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An In Vitro Dosimetry Tool for the Numerical Transport Modeling of Engineered Nanomaterials Powered by the Enalos RiskGONE Cloud Platform
A freely available “in vitro dosimetry” web application is presented enabling users to predict the concentration of nanomaterials reaching the cell surface, and therefore available for attachment and internalization, from initial dispersion concentrations. The web application is based on the distorted grid (DG) model for the dispersion of engineered nanoparticles (NPs) in culture medium used for in vitro cellular experiments, in accordance with previously published protocols for cellular dosimetry determination. A series of in vitro experiments for six different NPs, with Ag and Au cores, are performed to demonstrate the convenience of the web application for calculation of exposure concentrations of NPs. Our results show that the exposure concentrations at the cell surface can be more than 30 times higher compared to the nominal or dispersed concentrations, depending on the NPs’ properties and their behavior in the cell culture medium. Therefore, the importance of calculating the exposure concentration at the bottom of the cell culture wells used for in vitro arrays, i.e., the particle concentration at the cell surface, is clearly presented, and the tool introduced here allows users easy access to such calculations. Widespread application of this web tool will increase the reliability of subsequent toxicity data, allowing improved correlation of the real exposure concentration with the observed toxicity, enabling the hazard potentials of different NPs to be compared on a more robust basis.
Ingestion of crumb rubber and uptake of associated contaminants in lumpfish (cyclopterus lumpus)
Car tire rubber represents an important source of microplastics, mainly through abrasion of tire dust on roads, but also in the form of crumb rubber (CR) produced from end-of-life vehicle tires that is used in artificial sport fields, playgrounds and other urban surfaces. CR is known to contain a mixture of different organic chemicals and metals. The leachate of tire particles has previously been shown to be toxic to marine invertebrates and some fish species. Here, lumpfish (Cyclopterus lumpus) were exposed to CR particles (2-4 µm) in seawater for 7 days, followed by a 14-day depuration period. Blood samples were collected from the fish, together with the stomach and gut for visual detection of CR in the fish intestines. A comprehensive non-target screening analysis of organic chemical content in the blood was conducted using HRGC/HRMS (Thermofisher, Orbitrap). In addition to the screening, specific focus was given to quantification of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD) and its degradation product 6PPD-quinone, known toxicants. Tissue samples were also analyzed for metals by ICP-MS. The exposed lumpfish were found to readily ingest CR alongside food under laboratory conditions. The quantity of CR in intestine samples increased during the exposure period, reaching a maximum level directly after the exposure period ended (day 8). A measurable decrease of CR particles was observed throughout the depuration period, although some individuals still contained CR at the end of the depuration period (day 21). The organic chemicals 6PPD and 6PPD-quinone, as well as other CR-related chemicals, were detected in the blood both on day 7 and day 21. No increased in concentration over time was observed for any of the 10 metals were detected in blood of exposed lumpfish. The study confirms that lumpfish actively ingest CR, causing the transfer of CR-related chemicals to the blood.
Monitoring of long-range transported air pollutants in Norway. Annual Report 2021.
This report presents results from the monitoring of atmospheric composition and deposition of air pollution in 2021, and focuses on main components in air and precipitation, particulate and gaseous phase of inorganic constituents, particulate carbonaceous matter, ground level ozone and particulate matter. The level of pollution in 2021 was generally low with few high episodes.
Plastic burdens in northern fulmars from Svalbard: looking back 25 years
The northern fulmar Fulmarus glacialis ingests a larger number of (micro)plastics than many other seabirds due to its feeding habits and gut morphology. Since 2002, they are bioindicators of marine plastics in the North Sea region, and data are needed to extend the programme to other parts of their distribution areas, such as the Arctic. In this study, we provide data on ingested plastics by fulmars collected in 1997 in Kongsfjorden, Svalbard. An extraction protocol with KOH was used and for half of the birds, the gizzard and the proventricular contents were analysed separately. Ninety-one percent of the birds had ingested at least one piece of plastic with an average of 10.3 (±11.9 SD) pieces. The gizzards contained significantly more plastics than the proventriculus. Hard fragments and polyethylene were the most common characteristics. Twelve percent of the birds exceeded the EcoQO value of 0.1 g.
Plastic ingestion and associated additives in Faroe Islands chicks of the Northern Fulmar Fulmarus glacialis
Northern Fulmars (Fulmarus glacialis) are a pelagic seabird species distributed at northern and polar latitudes. They are often used as an indicator of plastic pollution in the North Sea region, but data are lacking from higher latitudes, especially when it comes to chicks. Here, we investigated amounts of ingested plastic and their characteristics in fulmar chicks from the Faroe Islands. Plastic particles (1 mm) in chicks of two age classes were searched using a digestion method with KOH. In addition, to evaluate if additive tissue burden reflects plastic ingestion, we measured liver tissue concentrations of two pollutant classes associated with plastic materials: polybrominated diphenyl ethers (PBDEs) and several dechloranes, using gas chromatography with high-resolution mass spectrometry. The most common shape was hard fragment (81%) and the most common polymer was polyethylene (73%). Plastic contamination did not differ between either age class, and we found no correlation between neither the amount and mass of plastic particles and the concentration of additives. After comparison with previous studies on adult fulmars, we do not recommend using chicks for biomonitoring adults because chicks seem to ingest more plastics than adults.
Environmental pollutants in the terrestrial and urban environment 2021
Samples from the urban terrestrial environment in the Oslo area were analysed for metals and a large number of organic environmental pollutants. The selected samples that were analysed were soil, earthworm, fieldfare egg and liver, brown rat liver, roe deer liver, vegetation, insects and red fox liver. Biomagnification-potential was estimated based on detected data for relevant predator-prey pairs.