY  - 2024
SN  - 2634-3606
ER  - 

TY  - JOUR
AB  - The most recent European regulation, the Euro 6d emission standard, requires all gasoline direct injection (GDI) vehicles to use both a three-way catalyst (TWC) and a gasoline particle filter (GPF) as exhaust aftertreatment. These aftertreatment methods are aimed at reducing NOx and primary particle emissions. However, the formation of secondary organic aerosols (SOAs) from the volatile organic compound (VOC) emissions of a Euro 6d compliant GDI vehicle, factory equipped with a GPF is not yet investigated. Therefore, to explore the SOA formation and effects of the GPF, the exhaust of a Euro 6d compliant GDI vehicle was characterized at 4 different steady state speeds, idling (0 km h−1), 50, 80 and 100 km h−1. The exhaust was oxidised in a photochemical emission aging flow tube reactor (PEAR) by reactions with OH radicals equivalent of 2.2 days of atmospheric day time oxidation. It was found that the GPF completely removes primary particles larger than 10 nm, at all investigated vehicle speeds. However, significant SOA was formed after oxidation, with the highest SOA formation potential per kg fuel consumed at 50 km h−1. The main SOA precursors were determined to be toluene, xylene and trimethyl-benzene which were found to account for at least 50% of SOA formed at all driving speeds. Furthermore, high emissions of ammonia (NH3) could be observed in the exhaust under all driving conditions which resulted in the subsequent formation of ammonium nitrate (NH4NO3) after aging. The formation of NH4NO3 additionally facilitated the co-condensation of organic gas phase products after OH oxidation enhancing SOA mass even further.
AU  - Paul, A.*
AU  - Fang, Z.*
AU  - Martens, P.*
AU  - Mukherjee, A.*
AU  - Jakobi, G.
AU  - Ihalainen, M.*
AU  - Kortelainen, M.*
AU  - Somero, M.*
AU  - Yli-Pirilä, P.*
AU  - Hohaus, T.*
AU  - Czech, H.
AU  - Kalberer, M.*
AU  - Sippula, O.*
AU  - Rudich, Y.*
AU  - Zimmermann, R.
AU  - Kiendler-Scharr, A.*
C1  - 70890
C2  - 55791
CY  - Thomas Graham House, Science Park, Milton Rd, Cambridge Cb4 0wf, Cambs, England
TI  - Formation of secondary aerosol from emissions of a Euro 6d-compliant gasoline vehicle with a particle filter.
JO  - Environ. Sci. - Atmospheres
PB  - Royal Soc Chemistry
PY  - 2024
SN  - 2634-3606
ER  - 

TY  - JOUR
AB  - Using novel ionization technologies in single-particle mass spectrometry (SPMS), we analyzed the polycyclic aromatic hydrocarbons (PAHs) on individual particles from a research ship engine running on marine gasoil (MGO). We found a rather uniform PAH signature on the majority of particles. The PAH pattern is stable for all engine loads and particle sizes and differs from typical signatures of other pyrogenic and petrogenic PAH sources. Based on this observation, we conducted a field experiment and observed that the appearance of this PAH signature is associated with marine air masses. Moreover, we could detect the plume of a single ship passage at 15-20 km distance by the transient appearance of particles with the same distinct PAH profile. Consequently, we suggest the use of the specific PAH pattern as a new marker to detect and monitor ship emissions, independent of the conventional metal signatures that are not applicable for compliant fuels in emission control areas and coastal waters.
AU  - Anders, L.
AU  - Schade, J.
AU  - Rosewig, E.I.
AU  - Kröger-Badge, T.
AU  - Irsig, R.*
AU  - Jeong, S.
AU  - Bendl, J.*
AU  - Saraji-Bozorgzad, M.
AU  - Huang, J.H.*
AU  - Zhang, F.Y.*
AU  - Wang, C.C.*
AU  - Adam, T.
AU  - Sklorz, M.
AU  - Etzien, U.*
AU  - Buchholz, B.*
AU  - Czech, H.
AU  - Streibel, T.
AU  - Passig, J.
AU  - Zimmermann, R.
C1  - 68369
C2  - 53641
CY  - Thomas Graham House, Science Park, Milton Rd, Cambridge Cb4 0wf, Cambs, England
SP  - 1134-1144
TI  - Detection of ship emissions from distillate fuel operation via single-particle profiling of polycyclic aromatic hydrocarbons.
JO  - Environ. Sci. - Atmospheres
VL  - 3
IS  - 8
PB  - Royal Soc Chemistry
PY  - 2023
SN  - 2634-3606
ER  -