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Abstract: The Greenlandic population is known to be exposed to heavy metals and persistent organic compounds (POPs) depending on the fraction of their diet coming from sea animals. Long-range atmospheric transport of air pollution to western Greenland, possibly from Canada or USA and in episodes also from Eurasia, is suspected to be a main cause. At Lille Malene Mountain close to Nuuk, the capital of Greenland, continuous monitoring of heavy metals as well as SO2 and sulphate were carried out by a filter pack system. The results are presented and discussed in this article. Sources were identified by a receptor model (COPREM), and model calculations of the concentrations were performed with an Eulerian model (DEHM). The levels of particle bound heavy metals and sulphur were very low. Analysis of data by COPREM showed that sea spray and crustal dust were the dominant source of inorganic particulate mass and that anthropogenic sources contributed with less than 8% of the inorganic particle mass. The measured levels of SO x (sum of and SO2) and Pb in Nuuk were reproduced by DEHM. However, the very low measured values of SO x and Pb concentrations made it impossible to use them to improve and develop model performance of DEHM. [Copyright &y& Elsevier]

Abstract: Fine and coarse fraction PM was simultaneously sampled with Dichotomous Stacked Filter Units at a road site and at an urban background site during both summer and winter periods. The collected mass was determined gravimetrically, and the contents of 26 elements were measured by Proton-Induced X-ray Emission (PIXE). NO x was monitored continuously at both sites. The road increments (road concentrations minus urban background concentrations) of PIXE elements, PM and NO x were analysed using the Constrained Physical Receptor Model (COPREM). Good agreement between the measured data and the model was achieved in both size fractions using four well-separated source profiles representing the emissions from exhaust, road/tyres, brakes and road salt. The analysis showed that the particles created by brake abrasion have aerodynamic diameters in the inhalable size range around 2.8μm. This particle diameter is common mass median for a long list of heavy metals that are apportioned to the brakes source: Cr, Fe, Cu, Zn, Zr, Mo, Sn, Sb, Ba and Pb. Other significant contributions of Al, Si, K, Ca, Ti, Mn, Fe, Zn and Sr, mostly in the coarse particle fraction, are apportioned to the road/tyres source. [Copyright &y& Elsevier]

This review is based on the results obtained from the Danish AMAP programme for the Arctic atmosphere during the 1990s. The purpose of the programme is to quantify the pollution, apportion source contributions, follow the trends, and identify midlatitude source areas and transport pathways. The project has been carried out in North Greenland as integrated monitoring, which is an interacting combination of field measurements and model calculations of atmospheric transport and transformation in the Northern Hemisphere. At the monitoring site at Station Nord the large and seasonally recurrent variations in the pollutant concentrations are testimony to the influence in this region of the phenomenon of Arctic Haze. These results can only be understood in terms of long range transport from distant pollution sources. The measurements also comprise a large number of particle-born elements. These results are used to build receptor models, which show that the ambient concentrations and their variations to a high degree can be explained by the influence of only four source types of both natural and anthropogenic nature. The challenging phenomena of atmospheric ozone and mercury depletion around Polar sunrise have been studied at Station Nord over several years. The results show that these two phenomena are closely connected, presumably through photochemical reactions with atmospheric halogens released from sea ice. A large-scale Eulerian model system for the Northern Hemisphere has been developed in this AMAP project. The validity of the model is illustrated by comparisons between measured and calculated air concentrations. The model has been used to calculate both the vertical distribution and the atmospheric depositions for several pollutants at various locations in Greenland and split into quantified contributions from different and geographically distant source areas. Mercury deposition estimates for the Northern Hemisphere are also presented. They show that the mercury depletion events are accompanied by very intense depositions to land and sea of reactive mercury that may seriously affect the Arctic ecosystems. Finally, measurement and model data are combined to demonstrate, despite considerable meteorological noise, that ambient air concentrations in North-eastern Greenland have decreased during the last decade. Quantified trends, attributable to emission reductions in distant source areas, are presented for several pollutants. [Copyright &y& Elsevier]

In order to carry out efficient traffic and air quality management, validated models and PM emission estimates are needed. This paper compares current available emission factor estimates for PM10 and PM2.5 from emission databases and different emission models, and validates these against eight high quality street pollution measurements in Denmark, Sweden, Germany, Finland and Austria. The data sets show large variation of the PM concentration and emission factors with season and with location. Consistently at all roads the PM10 and PM2.5 emission factors are lower in the summer month than the rest of the year. For example, PM10 emission factors are in average 5–45% lower during the month 6–10 compared to the annual average. The range of observed total emission factors (including non-exhaust emissions) for the different sites during summer conditions are 80–130mgkm−1 for PM10, 30–60mgkm−1 for PM2.5 and 20–50mgkm−1 for the exhaust emissions. We present two different strategies regarding modelling of PM emissions: (1) For Nordic conditions with strong seasonal variations due to studded tyres and the use of sand/salt as anti-skid treatment a time varying emission model is needed. An empirical model accounting for these Nordic conditions was previously developed in Sweden. (2) For other roads with a less pronounced seasonal variation (e.g. in Denmark, Germany, Austria) methods using a constant emission factor maybe appropriate. Two models are presented here. Further, we apply the different emission models to data sets outside the original countries. For example, we apply the “Swedish” model for two streets without studded tyre usage and the “German” model for Nordic data sets. The “Swedish” empirical model performs best for streets with studded tyre use, but was not able to improve the correlation versus measurements in comparison to using constant emission factors for the Danish side. The “German” method performed well for the streets without clear seasonal variation and reproduces the summer conditions for streets with pronounced seasonal variation. However, the seasonal variation of PM emission factors can be important even for countries not using studded tyres, e.g. in areas with cold weather and snow events using sand and de-icing materials. Here a constant emission factor probably will under-estimate the 90-percentiles and therefore a time varying emission model need to be used or developed for such areas. All emission factor models consistently indicate that a large part (about 50–85% depending on the location) of the total PM10 emissions originates from non-exhaust emissions. This implies that reduction measures for the exhaust part of the vehicle emissions will only have a limited effect on ambient PM10 levels. [Copyright &y& Elsevier]

Epidemiological studies have consistently shown relation between exposure to particulate matter in urban air and cardiovascular and pulmonary morbidity and mortality. Some recent population studies suggest that the ultrafine fraction of particulate matter generated by motorised vehicles is particularly damaging. Animal studies and cell culture experiments support this hypothesis and address the possible mechanisms of action. Inhalation of particulate matter, especially ultrafine particles, causes oxidative stress and inflammation in lung tissue, which affects the lung cells per se, as well as the cardiovascular system.

Introduction: Ambient air pollution is a risk factor for mortality and morbidity. The aim of this study was to quantify the health effects related to particulate matter (PM10) in Denmark., Materials and Methods: We used relative risk estimates in relation to PM10 based on the epidemiological literature. Population exposure to PM10 was calculated. Cases attributable to PM10 were estimated for mortality, cardiovascular and respiratory hospital admissions, chronic bronchitis, acute bronchitis, restricted activity days, and asthma attacks. Moreover, we attempted to estimate health-related gains from equipping all heavy-duty vehicles in Denmark with particle filters., Results: We estimated the average population PM10 exposure to be about 22 micrograms/m3, about one third of which can be attributed to natural (not man-made) PM10. The number of cases per year attributable to the estimated exposure included about 5,000 deaths, about 5,000 hospital admissions, about 5,000 cases of chronic bronchitis, about 17,000 cases of acute bronchitis, about 200,000 asthma attacks, and about three million restricted activity days. The health-related gains from installing particle filters on all heavy-duty vehicles in Denmark are uncertain; the estimates for mortality ranged from 22 to 1,250, depending on the assumptions., Discussion: Although air pollution constitutes only a minor risk factor on the individual level, it seems to be a major public health problem. The particle characteristics responsible for the estimated health effects are not well understood. The ultrafine particle fraction may cause a much greater impact on health than indicated by the mass.