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Mercury in air and soil on an urban-rural transect in East Africa

Nipen, Maja; Jørgensen, Susanne Jøntvedt; Bohlin-Nizzetto, Pernilla; Borgå, Katrine; Breivik, Knut; Mmochi, Aviti J; Mwakalapa, Eliezer; Quant, M. Isabel; Schlabach, Martin; Vogt, Rolf David; Wania, Frank

There are large knowledge gaps concerning concentrations, sources, emissions, and spatial trends of mercury (Hg) in the atmosphere in developing regions of the Southern Hemisphere, particularly in urban areas. Filling these gaps is a prerequisite for assessing the effectiveness of international regulation and for enabling a better understanding of the global transport of Hg in the environment. Here we use a passive sampling technique to study the spatial distribution of gaseous elemental Hg (Hg(0), GEM) and assess emission sources in and around Dar es Salaam, Tanzania's largest city. Included in the study were the city's main municipal waste dumpsite and an e-waste processing facility as potential sources of GEM. To complement the GEM data and for a better overview of the Hg contamination status of Dar es Salaam, soil samples were collected from the same locations where passive air samplers were deployed and analysed for total Hg. Overall, GEM concentrations ranged between <0.86 and 5.34 ng m−3, indicating significant local sources within the urban area. The municipal waste dumpsite and e-waste site had GEM concentrations elevated above the background, at 2.41 and 1.77 ng m−3, respectively. Hg concentrations in soil in the region (range 0.0067 to 0.098 mg kg−1) were low compared to those of other urban areas and were not correlated with atmospheric GEM concentrations. This study demonstrates that GEM is a significant environmental issue in the urban region of Dar es Salaam. Further studies from urban areas in the Global South are needed to better identify sources of GEM.

Royal Society of Chemistry

2022

Potential environmental impact of bromoform from Asparagopsis farming in Australia

Jia, Yue; Quack, Birgit; Kinley, Robert D.; Pisso, Ignacio; Tegtmeier, Susann

To mitigate the rumen enteric methane (CH4) produced by ruminant livestock, Asparagopsis taxiformis is proposed as an additive to ruminant feed. During the cultivation of Asparagopsis taxiformis in the sea or in terrestrially based systems, this macroalgae, like most seaweeds and phytoplankton, produces a large amount of bromoform (CHBr3), which contributes to ozone depletion once released into the atmosphere. In this study, we focus on the impact of CHBr3 on the stratospheric ozone layer resulting from potential emissions from proposed Asparagopsis cultivation in Australia. The impact is assessed by weighting the emissions of CHBr3 with its ozone depletion potential (ODP), which is traditionally defined for long-lived halocarbons but has also been applied to very short-lived substances (VSLSs). An annual yield of ∼3.5 × 104 Mg dry weight is required to meet the needs of 50 % of the beef feedlot and dairy cattle in Australia. Our study shows that the intensity and impact of CHBr3 emissions vary, depending on location and cultivation scenarios. Of the proposed locations, tropical farms near the Darwin region are associated with the largest CHBr3 ODP values. However, farming of Asparagopsis using either ocean or terrestrial cultivation systems at any of the proposed locations does not have the potential to significantly impact the ozone layer. Even if all Asparagopsis farming were performed in Darwin, the CHBr3 emitted into the atmosphere would amount to less than 0.02 % of the global ODP-weighted emissions. The impact of remaining farming scenarios is also relatively small even if the intended annual yield in Darwin is scaled by a factor of 30 to meet the global requirements, which will increase the global ODP-weighted emissions up to ∼0.5 %.

2022

Monitoring of the atmospheric ozone layer and natural ultraviolet radiation. Annual report 2021.

Svendby, Tove Marit; Hansen, Georg H.; Bernet, Leonie; Bäcklund, Are; Nilsen, Anne-Cathrine; Schulze, Dorothea; Johnsen, Bjørn

This report summarizes the results from the Norwegian monitoring programme on stratospheric ozone and UV radiation measurements. The ozone layer has been measured at three locations since 1979: In Oslo/Kjeller, Tromsø/Andøya and Ny-Ålesund. The UV-measurements started in 1995. The results show that there was a significant decrease in stratospheric ozone above Norway between 1979 and 1997. After that, the ozone layer stabilized at a level ~2% below pre-1980 level. The year 2021 was characterized by low total ozone values in June and July, whereas “normal” ozone values were measured during winter and spring.

NILU

2022

A pooled analysis of molecular epidemiological studies on modulation of DNA repair by host factors

Opattová, Alena; Langie, Sabine A.S.; Milic, Mirta; Collins, Andrew Richard; Brevik, Asgeir; Dusinska, Maria; Coskun, Erdem; Gaivao, Isabel; Kadioglu, Ela; Laffon, Blanca; Marcos, Ricard; Pastor, Susana; Slyskova, Jana; Smolkova, Bozena ; Szilagyi, Zsofia; Valdiglesias, Vanessa; Vodicka, Pavel; Volkovova, Katarina ; Godschalk, Roger W.L.

Levels of DNA damage represent the dynamics between damage formation and removal. Therefore, to better interpret human biomonitoring studies with DNA damage endpoints, an individual’s ability to recognize and properly remove DNA damage should be characterized. Relatively few studies have included DNA repair as a biomarker and therefore, assembling and analyzing a pooled database of studies with data on base excision repair (BER) was one of the goals of hCOMET (EU-COST CA15132). A group of approximately 1911 individuals, was gathered from 8 laboratories which run population studies with the comet-based in vitro DNA repair assay. BER incision activity data were normalized and subsequently correlated with various host factors. BER was found to be significantly higher in women. Although it is generally accepted that age is inversely related to DNA repair, no overall effect of age was found, but sex differences were most pronounced in the oldest quartile (>61 years). No effect of smoking or occupational exposures was found. A body mass index (BMI) above 25 kg/m2 was related to higher levels of BER. However, when BMI exceeded 35 kg/m2, repair incision activity was significantly lower. Finally, higher BER incision activity was related to lower levels of DNA damage detected by the comet assay in combination with formamidopyrimidine DNA glycosylase (Fpg), which is in line with the fact that oxidatively damaged DNA is repaired by BER. These data indicate that BER plays a role in modulating the steady-state level of DNA damage that is detected in molecular epidemiological studies and should therefore be considered as a parallel endpoint in future studies.

2022

RI-URBANS Data management​

Myhre, Cathrine Lund; Fiebig, Markus; Rud, Richard Olav; Thouret, Valérie; Boulanger, Damien

2022

A multi-pollutant and multi-sectorial approach to screening the consistency of emission inventories

Thunis, Philippe; Clappier, Alain; Pisoni, Enrico; Bessagnet, Bertrand; Kuenen, Jeroen; Guevara, Marc; Lopez-Aparicio, Susana

Some studies show that significant uncertainties affect emission inventories, which may impeach conclusions based on air-quality model results. These uncertainties result from the need to compile a wide variety of information to estimate an emission inventory. In this work, we propose and discuss a screening method to compare two emission inventories, with the overall goal of improving the quality of emission inventories by feeding back the results of the screening to inventory compilers who can check the inconsistencies found and, where applicable, resolve errors. The method targets three different aspects: (1) the total emissions assigned to a series of large geographical areas, countries in our application; (2) the way these country total emissions are shared in terms of sector of activity; and (3) the way inventories spatially distribute emissions from countries to smaller areas, cities in our application. The first step of the screening approach consists of sorting the data and keeping only emission contributions that are relevant enough. In a second step, the method identifies, among those significant differences, the most important ones that provide evidence of methodological divergence and/or errors that can be found and resolved in at least one of the inventories. The approach has been used to compare two versions of the CAMS-REG European-scale inventory over 150 cities in Europe for selected activity sectors. Among the 4500 screened pollutant sectors, about 450 were kept as relevant, among which 46 showed inconsistencies. The analysis indicated that these inconsistencies arose almost equally from large-scale reporting and spatial distribution differences. They mostly affect SO2 and PM coarse emissions from the industrial and residential sectors. The screening approach is general and can be used for other types of applications related to emission inventories.

2022

Hazard identification of nanomaterials: In silico unraveling of descriptors for cytotoxicity and genotoxicity

El Yamani, Naouale; Mariussen, Espen; Gromelski, Maciej; Wyrzykowska, Ewelina; Grabarek, Dawid; Puzyn, Tomasz; Tanasescu, Speranta; Dusinska, Maria; Rundén-Pran, Elise

Hazard identification and safety assessment of the huge variety of nanomaterials (NMs), calls for robust and validated toxicity screening tests in combination with cheminformatics approaches to identify factors that can drive toxicity. Cytotoxicity and genotoxicity of seventeen JRC repository NMs, derived from titanium dioxide, zinc oxide, silver and silica, were tested in vitro using human lung alveolar epithelial cells A549. Cytotoxicity was assessed with the AlamarBlue (AB) and colony forming efficiency (CFE) assays, and genotoxicity by the enzyme-linked version of the comet assay. Nanoparticle tracking analysis (NTA) was used to measure size of the NMs in stock and in cell culture medium at different time points. Categorization and ranking of cytotoxic and genotoxic potential were performed (EU-NanoREG2 project approach). Descriptors for prediction of NMs toxicity were identified by quantitative structure-activity relationship (QSAR) analysis. Our results showed that ZnO NMs (NM-110 and NM-111), and Ag NMs (NM-300K and NM-302) were cytotoxic, while the TiO2 and SiO2 NMs were non-cytotoxic. Regarding genotoxicity, TiO2 NM-100, ZnO NM-110, SiO2 NM-203 and Ag NM-300K were categorized as positive. Cheminformatics modeling identified electron properties and overall chemical reactivity as important descriptors for cytotoxic potential, HOMO-LUMO energy parameter, ionization potential, pristine size for the NMs´ genotoxic potential, and presence of surface coating as descriptor for induction of DNA oxidized base lesions.

Elsevier

2022

Six-week inhalation of lead oxide nanoparticles in mice affects antioxidant defense, immune response, kidneys, intestine and bones

Tulinska, Jana; Krivosikova, Zora; Liskova, Aurelia; Mikusova, Miroslava Lehotska; Masanova, Vlasta; Rollerova, Eva; Stefikova, Kornelia; Wsolova, Ladislava; Bábelová, Andrea; Tothova, Lubomira; Busova, Milena; Babickova, Janka; Uhnakova, Iveta; Alacova, Radka; Dusinska, Maria; Horvathova, Mira; Szabova, Michaela; Vecera, Zbynek; Mikuska, Pavel; Coufalik, Pavel; Krumal, Kamil; Alexa, Lukas; Piler, Pavel; Thon, Vojtech; Docekal, Bohumil

Royal Society of Chemistry

2022

Screening of Chlorinated Paraffins, Dechloranes and UV-filters in Nordic Countries

Schlabach, Martin; Borgen, Anders; Bæk, Kine; Kringstad, Alfhild

In 2019, the Nordic screening group decided to perform a Nordic screening on chlorinated paraffins, dechloranes and UV-filters. These compounds are used in a wide range of applications. They all have long range transport characteristics and can potentially be regulated under the Stockholm POP convention. However, there are still huge data gaps, which need to be addressed in order to fulfill regulation requests. Several topics and questions were in focus for more measurements and a deeper understanding: (1) importance of long-range atmospheric transport and deposition, (2) differences/similarities in terrestrial versus marine food chains, and (3) variations between the Nordic countries and between urban and remote areas. Based on these priorities, availability of samples, and other practical reasons, samples from different Nordic countries, different environments, and both urban and remote places were selected. This study includes analysis of the compounds in air, marine and freshwater fish and marine mammals and bird eggs, but as the chlorinated paraffins also have been found to accumulate in the terrestrial food web, terrestrial mammals and bird eggs were included as well. Additionally, samples of pine needles were analysed both to look at the possibility for long range transport and to investigate it as a possible source of chlorinated paraffins for the terrestrial mammals.

Nordic Council of Ministers

2022

Beregning av korrosjonsklasse fra miljøparametere i Fitjar. Lokasjon (59°56'11.5"N 5°19'58.4"Ø).

Grøntoft, Terje

Korrosjonsklasse ble beregnet på lokasjon (59°56'11.5"N 5°19'58.4"Ø) i Fitjar, Vestland, Norge, fra årsgjennomsnitt for miljøparametere etter ISO 9223 og ISO 12944-2. Det ble funnet at korrosjonsklassen med høy sannsynlighet er C3 og at dette i hovedsak er bestemt av våt-tiden på omtrent 4500 timer/år, som gjennomsnitt i perioden 2007-2022. Dette er godt innenfor grensene for C3 når saltavsetningen er

NILU

2022

Tiltaksutredning for lokal luftkvalitet i Levanger. Del 1: Kartlegging.

Weydahl, Torleif; Teigland, Even Kristian

Tiltaksutredningen for lokal luftkvalitet i Levanger, del 1 Kartlegging, skal gjøre rede for forurensningssituasjonen og mulige tiltak for å redusere nivået av luftforurensning innenfor kravene i forurensningsforskriften. Tiltaksutredningen omfatter en kartlegging med utslipps- og spredningsberegninger for alle relevante kilder til PM10 og PM2,5 i 2017 og 2019. I tillegg er det utført målinger av disse komponentene gjennom hele 2021 ved en målestasjon (Kirkegata) i Levanger sentrum. Basert på resultatene fra kartleggingen, er det foreslått en handlingsplan med fire hovedpunkter som kan bidra til å redusere forurensningsnivåene i Levanger.

NILU

2022

Do cytotoxicity and cell death cause false positive results in the in vitro comet assay?

Azqueta, Amaya ; Stopper, Helga; Zegura, Bojana; Dusinska, Maria; Møller, Peter

The comet assay is used to measure DNA damage induced by chemical and physical agents. High concentrations of test agents may cause cytotoxicity or cell death, which may give rise to false positive results in the comet assay. Systematic studies on genotoxins and cytotoxins (i.e. non-genotoxic poisons) have attempted to establish a threshold of cytotoxicity or cell death by which DNA damage results measured by the comet assay could be regarded as a false positive result. Thresholds of cytotoxicity/cell death range from 20% to 50% in various publications. Curiously, a survey of the latest literature on comet assay results from cell culture studies suggests that one-third of publications did not assess cytotoxicity or cell death. We recommend that it should be mandatory to include results from at least one type of assay on cytotoxicity, cell death or cell proliferation in publications on comet assay results. A combination of cytotoxicity (or cell death) and proliferation (or colony forming efficiency assay) is preferable in actively proliferating cells because it covers more mechanisms of action. Applying a general threshold of cytotoxicity/cell death to all types of agents may not be applicable; however, 25% compared to the concurrent negative control seems to be a good starting value to avoid false positive comet assay results. Further research is needed to establish a threshold value to distinguish between true and potentially false positive genotoxic effects detected by the comet assay.

2022

Elucidating the present-day chemical composition, seasonality and source regions of climate-relevant aerosols across the Arctic land surface

Moschos, Vaios; Schmale, Julia; Aas, Wenche; Becagli, Silvia; Calzolai, Giulia; Eleftheriadis, Konstantinos; Moffett, Claire E.; Schnelle-Kreis, Jürgen; Severi, Mirko; Sharma, Sangeeta; Skov, Henrik; Vestenius, Mika; Zhang, Wendy; Hakola, Hannele; Hellén, Heidi; Huang, Lin; Jaffrezo, Jean-Luc; Massling, Andreas; Nøjgaard, Jacob Klenø; Petäjä, Tuukka; Popovicheva, Olga; Sheesley, Rebecca J.; Traversi, Rita; Yttri, Karl Espen; Prévôt, André S. H.; Baltensperger, Urs; El Haddad, Imad

2022

Tomographic 3D reconstructions of artificial releases of SO2 in the atmospheric boundary layer

Pisso, Ignacio; Cassiani, Massimo; Stebel, Kerstin; Kylling, Arve; Dinger, Anna Solvejg; Ardeshiri, Hamidreza; Park, Soon-Young; Schmidbauer, Norbert; Stohl, Andreas

2022

Atmospheric composition in the European Arctic and 30 years of the Zeppelin Observatory, Ny-Ålesund

Platt, Stephen Matthew; Hov, Øystein; Berg, Torunn; Breivik, Knut; Eckhardt, Sabine; Eleftheriadis, Konstantinos; Evangeliou, Nikolaos; Fiebig, Markus; Fisher, Rebecca; Hansen, Georg Heinrich; Hansson, Hans-Christen; Heintzenberg, Jost; Hermansen, Ove; Heslin-Rees, Dominic; Holmén, Kim; Hudson, Stephen; Kallenborn, Roland; Krejci, Radovan; Krognes, Terje; Larssen, Steinar; Lowry, David; Myhre, Cathrine Lund; Lunder, Chris Rene; Nisbet, Euan; Bohlin-Nizzetto, Pernilla; Park, Ki-Tae; Pedersen, Christina Alsvik; Pfaffhuber, Katrine Aspmo; Röckmann, Thomas; Schmidbauer, Norbert; Solberg, Sverre; Stohl, Andreas; Ström, Johan; Svendby, Tove Marit; Tunved, Peter; Tørnkvist, Kjersti Karlsen; van der Veen, Carina; Vratolis, Stergios; Jun Yoon, Young; Yttri, Karl Espen; Zieger, Paul; Aas, Wenche; Tørseth, Kjetil

The Zeppelin Observatory (78.90∘ N, 11.88∘ E) is located on Zeppelin Mountain at 472 m a.s.l. on Spitsbergen, the largest island of the Svalbard archipelago. Established in 1989, the observatory is part of Ny-Ålesund Research Station and an important atmospheric measurement site, one of only a few in the high Arctic, and a part of several European and global monitoring programmes and research infrastructures, notably the European Monitoring and Evaluation Programme (EMEP); the Arctic Monitoring and Assessment Programme (AMAP); the Global Atmosphere Watch (GAW); the Aerosol, Clouds and Trace Gases Research Infrastructure (ACTRIS); the Advanced Global Atmospheric Gases Experiment (AGAGE) network; and the Integrated Carbon Observation System (ICOS). The observatory is jointly operated by the Norwegian Polar Institute (NPI), Stockholm University, and the Norwegian Institute for Air Research (NILU). Here we detail the establishment of the Zeppelin Observatory including historical measurements of atmospheric composition in the European Arctic leading to its construction. We present a history of the measurements at the observatory and review the current state of the European Arctic atmosphere, including results from trends in greenhouse gases, chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), other traces gases, persistent organic pollutants (POPs) and heavy metals, aerosols and Arctic haze, and atmospheric transport phenomena, and provide an outline of future research directions.

2022

The Emissions Fractions Approach to Assessing the Long-Range Transport Potential of Organic Chemicals

Breivik, Knut; McLachlan, Michael S.; Wania, Frank

The assessment of long-range transport potential (LRTP) is enshrined in several frameworks for chemical regulation such as the Stockholm Convention. Screening for LRTP is commonly done with the OECD Pov and LRTP Screening Tool employing two metrics, characteristic travel distance (CTD) and transfer efficiency (TE). Here we introduce a set of three alternative metrics and implement them in the Tool’s model. Each metric is expressed as a fraction of the emissions in a source region. The three metrics quantify the extent to which the chemical (i) reaches a remote region (dispersion, ϕ1), (ii) is transferred to surface media in the remote region (transfer, ϕ2), and (iii) accumulates in these surface media (accumulation, ϕ3). In contrast to CTD and TE, the emissions fractions metrics can integrate transport via water and air, enabling comprehensive LRTP assessment. Furthermore, since there is a coherent relationship between the three metrics, the new approach provides quantitative mechanistic insight into different phenomena determining LRTP. Finally, the accumulation metric, ϕ3, allows assessment of LRTP in the context of the Stockholm Convention, where the ability of a chemical to elicit adverse effects in surface media is decisive. We conclude that the emission fractions approach has the potential to reduce the risk of false positives/negatives in LRTP assessments.

2022

New Environmental Monitoring Program; Microplastics in Norwegian Coastal Areas, Rivers, Lakes and Air (Mikronor)

Bråte, Inger Lise Nerland; Hurley, Rachel; Hultman, Maria Thérése; Rødland, Elisabeth Strandbråten; Buenaventura, Nina Tuscano; Singdahl-Larsen, Cecilie; van Bavel, Bert; Herzke, Dorte; Lusher, Amy

2022

First documentation of plastic ingestion in the arctic glaucous gull (Larus hyperboreus)

Benjaminsen, Stine Charlotte; Bourgeon, Sophie; Herzke, Dorte; Ask, Amalie; Collard, France; Gabrielsen, Geir Wing

Arctic wildlife is facing multiple stressors, including increasing plastic pollution. Seabirds are intrinsic to marine ecosystems, but most seabird populations are declining. We lack knowledge on plastic ingestion in many arctic seabird species, and there is an urgent need for more information to enable risk assessment and monitoring. Our study aimed to investigate the occurrence of plastics in glaucous gulls (Larus hyperboreus) breeding on Svalbard. The glaucous gull is a sentinel species for the health of the arctic marine ecosystem, but there have been no studies investigating plastic occurrence in this species since 1994. As a surface feeder and generalist living in an area with high human activity on Svalbard, we expected to find plastic in its stomach. We investigated for plastic >1 mm and documented plastic ingestion for the first time in glaucous gulls, with a frequency of occurrence of 14.3% (n = 21). The plastics were all identified as user plastics and consisted of polypropylene (PP) and polystyrene (PS). Our study provides new quantitative and qualitative data on plastic burden and polymer type reported in a standardized manner establishing a reference point for future research and monitoring of arctic gulls on national and international levels.

Elsevier

2022

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