Found 300 publications. Showing page 7 of 13:
2022
2024
2022
2018
Crumb rubber toxicity in coastal marine systems
Crumb rubber granulate (CRG) produced from end of life tires (ELTs) is commonly applied on indoor and outdoor synthetic turf pitches (STPs), playgrounds, safety surfaces and walkways. In addition to fillers, stabilizers, cross-linking agents and secondary components (e.g. pigments, oils, resins, fibers), ELTs contain high levels of organic additive compounds and heavy metals. While previous environmental studies have focused on terrestrial soil and freshwater ecosystems, in Norway many sites applying CRG are coastal. In the current study, the organic chemical and metal content of 'fresh' and 'weathered' CRG and their seawater leachates was investigated, and the uptake of crumb rubber by the brown crab (Cancer pagurus) was studied as an example of an exposure route for CRG to coastal marine organisms. A combination of pyrolysis gas chromatography mass spectrometry (py-GC-MS) and chemical extraction followed by GC-MS analysis revealed similar organic chemical profiles for pristine and weathered CRG, including additives such as benzothiazole, N-1,3-dimethylbutyl-N'-phenyl-p-phenylenediamine and a range of polycyclic aromatic hydrocarbons (PAHs) and phenolic compounds (e.g. bisphenols). ICP-MS analysis indicated g/kg quantities of Zn and mg/kg quantities of Fe, Mn, Cu, Co, Cr, Pb and Ni in the CRG. A mixture of organic additives, metals and other inorganic compounds readily leached from the CRG into seawater. Benzothiazole was the organic compound with highest concentration (average of 136 mg/L), while PAHs (ranging from <LOD to 0.58 mg/L) and phenolic compounds (e.g. 2,4-bisphenol F and 4,4’-bisphenol F at 0.012 and 0.006 mg/L, respectively) were present in low abundance. Zn was the most abundant metal in the leachates (23.8 mg/L) followed by Fe (0.08 mg/L) and Co (0.06 mg/L). While organic chemical concentrations in the leachates stabilized within days, metals continued to leach out over the 30 day period. Brown crabs were exposed to two concentrations of CRG (0.5 and 0.05 g/L) in two size fractions (5 mm and 250 µm diameter) for 24 hours. Ingestion of the rubber and subsequent gut evacuation were studied over 5 days. Image analysis of filtered stomach contents confirmed uptake of rubber particles in different sizes, but also efficient gut evacuation upon transfer to clean water. We discuss the implications of CRG and leachate toxicity in acute and long-term exposure scenarios for marine coastal ecosystems.
2020
2018
Here we provide an overview of the newly commenced project ‘ReGAME - Reliable Global Methane Emissions estimates in a changing world’, funded by Research Council of Norway from 2021-2025, where we combine new developments in atmospheric methane observations: isotopic ratios (deuterium and 13C in methane), and the Integrated Carbon Observation System (ICOS) ground-based station network with atmospheric models (the chemistry transport model OsloCTM, and inversion model FLEXINVERT) to understand how and why atmospheric methane levels are increasing. The project has a particular focus on understanding the state of Arctic methane reservoirs such as ocean seeps and high latitude wetlands. This includes plans for a new observing system aboard the ice breaking vessel RV Kronprins Haakon and ocean observations, e.g., dynamics of Seep fluxes assessed during 1 year of continuous measurements at a seep site the NorEMSO project, updated information on spatial seep distribution via echo sounding, as well as high resolution high-latitude inversion modeling of atmospheric methane with FLEXINVERT. Furthermore, we investigate the utility of including of satellite data (TROPOMI aboard the Sentinel 5P mission) together with ground-based data, in inversion modeling. The inclusion of satellite data into inversion models is quite novel and offers rewards by increasing spatial coverage compared to ground based networks alone, potentially reducing uncertainties in the model outputs, and challenges due to satellite data uncertainties, spatial/ temporal coverage, and handling large data fields
2022
2019
2019
2018
2018
Field measurements of indoor air in one Norwegian School
Surveys conducted in Norwegian schools showed students have experienced health problems, such as headaches or concentration issues which have been linked to indoor air quality (IAQ). Since no standard assessment method/protocol for IAQ exists, the assessment of IAQ by measurements will be influenced by type of monitoring device and its placement. The aim of this study is to evaluate the condition of indoor air parameter in school buildings. This work was conducted by investigating the influence of specification and placement of measurement devices of IAQ in a primary school building in Oslo City, as part of a broader investigation to identify potential measures to improve IAQ. Field measurements were done using both additional sensors, and existing sensors by the building energy management system. Different sensors were installed in classrooms in the school at slightly different locations. Measurement results of carbon dioxide and temperature were compared and evaluated in three different classrooms in the school. The result indicates that some classroom in the school may slightly not have a satisfactory IAQ. The comparison analysis suggests that room occupancy and sensor placement and specification influence the measurement results, and may thus negatively influence decisions made to ventilation system on the basis of the data from existing measurement. Further investigation is needed to understand the reliability of existing sensors to evaluate the IAQ of school buildings.
2023
2019