Fant 9747 publikasjoner. Viser side 352 av 390:
2023
Uptake of organic contaminants from car tire microplastics in Arctic marine species
Car tire particles represent an important environmental challenge that is difficult to alleviate. The particles stem from abrasion during driving, so-called tire wear particles (TWPs), down-cycled end-oflife tire crumb rubber (CR) granulate that is used widely as low-cost infill on sports fields, or degradation products from discarded tires. The material contains a variety of additives and chemical residues from the manufacturing process, including metals, especially high concentrations of zinc, polycyclic aromatic hydrocarbons (PAHs), and benzothiazoles (Halsband et al., 2020), but also paraphenylenediaminesb (PPDs) and numerous other organic chemicals. In urbanized areas, TWPs arebemitted from vehicles, while CR is dispersed from artificial sports fields and other urban surfaces to the environment. This suggests that particulate and chemical runoff to coastal systems is likely and represents a route of exposure to marine organisms. In the Arctic, even small human settlements can represent local sources of TWPs and CR granulate emissions. Here, we summarize recent experimental studies examining the responses of different marine animals to tire rubber particle or leachate exposure, focusing on toxicity and the uptake kinetics of tire-related organic chemicals into organs and tissues. We present data for different ecological functional groups relevant to the Arctic, including copepods, shrimps, crabs, and fish, representing different body sizes, marine habitats, and feeding modes, and thus varying exposure scenarios. Our findings from GC-HRMS SIM chromatography demonstrate that several tire additives are taken up into tissues. Although the available data indicates many tire-derived organic chemicals do not seem to bioaccumulate, mapping of tire rubber particle and chemical distributions in Arctic coastal systems, dose-response toxicity testing and risk assessments of environmental concentrations are warranted, also with a view to potential trophic transfer within the Arctic marine food chain.
2023
2023
Antarctica and the Southern Ocean are important parts of the Earth system. The physical and biological properties here to a large degree control and shape other parts of the Earth through atmospheric, cryospheric and oceanic connections. The Troll Observing Network – TONe - is a new comprehensive infrastructure centered around the Norwegian Troll Research Station in Dronning Maud Land. It will be an important contribution to global research efforts in this part of Antarctica, closing data gaps in Antarctic environmental observations and providing key data required to respond to the fundamental societal challenges and uncertainties facing the world today. The Norwegian and international partner consortium in TONe is in the process to develop the state-of-the-art, multi-platform, multi-disciplinary observatory network for environmental observations, and a remotely piloted aerial system (RPAS) services to collect data for studying and monitoring the atmosphere, terrestrial and marine environment. The observatory network consists of 8 observatories: an integrated cloud observatory, an atmosphere composition observatory, an infrasound array, an ionospheric observatory, a seismic array, an ice-shelf observatory, a multidisciplinary open ocean moored observatory and a sea-bird observatory. The key aspect of TONe is to ensure wide and free access to the data from the observatories and the RPAS services to the entire national and international research community. TONe as a whole will be implemented and fully operational from 2027, while single parts of the infrastructure will be available before that.
2023
Finnfjord AS. Oppdaterte spredningsberegninger av utslipp til luft.
NILU har vurdert spredning av utslipp til luft fra Finnfjord AS sitt smelteverk ved Finnsnes. Bakgrunnen er oppdaterte krav fra Miljødirektoratet. Fokus i studien er på NOx, SO2 og støv/partikler. Det er utført lokale spredningsberegninger ved hjelp av modellen CONDEP. Regionale beregninger av konsentrasjoner og avsetning er utført med WRF-EMEP modellsystemet. En stor andel av forurensningen slippes ut fra tak. Dette kan gi turbulens og bygningsnedtrekk som igjen gir høye konsentrasjoner rett ved smelteverket og i umiddelbar nærhet. CONDEP-beregningene viser at for NO2 og støv/PM er norske grenseverdier overholdt. For SO2 kan overskridelse av grenseverdier oppstå opptil 500-600 m fra smelteverket. WRF-EMEP-beregningene viser liten påvirkning på regional skala. Av utslippene fra Finnfjord AS avsettes 16 % av nitrogen, 15 % av svovel og 12 % av PM innenfor det innerste gridet (105 x 105 km2). Det gis også anbefaling om målinger av SO2 og meteorologi for å tallfeste påvirkningen fra Finnfjord AS på omgivelsene.
NILU
2023
2023
Modelling the coupled mercury-halogen-ozone cycle in the central Arctic during spring
Near-surface mercury and ozone depletion events occur in the lowest part of the atmosphere during Arctic spring. Mercury depletion is the first step in a process that transforms long-lived elemental mercury to more reactive forms within the Arctic that are deposited to the cryosphere, ocean, and other surfaces, which can ultimately get integrated into the Arctic food web. Depletion of both mercury and ozone occur due to the presence of reactive halogen radicals that are released from snow, ice, and aerosols. In this work, we added a detailed description of the Arctic atmospheric mercury cycle to our recently published version of the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem 4.3.3) that includes Arctic bromine and chlorine chemistry and activation/recycling on snow and aerosols. The major advantage of our modelling approach is the online calculation of bromine concentrations and emission/recycling that is required to simulate the hourly and daily variability of Arctic mercury depletion. We used this model to study coupling between reactive cycling of mercury, ozone, and bromine during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) spring season in 2020 and evaluated results compared to land-based, ship-based, and remote sensing observations. The model predicts that elemental mercury oxidation is driven largely by bromine chemistry and that particulate mercury is the major form of oxidized mercury. The model predicts that the majority (74%) of oxidized mercury deposited to land-based snow is re-emitted to the atmosphere as gaseous elemental mercury, while a minor fraction (4%) of oxidized mercury that is deposited to sea ice is re-emitted during spring. Our work demonstrates that hourly differences in bromine/ozone chemistry in the atmosphere must be considered to capture the springtime Arctic mercury cycle, including its integration into the cryosphere and ocean.
2023
Marine mammals are considered sentinel species and may act as indicators of ocean health. Plastic residues are widely distributed in the oceans and are recognised as hazardous contaminants, and once ingested can cause several adverse effects on wildlife. This study aimed to identify and characterise plastic ingestion in the Guiana dolphins (Sotalia guianensis) from the Southwestern Tropical Atlantic by evaluating the stomach contents of stranded individuals through KOH digestion and identification of subsample of particles by LDIR Chemical Imaging System. Most of the individuals were contaminated, and the most common polymers identified were PU, PET and EVA. Microplastics were more prevalent than larger plastic particles (meso- and macroplastics). Smaller particles were detected during the rainy seasons. Moreover, there was a positive correlation between the stomach content mass and the number of microplastics, suggesting contamination through trophic transfer.
Elsevier
2023
2023
This paper examines the creation of fine resolution maps at 100 m x 100 m resolution using statistical downscaling for the area of Prague, as a case study. This Czech city was selected due to the fine resolution proxy data available for this city. The reference downscaling methodology used is the linear regression and the interpolation of its residuals by the area-to-point kriging. Next to this, several other methods of statistical downscaling have been also executed. The results of different downscaling methods have been compared mutually and against the data from the monitoring stations of Prague, separately for urban background and traffic areas.
The downscaled maps in 100 m x 100 m resolution have been constructed for the area of Prague for three pollutants, namely for NO2, PM10 and PM2.5. Several methods of the statistical downscaling have been compared mutually and against the data from the monitoring stations. In general, the best results are given by the linear regression and the interpolation of its residuals, either by the area-to-point kriging or the bilinear interpolation. In the maps, one can see overall realistic spatial patterns, the main roads in Prague are visible through higher air pollution levels. This is distinct especially for NO2, while for PM10 and PM2.5 the differences between road increments and urban background are smaller as would be expected. The results of the case study for Prague have proven the usefulness of the statistical downscaling for the air quality mapping, especially for NO2. In addition, the population exposure estimates based on the downscaled mapping results have been also calculated.
ETC/HE
2023
2023
2023
2023
2023