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The Opinion of the Scientific Committee on Health, Environmental and Emerging Risks advises the European Commission on whether the uses of titanium dioxide in toys and toy materials can be considered to be safe in light of the identified exposure, and the classification of titanium dioxide as carcinogenic category 2 after inhalation. Four toy products including casting kits, chalk, powder paints and white colour pencils containing various amounts of TiO2 as colouring agent were evaluated for inhalation risks. For the oral route, childrens’ lip gloss/lipstick, finger paint and white colour pencils were evaluated.
When it can be demonstrated with high certainty that no ultrafine fraction is present in pigmentary TiO2 preparations used in toys and toy materials, safe use with no or negligible risk for all products considered is indicated based on the exposure estimations of this Opinion. However, if an ultrafine fraction is assumed to be present, safe use is not indicated, except for white colour pencils.
Elsevier
2024
An extraordinary charge transfer kinetics and chemical stability make a boron-doped diamond (BDD) a promising material for electrochemical applications including wastewater treatment. Yet, with flat geometrical surfaces its scaling options are limited. In this study, the reticulated Vitreous Carbon (RVC) served as a substrate for boron-doped diamondized nanocarbons (BDNC) film growth resulting with complex heterogeneity carbon structures with different morphologies defined by using electron microscopy, microtomography, activation energy studies, and Raman spectroscopy.
The proposed modification significantly boosted the electrochemical Fe(CN)63−/4− redox activity. The voltammetry and impedimetric studies revealed its origin as a significantly higher share of electrochemically active sites at the BDNC@RVC electrode (increased by 114 %) combined with enhanced heterogeneous rate constant (2× increase up to 8.24·10−4 cm s−1). Finally, to establish its applicability for water treatment, the BDNC@RVC was studied as the anode in electrochemical paracetamol decomposition. Boron-enriched nanoarchitecture formed at the RVC electrode surface substantially reduced the oxidation energy barrier manifested as a decrease in activation overpotential by 212 mV, which gave a consequence in a 78 % removal rate (in 4 h, at 0.7 mA cm−2), 12 % higher than bare RVC and yielding lower amounts of APAP decomposition intermediates.
2024
2024
Phosphorus is a building block for all life and therefore plays an essential role in food production. Currently, large amounts of phosphorus enter the Norwegian food system from abroad in the form of mineral fertilizer, feedstuff, food, as well as micro-ingredients for animal feed, mainly in salmon farming. However, only a small fraction of this phosphorus ends up as food for humans, while the largest part accumulates in soil and water systems. This inefficiency entails two challenges:
1. Phosphorus supply is critical. Phosphate rock, the primary source of phosphorus for fertilizer and micro-ingredient production, is a limited resource that is highly concentrated in a few countries. Over 80% of global phosphate rock reserves are found in only 5 countries, and ~70% are located in Morocco and Morocco-occupied Western Sahara. The high concentration renders many countries vulnerable to geopolitical and economic instabilities and threatens food safety. The EU has therefore included phosphate rock on its list of Critical Raw Materials.
2. The accumulation of phosphorus in water systems can lead to eutrophication and dead zones, threatening fish stocks and other aquatic life. The high phosphorus concentration in soils due to overfertilization over long periods of time increases the danger of losses to water systems by runoff, further exacerbating the eutrophication risk.
A more circular use of phosphorus could simultaneously reduce supply and pollution risks. This is particularly relevant in Norway, where the government has an ambition to increase salmon and trout production from currently 1,5 to 5 million tons by 2050.
Achieving a circular phosphorus economy is a complex task: (i) The land- and the sea-based food systems are increasingly interlinked, for example through agricultural production of fish feed or the application of fish sludge on agricultural land. (ii) The Norwegian phosphorus cycle is increasingly interlinked with that of other countries as trade flows along the entire food supply chain are growing. (iii) Phosphorus fertilizers, both primary and recycled, are often contaminated with heavy metals such as cadmium, uranium, and zinc, which tend to accumulate in soils. Cleaning the phosphorus cycle is therefore vital for soil fertility and human health.
This report is based on the MIND-P project, which studied the Norwegian phosphorus cycle for both agriculture and aquaculture at a farm-by-farm basis and explored options for increasing circularity. The project identified farm-level and structural barriers to managing phosphorus resources more effectively.
We propose four fundamental strategies to overcome these barriers:
1. Develop and maintain a national nutrient accounting.
2. Minimize phosphorus losses and accumulations at farm level.
3. Establish infrastructures for capturing, processing, trade, and use of manure and fish sludge to produce high-quality recycled fertilizers that are tailored to the needs of the users in Norway and abroad.
4. Adopt a regulatory framework to promote a market for recycled fertilizer.
The strategies proposed here were developed with the support of an Advisory Panel consisting of representatives from government, industry, industry associations, and NGOs in an online and two physical workshops conducted in 2022.
NTNU Open
2023
2023
2023
2023
Trends in polar ozone loss since 1989: potential sign of recovery in the Arctic ozone column
Ozone depletion over the polar regions is monitored each year by satellite- and ground-based instruments. In this study, the vortex-averaged ozone loss over the last 3 decades is evaluated for both polar regions using the passive ozone tracer of the chemical transport model TOMCAT/SLIMCAT and total ozone observations from Système d'Analyse par Observation Zénithale (SAOZ) ground-based instruments and Multi-Sensor Reanalysis (MSR2). The passive-tracer method allows us to determine the evolution of the daily rate of column ozone destruction and the magnitude of the cumulative column loss at the end of the winter. Three metrics are used in trend analyses that aim to assess the ozone recovery rate over both polar regions: (1) the maximum ozone loss at the end of the winter, (2) the onset day of ozone loss at a specific threshold, and (3) the ozone loss residuals computed from the differences between annual ozone loss and ozone loss values regressed with respect to sunlit volume of polar stratospheric clouds (VPSCs). This latter metric is based on linear and parabolic regressions for ozone loss in the Northern Hemisphere and Southern Hemisphere, respectively. In the Antarctic, metrics 1 and 3 yield trends of −2.3 % and −2.2 % per decade for the 2000–2021 period, significant at 1 and 2 standard deviations (σ), respectively. For metric 2, various thresholds were considered at the total ozone loss values of 20 %, 25 %, 30 %, 35 %, and 40 %, all of them showing a time delay as a function of year in terms of when the threshold is reached. The trends are significant at the 2σ level and vary from 3.5 to 4.2 d per decade between the various thresholds. In the Arctic, metric 1 exhibits large interannual variability, and no significant trend is detected; this result is highly influenced by the record ozone losses in 2011 and 2020. Metric 2 is not applied in the Northern Hemisphere due to the difficulty in finding a threshold value in enough of the winters. Metric 3 provides a negative trend in Arctic ozone loss residuals with respect to the sunlit VPSC fit of −2.00 ± 0.97 (1σ) % per decade, with limited significance at the 2σ level. With such a metric, a potential quantitative detection of ozone recovery in the Arctic springtime lower stratosphere can be made.
2023
2023
Troll observing network – for useful new data about Antarctica
What do Antarctic petrels in Svarthamaren, soil structure movements at Troll research station and ocean chemistry in the Håkon VII Sea have in common? They will all be studied at the Troll observing network currently being established at Troll research station in Dronning Maud Land in Antarctica.
2023
Phthalate contamination in marine mammals off the Norwegian coast
Phthalates are used in plastics, found throughout the marine environment and have the potential to cause adverse health effects. In the present study, we quantified blubber concentrations of 11 phthalates in 16 samples from stranded and/or free-living marine mammals from the Norwegian coast: the killer whale (Orcinus orca), sperm whale (Physeter macrocephalus), long-finned pilot whale (Globicephala melas), white-beaked dolphin (Lagenorhynchus albirostris), harbour porpoise (Phocoena phocoena), and harbour seal (Phoca vitulina). Five compounds were detected across all samples: benzyl butyl phthalate (BBP; in 50 % of samples), bis(2-ethylhexyl) phthalate (DEHP; 33 %), diisononyl phthalate (DiNP; 33 %), diisobutyl phthalate (DiBP; 19 %), and dioctyl phthalate (DOP; 13 %). Overall, the most contaminated individual was the white-beaked dolphin, whilst the lowest concentrations were measured in the killer whale, sperm whale and long-finned pilot whale. We found no phthalates in the neonate killer whale. The present study is important for future monitoring and management of these toxic compounds.
Elsevier
2023
2023
2023
2023