Kortlægning af luftkvalitet langs motorveje

Det er første gang der er foretaget luftkvalitetsmålinger med høj tidsopløsning langs en motorvej i Danmark, og det er ligeledes første gang, at der er opstillet en luftkvalitetsmodel målrettet forholdene omkring motorveje. Endvidere er det første gang, at der er foretaget en systematisk kortlægning langs et større motorvejsnet i et helt amt. Målekampagnen blev gennemført langs Køge Bugt motorvejen ved Greve i en 3 måneders periode i efteråret 2003, hvor der blev målt kvælstofoxider NOx (kvælstofmonoxid (NO) og kvælstofdioxid NO2) i forskellige afstande af motorvejen. Der er endvidere opstillet en luftkvalitetsmodel, som beskriver spredning og omdannelse med udgangspunkt i OML modellen. OML modellen er modificeret, således at den tager hensyn til trafikskabt turbulens. Modellen er evalueret ved sammenligning mellem målinger og modelberegninger. Endvidere er der gennemført modelberegninger for hele 2003 for sammenligning med grænseværdier. Luftkvaliteten er kortlagt langs hele motorvejsnettet i Roskilde Amt i forskellige afstande fra motorvejen i op til 1.000 m, og de beregnede koncentrationer for 2003 er sammenlignet med grænseværdier for luftkvalitet. Befolkningens eksponering for luftforurening langs motorvejsnettet er kortlagt med udgangspunkt i antal mennesker på hver adresse inden for forskellige afstande af motorvejen. Der er gennemført detaljerede beregninger for NO2. Der er endvidere gennemført beregninger for PM10 (partikler under 10 mikrometer), men der gives her en overordnet vurdering pga. usikkerheder i det eksisterende videngrundlag. Beregninger med den opstillede luftkvalitetsmodel for motorveje viser god systematisk overenstemmelse med målinger i forskellige afstande af motorvejen dog således at modellen overestimerer målte gennemsnitsværdier med ca. 10-20% afhængig af afstanden fra motorvejen i den version, som anvendes til kortlægningsformål. Koncentrationen af NOx og NO2 aftager hurtigt med afstanden til motorvejen. NO2 aftager lidt langsommere end NOx pga. kemiske processer. Kortlægningen af luftkvalitetsniveauerne langs hele motorvejsnettet viste, at kun 3 adresser (11 mennesker) har NO2 årsmiddelkoncentrationer over 40 μg/m3 i 2003, hvilket er grænseværdien, der skal være overholdt i 2010. I årene før 2010 opererer man med en tolerancemargin i forhold til grænseværdien. I 2003 er grænseværdien plus tolerancemargin 54 μg/m . På ingen af adresserne overskrides denne værdi, da den højeste værdi var 44 μg/m . De højeste koncentrationer optræder langs Køge Bugt Motorvejen, da trafikken er størst her

The SAM-Krom biomonitoring study shows occupational exposure to hexavalent chromium and increased genotoxicity in Denmark

Background Hexavalent chromium (Cr(VI)) is a carcinogen. Exposure to Cr(VI) may occur in different industrial processes such as chrome plating and stainless steel welding. The aim of this study was to assess occupational exposure to Cr(VI) in Denmark. Methods This cross-sectional study included 28 workers and 8 apprentices with potential Cr(VI) exposure and 24 within company controls, all recruited from six companies and one vocational school. Use of occupational safety and health (OSH) risk prevention measures were assessed through triangulation of interviews, a questionnaire and systematic observations. Inhalable Cr(VI) and Cr-total were assessed by personal air exposure measurements on Cr(VI) exposed participants and stationary measurements. Cr concentrations were measured in urine and in red blood cells (RBC) (the latter reflecting Cr(VI)). Genotoxicity was assessed by measurement of micronuclei in peripheral blood reticulocytes (MNRET). Results At announced visits, a consistent high degree of compliance to OSH risk prevention measures were seen in ‘chromium bath plating’ for both technical devices (e.g. ventilation, plastic balls, sheet coverings) and in the use of personal protective equipment (e.g. gloves, respirators), yet a lesser degree of compliance was observed in ‘stainless steel welding’. The geometric mean of the air concentration of Cr(VI) was 0.26 μg/m3 (95% confidence interval (CI): 0.12–0.57) for the Cr(VI)-exposed workers and 3.69 μg/m3 (95% CI: 1.47–9.25) for the Cr(VI)-exposed apprentices. Subdivided by company type, the exposure levels were 0.13 μg/m3 (95% CI: 0.04–0.41) for companies manufacturing and processing metal products, and 0.81 μg/m3 (95% CI: 0.46–1.40) for bath plating companies. Workers with occupational exposure to Cr(VI) had significantly higher median levels of urinary Cr (2.42 μg/L, 5th-95th percentile 0.28–58.39), Cr in RBC (0.89 μg/L, 0.54–4.92) and MNRET (1.59 ‰, 0.78–10.92) compared to the within company controls (urinary: 0.40 μg/L, 0.16–21.3, RBC: 0.60 μg/L, 0.50–0.93,MNRET: 1.06 ‰, 0.71–2.06). When sub-dividing by company type, urinary Cr (4.61 μg/L, 1.72–69.5), Cr in RBC (1.33 μg/L, 0.95–4.98) and MNRET (1.89 μg/L, 0.78–12.92) levels were increased for workers with potential Cr(VI) exposure in bath-plating companies, and when subdividing by work task, workers engaged in process operation had increased levels of urinary Cr (8.51 μg/L, 1.71–69.5), Cr in RBC (1.33 μg/L, 0.95–4.98) and MNRET (1.89 μg/L, 0.82–12.92) levels. Conclusion This biomonitoring study shows that bath platers were highly exposed to Cr(VI), as suggested by relatively high levels of urinary Cr, Cr in RBC and increased levels of micronuclei. The urinary Cr concentrations were high when compared to the French biological limit value of 2.5 μg Cr/L, corresponding to the Danish occupational exposure limit of 1 μg/m3. This, in turn, indirectly suggests that additional exposure routes than via air may contribute to the exposure. For welders, no statistically significant increases compared to within company controls were observed, however, the observed urinary Cr levels were similar to the levels observed in a European study (HBM4EU), and were higher than the levels observed for welders in Sweden (SafeChrom). In spite of a high degree of self-reported and observed compliance to OSH risk prevention measures during announced visits, the biomarkers of exposure reflecting recent exposure (urinary Cr) or exposure during the last four months (Cr in RBC) may point to variation in compliance to OSH risk prevention measures in general. Reduced occupational exposure to Cr(VI) may be achieved by applying the hierarchy of controls in eliminating or substituting Cr(VI), and the use of more effective technical solutions (e.g. automation)

Increase in invasive group A streptococcal infections and emergence of novel, rapidly expanding sub-lineage of the virulent Streptococcus pyogenes M1 clone, Denmark, 2023

Funding Information: We would like to thank Karina Kaae, Lanni Fugl Niebuhr Nielsen and Joan Nevermann Jensen for their laboratory expertise, and acknowledge the great effort by clinicians and laboratory technicians at hospitals across Denmark and at Landspítali, Reykjavik, in securing samples and data essential for WGS-based surveillance efforts, as well as the dedicated technical staff maintaining and developing the registries and epidemiological databases at the core of national surveillance in Denmark. Publisher Copyright: © 2023 European Centre for Disease Prevention and Control (ECDC). All rights reserved.A highly virulent sub-lineage of the Streptococcus pyogenes M1 clone has been rapidly expanding throughout Denmark since late 2022 and now accounts for 30% of the new invasive group A streptococcal infections. We aimed to investigate whether a shift in variant composition can account for the high incidence rates observed over winter 2022/23, or if these are better explained by the impact of COVID-19-related restrictions on population immunity and carriage of group A Streptococcus. An increase in incidence rates of invasive (iGAS) and non-invasive (nGAS) group A Streptococcus infection has been reported by several countries across Europe during the 2022/23 winter season [1-3]. Through analysis of all whole genome sequencing (WGS) data acquired for national surveillance of iGAS in Denmark since 2018, we aimed to investigate current genomic developments and the impact of emerging lineages on iGAS incidence rates in 2023. In Denmark, iGAS is not notifiable except in case of meningitis, however, test results from all 10 Departments of Clinical Microbiology (DCMs) are submitted to the Danish Microbiology Database (MiBa) [4] and can be used to monitor incidence rates. Iceland also experienced a higher iGAS incidence in early 2023, and we also present Icelandic WGS data on iGAS isolates from 2022 and 2023.Peer reviewe

Continuous methane concentration measurements at the Greenland Ice Sheet-atmosphere interface using a low-cost low-power metal oxide sensor system

Abstract. In this paper, the performance of a low-cost and low-power methane (CH4) sensing system prototype based on a metal oxide sensor (MOS) sensitive to CH4 is tested in a natural CH4 emitting environment at the Greenland Ice sheet (GrIS). We investigate if the MOS could be used as a supplementary measurement technique for monitoring CH4 emissions from the GrIS with the scope of setting up a CH4 monitoring network along the GrIS. The performance of the MOS is evaluated on basis of parallel measurements using a CRDS reference instrument for v over a field calibration period of approximately 100 h. Results from the field calibration period show that CH4 concentrations measured with the MOS is in very good agreement with the reference CRDS. The absolute concentration difference between the MOS and the CRDS reference values within the measured concentration range of approximately 2–100 ppm CH4 were generally lower than 5 ppm CH4, while the relative concentration deviations between the MOS and the CRDS were generally below 10 %. Calculated mean bias error for the entire field calibration period was −0.05 ppm with a standard deviation of ± 1.69 ppm (n = 37 140). The results confirms that low-cost and low-power MOS can be effectively used for atmospheric CH4 measurements under stable water vapor conditions. The primary scientific importance of the study is that it provides a clear example on how the application of low cost technology can enhance our future understanding on the climatic feedbacks from the cryosphere to the atmosphere. </jats:p

Continuous methane concentration measurements at the Greenland ice sheet–atmosphere interface using a low-cost, low-power metal oxide sensor system

Abstract. In this paper, the performance of a low-cost and low-power methane (CH4) sensing system prototype based on a metal oxide sensor (MOS) sensitive to CH4 is tested in a natural CH4-emitting environment at the Greenland ice sheet (GrIS). We investigate if the MOS could be used as a supplementary measurement technique for monitoring CH4 emissions from the GrIS with the scope of setting up a CH4 monitoring network along the GrIS. The performance of the MOS is evaluated on the basis of simultaneous measurements using a cavity ring-down spectroscopy (CRDS) reference instrument for CH4 over a field calibration period of approximately 100 h. Results from the field calibration period show that CH4 concentrations measured with the MOS are in very good agreement with the reference CRDS. The absolute concentration difference between the MOS and the CRDS reference values within the measured concentration range of approximately 2–100 ppm CH4 was generally lower than 5 ppm CH4, while the relative concentration deviations between the MOS and the CRDS were generally below 10 %. The calculated root-mean-square error (RMSE) for the entire field calibration period was 1.69 ppm (n=37 140). The results confirm that low-cost and low-power MOSs can be effectively used for atmospheric CH4 measurements under stable water vapor conditions. The primary scientific importance of the study is that it provides a clear example of how the application of low-cost technology can enhance our future understanding on the climatic feedbacks from the cryosphere to the atmosphere. </jats:p