A study on the chemical profile and the derived health effects of heavy-duty machinery aerosol with a focus on the impact of alternative fuels

DATA AVAILABILITY: The datasets used and/or analyzed during the current study are available from the first author on reasonable request. (Please contact [email protected]).The combustion of petroleum-based fossil fuels is associated with a high environmental burden. Several alternative fuels, including synthetic fuels (e.g., gas-to-liquid, GTL) and biofuels (e.g., rapeseed methyl ester, RME) have been studied in the last few years. While the advantages for the environment (sustainability of biofuels) are well known, research on the resulting health effects from combustion aerosols of these alternative fuels is still scarce. Consequently, we investigated the chemical combustion profile from three distinct fuel types, including a petroleum-based fossil fuel (B0) and two alternative fuels (GTL, RME) under real exposure conditions. We sampled particulate matter (PM2.5, PM0.25) and the gas phase from heavy-duty machinery and evaluated the general pattern of volatile and semi-volatile organic compounds, elemental and organic carbon as well as a range of transition metals in the size segregated PM and/or gas phase. The use of comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry enabled us to classify distinct methylated PAHs in the PM samples and its high abundance, especially in the fine fraction of PM. We found that (methylated) PAHs were highly abundant in the PM of B0 compared to GTL and RME. Highest concentrations of targeted aromatic species in the gas phase were released from B0. In summary, we demonstrated that GTL and RME combustion released lower amounts of chemical compounds related to adverse health effects, thus, the substitution of petroleum-based fuels could improve air quality for human and the environment.The University of Pretoria and the National Research Foundation of South Africa. Open Access funding enabled and organized by Projekt DEAL.http://link.springer.com/journal/11869Chemistr

Emissions from a modern log wood masonry heater and wood pellet boiler : Composition and biological impact on air-liquid interface exposed human lung cancer cells

The consumption of wood fuel is markedly increasing in developing and industrialized countries. Known side effects of wood smoke inhalation manifest in proinflammatory signaling, oxidative stress, DNA damage and hence increased cancer risk. In this study, the composition and acute biological impact of emissions of state-of-the-art wood combustion compliances: masonry heater (MH) and pellet boiler (PB) were investigated. Therefore A549 cells were exposed to emission aerosols in an automated air-liquid interface exposure station followed by cytotoxicity, transcriptome and proteome analyses. In parallel, aerosols were subjected to a chemical and physical haracterization. Compared to PB, the MH combustion at the same dilution ratio resulted in a 3-fold higher particle mass concentration (PM2.5) and deposited dose (PB: 27 $\pm$ 2 ng/cm2, MH; 73 $\pm$ 12 ng/cm2). Additionally, the MH aerosol displayed a substantially larger concentration of aldehydes, polycyclic aromatic hydrocarbons (PAH) or oxidized PAH. Gene ontology analysis of transcriptome of A549 cells exposed to MH emissions revealed the activation of proinflammatory response and key signaling cascades MAP kinase and JAK-STAT. Furthermore, CYP1A1, an essential enzyme in PAH metabolism, was induced. PB combustion aerosol activated the proinflammatory marker IL6 and different transport processes. The proteomics data uncovered induction of DNA damage-associated proteins in response to PB and DNA doublestrand break processing proteins in response to MH emissions. Taking together, the MH produces emissions with a higher particle dose and more toxic compounds while causing only mild biological responses. This finding points to a significant mitigating effect of antioxidative compounds in MH wood smoke

Levels and drivers of urban black carbon and health risk assessment during pre- and COVID19 lockdown in Augsburg, Germany

This study aimed to evaluate the levels and phenomenology of equivalent black carbon (eBC) at the city center of Augsburg, Germany (01/2018 to 12/2020). Furthermore, the potential health risk of eBC based on equivalent numbers of passively smoked cigarettes (PSC) was also evaluated, with special emphasis on the impact caused by the COVID19 lockdown restriction measures. As it could be expected, peak concentrations of eBC were commonly recorded in morning (06:00-8:00 LT) and night (19:00-22:00 LT) in all seasons, coinciding with traffic rush hours and atmospheric stagnation. The variability of eBC was highly influenced by diurnal variations in traffic and meteorology (air temperature (T), mixing-layer height (MLH), wind speed (WS)) across days and seasons. Furthermore, a marked "weekend effect" was evidenced, with an average eBC decrease of ∼35% due to lower traffic flow. During the COVID19 lockdown period, an average ∼60% reduction of the traffic flow resulted in ∼30% eBC decrease, as the health risks of eBC exposure was markedly reduced during this period. The implementation of a multilinear regression analysis allowed to explain for 53% of the variability in measured eBC, indicating that the several factors (e.g., traffic and meteorology) may contribute simultaneously to this proportion. Overall, this study will provide valuable input to the policy makers to mitigate eBC pollutant and its adverse effect on environment and human health.The work is funded by National Natural Science Foundation of China (42101470), Support Project of High-level Teachers in Beijing Municipal Universities in the Period of 13th Five–year Plan (CIT&TCD201904037), the RI-URBANS project (Research Infrastructures Services Reinforcing Air Quality Monitoring Capacities in European Urban & Industrial Areas, European Union's Horizon 2020 research and innovation program, Green Deal, European Commission, contract 101036245), the dtec.bw -Digitalization and Technology Research Center of the Bundeswehr (project MORE), and Peiyang Future Scholar Scholarship (6120000246). We would like to thank to the Administration of Augsburg City for giving access to the traffic data (Tiefbauamt, Markus Furnier). We also would like to thank Prof. Dr. Stefan Emeis from Institute of Meteorology and Climate Research - Atmospheric Environmental Research (IMK-IFU) of Karlsruhe Institute of Technology for providing a ceilometer.Peer reviewe

Chemical Fingerprinting of Biomass Burning Organic Aerosols from Sugar Cane Combustion: Complementary Findings from Field and Laboratory Studies

Agricultural fires are a major source of biomass-burning organic aerosols (BBOAs) with impacts on health, the environment, and climate. In this study, globally relevant BBOA emissions from the combustion of sugar cane in both field and laboratory experiments were analyzed using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry. The derived chemical fingerprints of fresh emissions were evaluated using targeted and nontargeted evaluation approaches. The open-field sugar cane burning experiments revealed the high chemical complexity of combustion emissions, including compounds derived from the pyrolysis of (hemi)cellulose, lignin, and further biomass, such as pyridine and oxime derivatives, methoxyphenols, and methoxybenzenes, as well as triterpenoids. In comparison, laboratory experiments could only partially model the complexity of real combustion events. Our results showed high variability between the conducted field and laboratory experiments, which we, among others, discuss in terms of differences in combustion conditions, fuel composition, and atmospheric processing. We conclude that both field and laboratory studies have their merits and should be applied complementarily. While field studies under real-world conditions are essential to assess the general impact on air quality, climate, and environment, laboratory studies are better suited to investigate specific emissions of different biomass types under controlled conditions