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Non-target screening - a powerful tool for selecting environmental pollutants. NILU OR
The main goal with this project was to test the potential and practicalness of the available non-target screening methods for identification of unknown or new emerging environmental pollutants. It was also desired to try to estimate the quantity of the identified compounds.
2013
Wood building materials can be a source of volatile organic compounds (VOCs) in the indoor environment and increasing focus is put on classification and regulation of the use of wood building materials in Europe. The main wood related VOCs such as monoterpenes rarely pose adverse health effects for humans, but as analytical procedures become more sensitive new hazardous VOCs are detected in low concentration. There is a need for comprehensive identification of VOCs emitting from different wood building materials for indoor use. This study performed a first semi-quantitative non-target and suspect screening of VOC emissions from three important wood-based building materials in Europe. Air samples collected from emission chambers were analyzed using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry and resulting mass spectra were classified into confidence groups. A total of 84, 133 and 197 compounds were found to emit from cross-laminated timber, untreated spruce panel and untreated pine panel, respectively. Pine panel was found to emit a higher number of VOCs as well as higher concentrations of most VOCs compared to the spruce building materials. Several new VOCs were detected in the emission profile of pine and spruce. However, they were mostly structurally similar to previously reported wood VOCs. Two compounds of concern emitting from all three wood building materials were furfural and (E)-2-octenal, as these have been classified as group 2 carcinogen and potent eye irritant, respectively.
2025
The Norwegian Arctic possesses a unique environment for the detection of new potential chemicals of emerging Arctic concern (CEACs) due to remoteness, sparse population and the low number of local contamination sources. Hence, a contaminant present in Arctic air is still considered a priority indication for its environmental stability and environmental mobility. Today, legacy persistent organic pollutants (POPs) and related conventional environmental pollutants are already well-studied because of their identification as Arctic pollutants in the 1980s. Many of them are implemented and reported in various national and international monitoring activities including the Arctic Monitoring and Assessment Programme (AMAP). These standard monitoring schemes, however, are based on compound-specific quantitative analytical methods. Under such conditions, the possibility for the identification of hitherto unidentified contaminants is limited and random at best. Today, new and advanced technological developments allow a broader, unspecific analytical approach as either targeted multicomponent analysis or suspect and non-target screening strategies. In order to facilitate such a wide range of compounds, a wide-scope sample clean-up method for high-volume air samples based on a combination of adsorbents was applied, followed by comprehensive two-dimensional gas chromatography separation and low-resolution time-of-flight mass spectrometric detection (GC × GC-LRMS). During the study reported here, simultaneous non-target and suspect screening were applied. The detection of over 700 compounds of interest in the particle phase and over 1200 compounds in the gaseous phase is reported. Of those, 62 compounds were confirmed with reference standards and 90 compounds with a probable structure (based upon mass spectrometric interpretation and library spectrum comparison). These included compounds already detected in Arctic matrices and compounds not detected previously (see also Fig. 1). In addition, 241 compounds were assigned a tentative structure or compound class. Hitherto unknown halogenated compounds, which are not listed in the mass spectral libraries used, were also detected and partly identified.
2020
Long-term monitoring of regulated organic chemicals, such as legacy persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs), in ambient air provides valuable information about the compounds' environmental fate as well as temporal and spatial trends. This is the foundation to evaluate the effectiveness of national and international regulations for priority pollutants. Extracts of high-volume air samples, collected on glass fibre filters (GFF for particle phase) and polyurethane foam plugs (PUF for gaseous phase), for targeted analyses of legacy POPs are commonly cleaned by treatment with concentrated sulfuric acid, resulting in extracts clean from most interfering compounds and matrices that are suitable for multi-quantitative trace analysis. Such standardised methods, however, severely restrict the number of analytes for quantification and are not applicable when targeting new and emerging compounds as some may be less stable under acid treatment. Recently developed suspect and non-target screening analytical strategies (SUS and NTS, respectively) are shown to be effective evaluation tools aimed at identifying a high number of compounds of emerging concern. These strategies, combining highly sophisticated analytical technology with extensive data interpretation and statistics, are already widely accepted in environmental sciences for investigations of various environmental matrices, but their application to air samples is still very limited. In order to apply SUS and NTS for the identification of organic contaminants in air samples, an adapted and more wide-scope sample clean-up method is needed compared to the traditional method, which uses concentrated sulfuric acid. Analysis of raw air sample extracts without clean-up would generate extensive contamination of the analytical system, especially with PUF matrix-based compounds, and thus highly interfered mass spectra and detection limits which are unacceptable high for trace analysis in air samples.
In this study, a novel wide-scope sample clean-up method for high-volume air samples has been developed and applied to real high-volume air samples, which facilitates simultaneous target, suspect and non-target analyses. The scope and efficiency of the method were quantitatively evaluated with organic compounds covering a wide range of polarities (logP 2–11), including legacy POPs, brominated flame retardants (BFRs), chlorinated pesticides and currently used pesticides (CUPs). In addition, data reduction and selection strategies for SUS and NTS were developed for comprehensive two-dimensional gas chromatography separation with low-resolution time-of-flight mass spectrometric detection (GC × GC-LRMS) data and applied to real high-volume air samples. Combination of the newly developed clean-up procedure and data treatment strategy enabled the prioritisation of over 600 compounds of interest in the particle phase (on GFF) and over 850 compounds in the gas phase (on PUF) out of over 25 000 chemical features detected in the raw dataset. Of these, 50 individual compounds were identified and confirmed with reference standards, 80 compounds were identified with a probable structure, and 774 compounds were assigned to various compound classes. In the dataset available here, 11 hitherto unknown halogenated compounds were detected. These unknown compounds were not yet listed in the available mass spectral libraries.
2021
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NO2 emission from the vehicle fleet in major Norwegian cities. Challenges and possibilities towards 2025. TØI rapport, 1168/2011
2011
The Air Quality in Oslo in 2025 will be worse than previously expected. If the present trend of a high percentage of sold diesel passenger cars will continue it will make the NO2 levels from light vehicles higher in 2025 compared with 2010.This is due to higher emissions of diesel cars in real driving cycles compared to the emissions standards. The calculation of NO2 concentrations in 2025 shows levels that will violate the directives¿ limit values in a large area of Oslo.
Calculations are done for 2010 and 2025 and results from totally 9 dispersion calculations are shown. Firstly 4 reference calculations are considered looking at the effect of the difference of real emissions factors taken from measurement under typically urban driving-cycle compared with the emission standards. There have also been done 3 mitigation calculations with incentives for lower diesel cars sales numbers and two short-time measures limiting the use of cars.
None of these measures are sufficient for keeping the limit values in Oslo and Bærum in 2025 and hence more measures are needed.
2011
2016
2016
Nivåer av tungmetaller og PCBer i elgkjøtt fra Sør-Varanger 2020
Under høstjakta på elg (Alces alces) i 2020 ble det tatt vevsprøver til analyser av tungmetaller og PCB. Tungmetallprøver ble tatt av 24 individer; 4 hunnkalver, 4 hannkalver, 3 hanner av åringer og 13 okser (voksne hanner). PCB analyser ble gjort av vevsprøver som ble tatt av 2 hunnkalver, 3 hannkalver, 2 hann-åringer og 9 okser (totalt 16 dyr). De felte dyrene har god geografisk spredning fra sør til nord og nord-øst i kommunen. Tungmetallene som ble analysert var krom (Cr), nikkel (Ni), kobber (Cu), sink (Zn), arsen (As), sølv (Ag), kadmium (Cd), tinn (Sn), bly (Pb) og kvikksølv (Hg). PCB ble analysert for 34 kongenere pluss sumPCB6 og sumPCB7. De fleste konsentrasjonene av tungmetallene var svært lave og flere var under deteksjonsgrensene. Ellers var det bare sporadiske lave forekomster av de 32 PCBene som ble funnet i noen av de undersøkte elgene. Det var bare heksaklorbensen som ble detektert i alle prøvene fra elgene).
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