Found 10000 publications. Showing page 362 of 400:
2023
2023
There is considerable interest in identifying chemicals which have the potential to undergo long-range environmental transport (LRTP), accumulate in remote regions, and represent a possible risk to environmental and human health. In this report, we have screened a list of 1,000 organic chemicals, as well as selected brominated dioxins and furans (PBDD/Fs), for their potential to be dispersed, transferred to, and accumulated in remote regions. This screening was carried out applying a new set of LRTP metrics, collectively referred to as the emissions fractions approach (EFA), as implemented in a modified version of the OECD POV and LRTP (long-range transport potential) Screening Tool (The Tool).
NILU
2023
2023
2023
2023
Safety-by-design and engineered nanomaterials: the need to move from theory to practice
As the governance of engineered nanomaterials (ENMs) evolves, innovations in the prevention, mitigation, management, and transfer of risk shape discussion of how nanotechnology may mature and reach various marketplaces. Safety-by-Design (SbD) is one leading concept that, while equally philosophy as well as risk-based practice, can uniquely help address lingering uncertainties and concerns stemming from regulatory evaluation of ENM risk across worker, consumer, and environmental safety. This paper provides a discussion on the SbD concept across different disciplines aiming to identify different approaches and needs to meet regulatory requirements—ultimately, we argue that SbD is evolving both to meet the needs and discourse of various disciplines, and to apply within differing marketplaces and national regulatory structures. Understanding how SbD has evolved within ENM can yield a more practical application and development of SbD, and help guide or unify national and international ENM governance around a core set of safety-driven principles.
2023
Måling av maursyre og eddiksyre i to oppbevaringsbokser ved Munchmuseet i Oslo
Målinger av maursyre (HCOOH), eddiksyre (CH3COOH) og flyktige organiske forbindelser (VOC) ble gjort i to oppbevaringsbokser ved Munchmuseet i Oslo. Noe forhøyede konsentrasjoner av maursyre, eddiksyre og totale flyktige organiske forbindelser (TVOC) ble målt i boksene, men konsentrasjonene er like fullt lave sammenlignet med vurderte risikonivåer for kulturav-materialer.
NILU
2023
2023
Fine-resolution spatio-temporal maps of near-surface urban air temperature (Ta) provide crucial data inputs for sustainable urban decision-making, personal heat exposure, and climate-relevant epidemiological studies. The recent availability of IoT weather station data allows for high-resolution urban Ta mapping using approaches such as interpolation techniques or machine learning (ML). This study is aimed at executing these approaches and traditional numerical modeling within a practical and operational framework and evaluate their practicality and efficiency in cases where data availability, computational constraints, or specialized expertise pose challenges. We employ Netatmo crowd-sourced weather station data and three geospatial mapping approaches: (1) Ordinary Kriging, (2) statistical ML model (using predictors primarily derived from Earth Observation Data), and (3) weather research and forecasting model (WRF) to predict/map daily Ta at nearly 1-km spatial resolution in Warsaw (Poland) for June–September and compare the predictions against observations from 5 meteorological reference stations. The results reveal that ML can serve as a viable alternative approach to traditional kriging and numerical simulation, characterized by reduced complexity and higher computational speeds within the domain of urban meteorological studies (overall RMSE = 1.06 °C and R2 = 0.94, compared to ground-based meteorological stations). The results have implications for identifying the urban regions vulnerable to overheating and evidence-based urban management in response to climate change. Due to the open-sourced nature of the applied predictors and input parsimony, the ML method can be easily replicated for other EU cities.
2023
2023
A rise in HFC-23 emissions from eastern Asia since 2015
Trifluoromethane (CHF3, HFC-23), one of the most potent greenhouse gases among hydrofluorocarbons (HFCs), is mainly emitted to the atmosphere as a by-product in the production of the ozone-depleting legacy refrigerant and chemical feedstock chlorodifluoromethane (CHClF2, HCFC-22). A recent study on atmospheric observation-based global HFC-23 emissions (top-down estimates) showed significant discrepancies over 2014–2017 between the increase in the observation-derived emissions and the 87 % emission reduction expected from capture and destruction processes of HFC-23 at HCFC-22 production facilities implemented by national phase-out plans (bottom-up emission estimates) (Stanley et al., 2020). However, the actual regions responsible for the increased emissions were not identified. Here, we estimate the regional top-down emissions of HFC-23 for eastern Asia based on in situ measurements at Gosan, South Korea, and show that the HFC-23 emissions from eastern China have increased from 5.0±0.4 Gg yr−1 in 2008 to 9.5±1.0 Gg yr−1 in 2019. The continuous rise since 2015 was contrary to the large emissions reduction reported under the Chinese hydrochlorofluorocarbons production phase-out management plan (HPPMP). The cumulative difference between top-down and bottom-up estimates for 2015–2019 in eastern China was Gg, which accounts for 47±11 % of the global mismatch. Our analysis based on HCFC-22 production information suggests the HFC-23 emissions rise in eastern China is more likely associated with known HCFC-22 production facilities rather than the existence of unreported, unknown HCFC-22 production, and thus observed discrepancies between top-down and bottom-up emissions could be attributed to unsuccessful factory-level HFC-23 abatement and inaccurate quantification of emission reductions.
2023
The present study examined how climate changes may impact the concentrations of lipophilic organochlorines (OCs) in the blood of fasting High Arctic common eiders (Somateria mollissima) during incubation. Polychlorinated biphenyls (PCBs), 1-dichloro-2,2-bis (p-chlorophenyl) ethylene (p,p′-DDE), hexachlorobenzene (HCB) and four chlordane compounds (oxychlordane, trans-chlordane and trans- and cis-nonachlor) were measured in females at chick hatching (n = 223) over 11 years (2007–2017). Firstly, median HCB and p,p′-DDE concentrations increased ~75 % over the study period, whereas median chlordane concentrations doubled (except for oxychlordane). PCB concentrations, in contrast, remained stable over the study period. Secondly, both body mass and clutch size were negatively associated with OC levels, suggesting that females with high lipid metabolism redistributed more OCs from adipose tissue, and that egg production is an important elimination route for OCs. Thirdly, the direct climate effects were assessed using the mean effective temperature (ET: air temperature and wind speed) during incubation, and we hypothesized that a low ET would increase redistribution of OCs. Contrary to expectation, the ET was positively correlated to most OCs, suggesting that a warmer climate may lead to higher OCs levels, and that the impact of ET may not be direct. Finally, potential indirect impacts were examined using the Arctic Oscillation (AO) in the three preceding winters (AOwinter 1–3) as a proxy for potential long-range transport of OCs, and for local spring climate conditions. In addition, we used chlorophyll a (Chla) as a measure of spring primary production. There were negative associations between AOwinter 1 and HCB, trans-chlordane and trans-nonachlor, whereas oxychlordane and cis-chlordane were negatively associated with Chla. This suggests that potential indirect climate effects on eiders were manifested through the food chain and not through increased long-range transport, although these relationships were relatively weak.
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