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HBr emissions from volcanoes lead rapidly to the formation of BrO within volcanic plumes and have an impact on tropospheric chemistry, at least at the local and regional scales. The motivation of this paper is to prepare a framework for further 3D modelling of volcanic halogen emissions in order to determine their fate within the volcanic plume and then in the atmosphere at the regional and global scales. The main aim is to evaluate the ability of the model to produce a realistic partitioning of bromine species within a grid box size typical of MOCAGE (Model Of atmospheric Chemistry At larGE scale) 3D (0.5∘ × 0.5∘). This work is based on a 1D single-column configuration of the global chemistry-transport model MOCAGE that has low enough computational cost to allow us to perform a large set of sensitivity simulations. This paper uses the emissions from the Mount Etna eruption on 10 May 2008. Several reactions are added to MOCAGE to represent the volcanic plume halogen chemistry. A simple plume parameterisation is also implemented and tested. The use of this parameterisation tends to only slightly limit the efficiency of BrO net production. Both simulations with and without the parameterisation give results for the partitioning of the bromine species, of ozone depletion and of the ratio that are consistent with previous studies.
A series of test experiments were performed to evaluate the sensitivity of the results to the composition of the emissions (primary sulfate aerosols, Br radical and NO) and to the effective radius assumed for the volcanic sulfate aerosols. Simulations show that the plume chemistry is sensitive to all these parameters. We also find that the maximum altitude of the eruption changes the BrO production, which is linked to the vertical variability of the concentrations of oxidants in the background air. These sensitivity tests display changes in the bromine chemistry cycles that are generally at least as important as the plume parameterisation. Overall, the version of the MOCAGE chemistry developed for this study is suitable to produce the expected halogen chemistry in volcanic plumes during daytime and night-time.
2023
Halogenated organic contaminants (HOCs) and mercury in dead or dying seabirds on Bjørnøya (Svalbard). TA-2222/2007
2007
2007
2012
Halogenerte organiske miljøgifter og kvikksølv i norsk ferskvannsfisk, 1995-1999. NIVA-rapport, 4402-01
2001
2010
2019
2019
2011
Haugaland ENØK as. Spredningsberegninger for utslipp til luft fra biobrenselanlegg i Ølen sentrum. NILU OR
2001
2011
Hazard and exposure assessment of do-it-yourself products forimpregnation
A large number of do-it-yourself impregnation products are marketed to Danish consumers. The products are typically used for re-impregnation of consumer products (e.g. footware and outdoor clothing) immediately after the products have been purchased or when the water and/or dirt-repellent effect begins to diminish.
The Danish Environmental Protection Agency has chosen to make a survey of the market, where 110 do-it-yourself impregnation products were identified within ten different application categories. Out of these products, 14 were included in initial chemical content analyzes, as well as hazard and exposure analyzes. The main components in the majority of the products were saturated hydrocarbons, but some of the products also contained oxygen-containing solvents (e.g. alcohols, ethers, esters or ketones). The potential hazard of 12 of the 14 selected impregnation spray products was performed by measuring acute respiratory toxicity. Of the 12 products tested, 10 inhibited the function of the lung surfactant and may therefore potentially be harmful by inhalation.
On the basis of this study, it could not be demonstrated that the products with PFAS resulted in an inhibition of the lung surfactant at lower doses as compared to products without PFAS; in fact, the lowest inhibitory doses were seen for impregnating agents based on siloxanes/silicones. The results show that the hazardous properties of an impregnation product cannot be determined solely on the basis of the ingredients, and it is therefore necessary to examine the ability of the individual products to inhibit the lung surfactant in connection with a hazard assessment.
Danish Environmental Protection Agency
2023
2022
2025
2025
The movement towards an animal-free testing approach for risk assessment represents a key paradigm shift in toxicology. Risk assessment of engineered and anthropogenic nanoscale materials (NM) is dependent on reliable hazard characterization, which requires validated test methods and models, and increasingly on mechanistic insights into the mode of action. The properties that make NMs so advantageous for a wide range of commercial and industrial applications also pose a challenge when it comes to safety testing under in vitro and in chemico experimental settings. Their large reactive surface area makes NMs prone to interactions with assay reagents, readout signals, or intermediate steps of many test assays, leading to the potential for biased results and data inconsistencies, collectively referred to as interferences. Therefore, methods and protocols developed and validated for conventional chemicals often require adaptation and checking for reliability in NMs' toxicity assessment. This review presents the collected scientific knowledge on NMs-induced interferences for the most common in vitro toxicity assays and methods related to cytotoxicity, oxidative stress and inflammatory response evaluation. Our analysis of existing scientific literature showed that the challenge of NMs-induced interference was not explicitly addressed in more than 90% of the papers published up to 2014 reporting the safety and toxicity of NMs. In later years, increasing number of studies tackled the interference challenge in toxicity testing of NMs, which initiated exhaustive work on standardization and validation of existing regulatory-relevant in vitro test protocols and guidelines. Due to the specificity of the different NMs and the range of ways they can potentially interfere with in vitro assays, interference and fit-for purpose controls should be included for each NM type and method applied, unless label-free assays are selected. Here, we provide a decision tree to guide researchers on how to design experiments to avoid interferences during in vitro testing by taking appropriate mitigation actions and how to include proper interference controls in their experimental design where complete avoidance is not possible. The application of this decision tree will improve the reliability, comparability and reusability of in vitro toxicity data on engineered NMs or ENMs, increasing the relevance of in silico hazard data for use in risk assessment and in science-based risk governance of NMs. The approach is applicable more broadly also, to advanced materials and to hazard assessment of anthropogenic nanoscale materials such as microplastic and tyre-wear particles.
Elsevier
2024