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New insights from an eight-year study on per- and polyfluoroalkyl substances in an urban terrestrial ecosystem

Heimstad, Eldbjørg Sofie; Nygård, Torgeir; Moe, Børge; Herzke, Dorte

Per- and polyfluoroalkyl substances (PFAS) were analysed in a high number of terrestrial samples of soil, earthworm, bird eggs and liver from red fox and brown rat in an urban area in Norway from 2013 to 2020. PFOS and the long chain PFCAs were the most dominating compounds in all samples, proving their ubiquitous distribution. Other less studied compounds such as 6:2 FTS were first and foremost detected in earthworm. 8:2 FTS was found in many samples of fieldfare egg, sparrowhawk egg and earthworm, where the eggs had highest concentrations. Highest concentrations for both 6:2 FTS and 8:2 FTS were detected at present and former industry areas. FOSA was detected in many samples of the species with highest concentrations in red fox liver and brown rat liver of 3.3 and 5.5 ng/g ww.

PFAS concentrations from the urban area were significantly higher than from background areas indicating that some of the species can be suitable as markers for PFAS emissions in an urban environment. Fieldfare eggs had surprisingly high concentrations of PFOS and PFCA concentrations from areas known to be or have been influenced by industry. Biota-soil-accumulation factor and magnification calculations indicate accumulation and magnification potential for several PFAS.

Earthworm and fieldfare egg had average concentrations above the Canadian and European thresholds in diet for avian wildlife and predators. For earthworms, 18 % of the samples exceeded the European threshold (33 ng/g ww) of PFOS in prey for predators, and for fieldfare eggs, 35 % of the samples were above the same threshold. None of the soil samples exceeded a proposed PNEC of PFOS for soil living organisms of 373 ng/g dw.

Elsevier

2024

Widespread Pesticide Distribution in the European Atmosphere Questions their Degradability in Air

Mayer, Ludovic; Degrendele, Celine; Senk, Petr; Kohoutek, Jiří; Přibylovác, Petra; Kukučka, Petr; Melymuk, Lisa; Durand, Amandine; Ravier, Sylvain; Alastuey, Andres; Baker, Alex R.; Baltensperger, Urs; Baumann-Stanzer, Kathrin; Biermann, Tobias; Bohlin-Nizzetto, Pernilla; Ceburnis, Darius; Conil, Sébastien; Couret, Cedric; Degorska, Anna; Diapouli, Evangelia; Eckhardt, Sabine; Eleftheriadis, Konstantinos; Forster, Grant L.; Freier, Korbinian; Gheusi, Francois; Gini, Maria; Hellén, Heidi; Henne, Stephan; Hermann, Hartmut; Šmejkalová, Adéla Holubová; Horrak, Urmas; Hüglin, Christoph; Junninen, Heikki; Kristensson, Adam; Langrene, Laurent; Levula, Janne; Lothon, Marie; Ludewig, Elke; Makkonen, Ulla; Matejovičová, Jana; Mihalopoulos, Nikolaos; Mináriková, Veronika; Moche, Wolfgang; Noe, Steffen M.; Perez, Noemi; Petäjä, Tuukka; Pont, Veronique; Poulain, Laurent; Quivet, Etienne; Ratz, Gabriela; Rehm, Till; Reimann, Stefan; Simmons, Ivan; Sonke, Jeroen E.; Sorribas, Mar; Spoor, Ronald; Swart, Daan P.J.; Vasilatou, Vasiliki; Wortham, Henri; Yela, Margarita; Zarmpas, Pavlos; Zellweger-Fäsi, Claudia; Tørseth, Kjetil; Laj, Paolo G.; Klanova, Jana; Lammel, Gerhard

Risk assessment of pesticide impacts on remote ecosystems makes use of model-estimated degradation in air. Recent studies suggest these degradation rates to be overestimated, questioning current pesticide regulation. Here, we investigated the concentrations of 76 pesticides in Europe at 29 rural, coastal, mountain, and polar sites during the agricultural application season. Overall, 58 pesticides were observed in the European atmosphere. Low spatial variation of 7 pesticides suggests continental-scale atmospheric dispersal. Based on concentrations in free tropospheric air and at Arctic sites, 22 pesticides were identified to be prone to long-range atmospheric transport, which included 15 substances approved for agricultural use in Europe and 7 banned ones. Comparison between concentrations at remote sites and those found at pesticide source areas suggests long atmospheric lifetimes of atrazine, cyprodinil, spiroxamine, tebuconazole, terbuthylazine, and thiacloprid. In general, our findings suggest that atmospheric transport and persistence of pesticides have been underestimated and that their risk assessment needs to be improved.

2024

Composition and sources of carbonaceous aerosol in the European Arctic at Zeppelin Observatory, Svalbard (2017 to 2020)

Yttri, Karl Espen; Bäcklund, Are; Conen, Franz; Eckhardt, Sabine; Evangeliou, Nikolaos; Fiebig, Markus; Kasper-Giebl, Anne; Gold, Avram; Gundersen, Hans; Myhre, Cathrine Lund; Platt, Stephen Matthew; Simpson, David; Surratt, Jason D.; Szidat, Sönke; Rauber, Martin; Tørseth, Kjetil; Ytre-Eide, Martin Album; Zhang, Zhenfa; Aas, Wenche

We analyzed long-term measurements of organic carbon, elemental carbon, and source-specific organic tracers from 2017 to 2020 to constrain carbonaceous aerosol sources in the rapidly changing Arctic. Additionally, we used absorption photometer (Aethalometer) measurements to constrain equivalent black carbon (eBC) from biomass burning and fossil fuel combustion, using positive matrix factorization (PMF).

Our analysis shows that organic tracers are essential for understanding Arctic carbonaceous aerosol sources. Throughout 2017 to 2020, levoglucosan exhibited bimodal seasonality, reflecting emissions from residential wood combustion (RWC) in the heating season (November to May) and from wildfires (WFs) in the non-heating season (June to October), demonstrating a pronounced interannual variability in the influence of WF. Biogenic secondary organic aerosol (BSOA) species (2-methyltetrols) from isoprene oxidation was only present in the non-heating season, peaking in July to August. Warm air masses from Siberia led to a substantial increase in 2-methyltetrols in 2019 and 2020 compared to 2017 to 2018. This highlights the need to investigate the contribution of local sources vs. long-range atmospheric transport (LRT), considering the temperature sensitivity of biogenic volatile organic compound emissions from Arctic vegetation. Tracers of primary biological aerosol particles (PBAPs), including various sugars and sugar alcohols, showed elevated levels in the non-heating season, although with different seasonal trends, whereas cellulose had no apparent seasonality. Most PBAP tracers and 2-methyltetrols peaked during influence of WF emissions, highlighting the importance of measuring a range of source-specific tracers to understand sources and dynamics of carbonaceous aerosol. The seasonality of carbonaceous aerosol was strongly influenced by LRT episodes, as background levels are extremely low. In the non-heating season, the organic aerosol peak was as influenced by LRT, as was elemental carbon during the Arctic haze period.

Source apportionment of carbonaceous aerosol by Latin hypercube sampling showed mixed contributions from RWC (46 %), fossil fuel (FF) sources (27 %), and BSOA (25 %) in the heating season. In contrast, the non-heating season was dominated by BSOA (56 %), with lower contributions from WF (26 %) and FF sources (15 %).

Source apportionment of eBC by PMF showed that FF combustion dominated eBC (70±2.7 %), whereas RWC (22±2.7 %) was more abundant than WF (8.0±2.9 %). Modeled BC concentrations from FLEXPART (FLEXible PARTicle dispersion model) attributed an almost equal share to FF sources (51±3.1 %) and to biomass burning. Both FLEXPART and the PMF analysis concluded that RWC is a more important source of (e)BC than WF. However, with a modeled RWC contribution of 30±4.1 % and WF of 19±2.8 %, FLEXPART suggests relatively higher contributions to eBC from these sources. Notably, the BB fraction of EC was twice as high as that of eBC, reflecting methodological differences between source apportionment by LHS and PMF. However, important conclusions drawn are unaffected, as both methods indicate the presence of RWC- and WF-sourced BC at Zeppelin, with a higher relative BB contribution during the non-heating season.

In summary, organic aerosol (281±106 ng m−3) constitutes a significant fraction of Arctic PM10, although surpassed by sea salt aerosol (682±46.9 ng m−3), mineral dust (613±368 ng m−3), and typically non-sea-salt sulfate SO (314±62.6 ng m−3), originating mainly from anthropogenic sources in winter and from natural sources in summer.

2024

Recommendations for reporting equivalent black carbon (eBC) mass concentrations based on long-term pan-European in-situ observations

Savadkoohi, Marjan; Pandolfi, Marco; Favez, Olivier; Putaud, Jean-Philippe; Eleftheriadis, Konstantinos; Fiebig, Markus; Hopke, Philip K.; Laj, Paolo G.; Wiedensohler, Alfred; Alados-Arboledas, Lucas; Bastian, Susanne; Chazeau, Benjamin; Maria, Alvaro Clemente; Colombi, Cristina; Costabile, Francesca; Green, David C.; Hueglin, Christoph; Liakakou, Eleni; Luoma, Krista; Listrani, Stefano; Mihalopoulos, Nikos; Marchand, Nicolas; Močnik, Griša; Niemi, Jarkko V; Ondráček, Jakub; Petit, Jean Eudes; Rattigan, Oliver V.; Reche, Cristina; Timonen, Hilkka; Titos, Gloria; Tremper, Anja H.; Vratolis, Stergios; Vodicka, Petr; Funes, Eduardo Yubero; Zíková, Naděžda; Harrison, Roy M.; Petäjä, Tuukka; Alastuey, Andrés; Querol, Xavier

A reliable determination of equivalent black carbon (eBC) mass concentrations derived from filter absorption photometers (FAPs) measurements depends on the appropriate quantification of the mass absorption cross-section (MAC) for converting the absorption coefficient (babs) to eBC. This study investigates the spatial–temporal variability of the MAC obtained from simultaneous elemental carbon (EC) and babs measurements performed at 22 sites. We compared different methodologies for retrieving eBC integrating different options for calculating MAC including: locally derived, median value calculated from 22 sites, and site-specific rolling MAC. The eBC concentrations that underwent correction using these methods were identified as LeBC (local MAC), MeBC (median MAC), and ReBC (Rolling MAC) respectively. Pronounced differences (up to more than 50 %) were observed between eBC as directly provided by FAPs (NeBC; Nominal instrumental MAC) and ReBC due to the differences observed between the experimental and nominal MAC values. The median MAC was 7.8 ± 3.4 m2 g-1 from 12 aethalometers at 880 nm, and 10.6 ± 4.7 m2 g-1 from 10 MAAPs at 637 nm. The experimental MAC showed significant site and seasonal dependencies, with heterogeneous patterns between summer and winter in different regions. In addition, long-term trend analysis revealed statistically significant (s.s.) decreasing trends in EC. Interestingly, we showed that the corresponding corrected eBC trends are not independent of the way eBC is calculated due to the variability of MAC. NeBC and EC decreasing trends were consistent at sites with no significant trend in experimental MAC. Conversely, where MAC showed s.s. trend, the NeBC and EC trends were not consistent while ReBC concentration followed the same pattern as EC. These results underscore the importance of accounting for MAC variations when deriving eBC measurements from FAPs and emphasize the necessity of incorporating EC observations to constrain the uncertainty associated with eBC.

Elsevier

2024

Hazard assessment of nanomaterials using in vitro toxicity assays: Guidance on potential assay interferences and mitigating actions to avoid biased results

El Yamani, Naouale; Rundén-Pran, Elise; Varet, Julia; Beus, Maja; Dusinska, Maria; Fessard, Valerie; Moschini, Elisa; Serchi, Tommaso; Cimpan, Mihaela Roxana; Lynch, Iseult; Vinković Vrček, ivana

The movement towards an animal-free testing approach for risk assessment represents a key paradigm shift in toxicology. Risk assessment of engineered and anthropogenic nanoscale materials (NM) is dependent on reliable hazard characterization, which requires validated test methods and models, and increasingly on mechanistic insights into the mode of action. The properties that make NMs so advantageous for a wide range of commercial and industrial applications also pose a challenge when it comes to safety testing under in vitro and in chemico experimental settings. Their large reactive surface area makes NMs prone to interactions with assay reagents, readout signals, or intermediate steps of many test assays, leading to the potential for biased results and data inconsistencies, collectively referred to as interferences. Therefore, methods and protocols developed and validated for conventional chemicals often require adaptation and checking for reliability in NMs' toxicity assessment. This review presents the collected scientific knowledge on NMs-induced interferences for the most common in vitro toxicity assays and methods related to cytotoxicity, oxidative stress and inflammatory response evaluation. Our analysis of existing scientific literature showed that the challenge of NMs-induced interference was not explicitly addressed in more than 90% of the papers published up to 2014 reporting the safety and toxicity of NMs. In later years, increasing number of studies tackled the interference challenge in toxicity testing of NMs, which initiated exhaustive work on standardization and validation of existing regulatory-relevant in vitro test protocols and guidelines. Due to the specificity of the different NMs and the range of ways they can potentially interfere with in vitro assays, interference and fit-for purpose controls should be included for each NM type and method applied, unless label-free assays are selected. Here, we provide a decision tree to guide researchers on how to design experiments to avoid interferences during in vitro testing by taking appropriate mitigation actions and how to include proper interference controls in their experimental design where complete avoidance is not possible. The application of this decision tree will improve the reliability, comparability and reusability of in vitro toxicity data on engineered NMs or ENMs, increasing the relevance of in silico hazard data for use in risk assessment and in science-based risk governance of NMs. The approach is applicable more broadly also, to advanced materials and to hazard assessment of anthropogenic nanoscale materials such as microplastic and tyre-wear particles.

Elsevier

2024

Aircraft-based mass balance estimate of methane emissions from offshore gas facilities in the southern North Sea

Pühl, Magdalena; Roiger, Anke; Fiehn, Alina; Gorchov Negron, Alan M.; Kort, Eric A.; Schwietzke, Stefan; Pisso, Ignacio; Foulds, Amy; Lee, James; France, James L.; Jones, Anna E.; Lowry, Dave; Fisher, Rebecca E.; Huang, Langwen; Shaw, Jacob; Bateson, Prudence; Andrews, Stephen; Young, Stuart; Dominutti, Pamela; Lachlan-Cope, Tom; Weiss, Alexandra; Allen, Grant

Atmospheric methane (CH4) concentrations have more than doubled since the beginning of the industrial age, making CH4 the second most important anthropogenic greenhouse gas after carbon dioxide (CO2). The oil and gas sector represents one of the major anthropogenic CH4 emitters as it is estimated to account for 22 % of global anthropogenic CH4 emissions. An airborne field campaign was conducted in April–May 2019 to study CH4 emissions from offshore gas facilities in the southern North Sea with the aim of deriving emission estimates using a top-down (measurement-led) approach. We present CH4 fluxes for six UK and five Dutch offshore platforms or platform complexes using the well-established mass balance flux method. We identify specific gas production emissions and emission processes (venting and fugitive or flaring and combustion) using observations of co-emitted ethane (C2H6) and CO2. We compare our top-down estimated fluxes with a ship-based top-down study in the Dutch sector and with bottom-up estimates from a globally gridded annual inventory, UK national annual point-source inventories, and operator-based reporting for individual Dutch facilities. In this study, we find that all the inventories, except for the operator-based facility-level reporting, underestimate measured emissions, with the largest discrepancy observed with the globally gridded inventory. Individual facility reporting, as available for Dutch sites for the specific survey date, shows better agreement with our measurement-based estimates. For all the sampled Dutch installations together, we find that our estimated flux of (122.9 ± 36.8) kg h−1 deviates by a factor of 0.64 (0.33–12) from reported values (192.8 kg h−1). Comparisons with aircraft observations in two other offshore regions (the Norwegian Sea and the Gulf of Mexico) show that measured, absolute facility-level emission rates agree with the general distribution found in other offshore basins despite different production types (oil, gas) and gas production rates, which vary by 2 orders of magnitude. Therefore, mitigation is warranted equally across geographies.

2024

Air-soil cycling of oxygenated, nitrated and parent polycyclic aromatic hydrocarbons in source and receptor areas

Mwangi, John K.; Degrendele, Celine; Bandowe, Benjamin A. M.; Bohlin-Nizzetto, Pernilla; Halse, Anne Karine; Šmejkalová, Adela Holubová; Kim, Jun-Tae; Kukučka, Petr; Martiník, Jakub; Nežiková, Barbora Palátová; Přibylová, Petra; Prokeš, Roman; Sáňka, Milan; Tannous, Mariam; Vinkler, Jakub; Lammel, Gerhard

Elsevier

2024

Estimation of the atmospheric hydroxyl radical oxidative capacity using multiple hydrofluorocarbons (HFCs)

Thompson, Rona Louise; Montzka, Stephen A.; Vollmer, Martin K.; Arduini, Jgor; Crotwell, Molly; Krummel, Paul B.; Lunder, Chris Rene; Mühle, Jens; O'doherty, Simon; Prinn, Ronald G.; Reimann, Stefan; Vimont, Isaac; Wang, Hsiang; Weiss, Ray F.; Young, Dickon

2024

Trends in Air Pollution in Europe, 2000–2019

Aas, Wenche; Fagerli, Hilde; Alastuey, Andres; Cavalli, Fabrizia; Degorska, Anna; Feigenspan, Stefan; Brenna, Hans; Gliss, Jonas; Heinesen, Daniel; Hueglin, Christoph; Holubová, Adela; Jaffrezo, Jean-Luc; Mortier, Augustin; Murovec, Marijana; Putaud, Jean-Philippe; Rüdige, Julian; Simpson, David; Solberg, Sverre; Tsyro, Svetlana; Tørseth, Kjetil; Yttri, Karl Espen

This paper encompasses an assessment of air pollution trends in rural environments in Europe over the 2000–2019 period, benefiting from extensive long-term observational data from the EMEP monitoring network and EMEP MSC-W model computations. The trends in pollutant concentrations align with the decreasing emission patterns observed throughout Europe. Annual average concentrations of sulfur dioxide, particulate sulfate, and sulfur wet deposition have shown consistent declines of 3-4% annually since 2000. Similarly, oxidized nitrogen species have markedly decreased across Europe, with an annual reduction of 1.5-2% in nitrogen dioxide concentrations, total nitrate in the air, and oxidized nitrogen deposition. Notably, emission reductions and model predictions appear to slightly surpass the observed declines in sulfur and oxidized nitrogen, indicating a potential overestimation of reported emission reductions. Ammonia emissions have decreased less compared to other pollutants since 2000. Significant reductions in particulate ammonium have however, been achieved due to the impact of reductions in SOx and NOx emissions. For ground level ozone, both the observed and modelled peak levels in summer show declining trends, although the observed decline is smaller than modelled. There have been substantial annual reductions of 1.8% and 2.4% in the concentrations of PM10 and PM2.5, respectively. Elemental carbon has seen a reduction of approximately 4.5% per year since 2000. A similar reduction for organic carbon is only seen in winter when primary anthropogenic sources dominate. The observed improvements in European air quality emphasize the importance of comprehensive legislations to mitigate emissions.

2024

Optical and Microphysical Properties of the Aerosols during a Rare Event of Biomass-Burning Mixed with Polluted Dust

Gidarakou, Marilena; Papayannis, Alexandros; Kokkalis, Panagiotis; Evangeliou, Nikolaos; Vratolis, Stergios; Remoundaki, Emmanouella; Zwaaftink, Christine Groot; Eckhardt, Sabine; Veselovskii, Igor; Mylonaki, Maria; Argyrouli, Athina; Eleftheriadis, Konstantinos; Solomos, Stavros; Gini, Maria

A rare event of mixed biomass-burning and polluted dust aerosols was observed over Athens, Greece (37.9° N, 23.6° E), during 21–26 May 2014. This event was studied using a synergy of a 6-wavelength elastic-Raman-depolarization lidar measurements, a CIMEL sun photometer, and in situ instrumentation. The FLEXPART dispersion model was used to identify the aerosol sources and quantify the contribution of dust and black carbon particles to the mass concentration. The identified air masses were found to originate from Kazakhstan and Saharan deserts, under a rare atmospheric pressure system. The lidar ratio (LR) values retrieved from the Raman lidar ranged within 25–89 sr (355 nm) and 35–70 sr (532 nm). The particle linear depolarization ratio (δaer) ranged from 7 to 28% (532 nm), indicating mixing of dust with biomass-burning particles. The aerosol optical depth (AOD) values derived from the lidar ranged from 0.09–0.43 (355 nm) to 0.07–0.25 (532 nm). An inversion algorithm was used to derive the mean aerosol microphysical properties (mean effective radius (reff), single scattering albedo (SSA), and mean complex refractive index (m)) inside selected atmospheric layers. We found that reff was 0.12–0.51 (±0.04) µm, SSA was 0.94–0.98 (±0.19) (at 532 nm), while m ranged between 1.39 (±0.05) + 0.002 (±0.001)i and 1.63 (±0.05) + 0.008 (±0.004)i. The polarization lidar photometer networking (POLIPHON) algorithm was used to estimate the vertical profile of the mass concentration for the dust and non-dust components. A mean mass concentration of 15 ± 5 μg m−3 and 80 ± 29 μg m−3 for smoke and dust was estimated for selected days, respectively. Finally, the retrieved aerosol microphysical properties were compared with column-integrated sun photometer CIMEL data with good agreement

MDPI

2024

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