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Concentrations of several trace elements have been measured in air samples collected simultaneously at four remote stations from SW Sweden, along the Norwegian coast to north Finland. The samples showed that the background aerosol had a large spatial variation in elemental composition. During cases of long-range transported air pollution (episodes), concentrations of pollutants were several times higher than the background concentrations. Generally, the background concentration profile varied, showing a decrease in concentrations towards northwest. The levels of some elements were elevated at the northernmost station as a result of influence from the industrialised areas at the Kola Peninsula. Trends of concentrations from 1985 and onwards were followed at one of the sites. The highest concentration of trace elements in the fine fraction of particles was observed in the mid-1980s, and a considerable decrease is observed during later years. Elemental signatures were calculated and compared with the same ratios from large source areas.

Extensive measurements of airborne concentrations and deposition fluxes of many major and trace species were performed within the framework of the BMCAPE project (Background Maritime Contribution to Atmospheric Pollution in Europe) at two Scandinavian sites (Saby in Sweden and Lista in Norway) during four seasons in 1993 and 1994. The study focused on gaseous and particulate S-, N- and CI-species. Airborne concentration levels during the different campaigns, seasons and the various air masses encountered are presented for the following gaseous and particulate species: SO2, HCl, NOx HNO3, NH3, SO42−, NH4+, NO3−, S, Cl, K, Ca, V, Ni, Zn, Br, Pb and condensation nuclei. In addition, particle concentrations of Ti, Fe, Cu and Mn are discussed in the text. A time series is given for particulate and gaseous Hg. Annual flux estimates for Southern Scandinavia are given for Mn, Fe, Ni, Cu, Zn, Ph, Cl, S, non-sea-salt-sulphate-S, As, Na, K, Ca, Mg, NO3−N and NH4+N. Based on direct flux measurements to a water surface, dry deposition velocities are determined for nine elements: Mn, Fe, Ni, Cu, Zn, Ph, Cl, S, Ca.

The present work provides insights into the N- and S-pollution behaviour at rural and remote sites in Northern Europe. Formation of SO42− and NO3− from their precursor gases receives special attention in order to understand the significance of chemical conversion in shaping the distributions of concentration and deposition monitored at our sites: Saby—on the Swedish west coast, Lista—on the Norwegian south coast and South Uist—on the Hebride Islands in Northern Scotland. Owing mainly to the complexity of the problem, the approach is semiquantitative. Concentration patterns of S- and N-compounds for air mass transport between the sites were investigated for 10 periods (13 d), within continental (6 d) and oceanic (7 d) air masses. The observations spanned over both winter and summer days and conclusions could be drawn in some cases with respect to seasonality. The measurements were performed during the BMCAPE (Background Maritime Contribution to Atmospheric Pollution in Europe) project in 1993 and 1994. S- and N-ratios were used as indicators of air mass age, chemical conversion efficiency and “en-route” deposition. The S-ratio is defined as the ratio of particulate S (as SO42−) to total S (as SO2 and SO42−). The N-ratio is taken as the ratio of gaseous HNO3-N over particulate NO3−-N. S-ratios at Saby and Lista agreed very well in those cases when no or insignificant precipitation occurred. Higher S-ratios and lower N-ratios were typical for conditions of high relative humidity. It is conceivable that condensed phase chemistry was of major importance in the SO2 oxidation and that HNO3 was absorbed onto the wet aerosol particles. Stagnation of the air masses over source regions of high emission densities and rates resulted in accumulation of pollution, the S-ratios in such conditions being high due to the longer transport time. The S-ratios for marine air flow at Saby and Lista no longer agreed (higher at Lista) as in the case of continental air masses. The reason is likely to be the proximity of the Lista station to the sea. Lista was highly affected by sea spray produced by the strong westerly winds. The N-ratio remained very low in the case of maritime air masses due to unexpectedly high NO3− concentrations. It is conceivable that the high load of NO3− is due to sea spray of surface water. More efficient SO2 deposition over land than over sea has been observed in the westerly airflow by the relative loss of SO2 while the flow swept over land.

Long distance transport of various air pollutants has been studied at two Scandinavian coastal sites. The measuring period has covered one year divided into 4 campaigns. Seasonal variations for sulphur and nitrogen compounds as well as anthropogenically emitted metals are reported. Concentrations of Pb and Zn as well as the ratio of V/Ni concentrations have been used to trace sulphuric episodes. Covariation of anthropogenic pollutants for the two sites is demonstrated.

Mineral dust in the atmosphere is generally alkaline, and is a source of base cations in precipitation. Annual emissions of particles from large combustion plants and industrial processes in Europe is of the order of 24 million tonnes, and the calcium content may be as high as 1.4 million tonnes. Emissions from diffuse sources such as agricultural activities, construction and quarrying are much less well known. Emissions of dust from the Sahara have been estimated to more than 200 tonnes, with a calcium content of 3–5%.

The flux of trace metals into the Arctic atmosphere between 0 and 3.5 km altitude for the period July 1979-June 1980 was determined using a chemical transport modeling approach used previously for sulfur. The total annual flux of antimony. arsenic. cadmium, lead, zinc and vanadium into the Arctic from Eurasia was 4.285.47. 2400, 1350 and 474 tonnes. respectively. This represents 3.4,6.0,4.2.3.0.3.1 and 1.7% of the source emissions. respectively. In contrast, the corresponding flux of sulfur was 2.2 million tonnes or 6.7% of the total emissions. The following percentage contributions to the total flux, of all six metals, by the source regions were calculated: western Europe (7-34%). eastern Europe (42-54%) and the Soviet Union (2l-39"/0). The model also showed that in addition to a late winter (February, March) maximum input to the Arctic, a peak was also observed in October. This peak was shown to have resulted from an unusual set of synoptic conditions, which produced a strong northerly Row into the Arctic around 0" longitude in October 1979. Comparison of the model-predicted trace metal concentrations with a set of limited observations at existing sampling stations close to the Arctic Circle (namely Ny Alesund in Spitsbergen, Jergul, Skrova and Jan Mayen) showed agreement within a factor of 2-3. Key word index: Trace elements, Lagrangian chemical transport model, Eurasian source contributions, Arctic metal deposition. height anomaly gradients.

Atmospheric aerosol samples were collected during spring sampling campaigns in 1988 and 1989 at Birkenes and Nordmoen in southern Norway. The aerosol collectors used included stacked filter units (SFUs), a low volume sampler (referred to as ILVS), which consists of a filter preceded by three impaction stages, and an 11-stage Berner low-pressure impactor (LPI). All samples were analyzed for up to about 40 elements by INAA and PIXE. The resuls obtained from parallel samplings were intercompared in terms of ratios ILVS/SFU and LPI/SFU, whereby these ratios were calculated separately for the coarse and fine size fractions. For the ILVS/SFU parallel samplings, excellent agreement was observed between the results for the fine fraction, with the overall mean average ratio (based on 21 samples and 22 elements) being 0.99±0.10. For the coarse fraction, the overall mean ILVS/SFU ratio (based on 21 elements) was 0.75±0.13. This low result is explained by different upper-particle-size cut-offs of the two samplers. For the parallel samplings with LPI and SFU, the agreement was poorer, but still reasonable. The atmospheric concentrations observed at the two sites in the two campaigns and also the LPI size distributions for the various elements are discussed briefly.

Preliminary estimates of Hg emissions from anthropogenic sources in Europe have been prepared to meet the request of air pollution transport modeling. Major emphasis was placed on four source categories: 1) combustion of fossil fuels, 2) non-ferrous metal production, 3) waste related sources, and 4) chlor-alkali production. Three chemical species: elemental, bivalent and particulate Hg were considered in these estimates. The emission estimates were spatially distributed within the EMEP grid of 150 km × 150 km for the year 1982.

A single orifice cascade impactor was used to collect size-fractionated aerosol samples in Birkenes, Southern Norway, during the spring of 1987. The samples were analyzed for about 20 elements by particle-induced X-ray emission (PIXE). On the basis of the average size distributions and mass median diameters (MMDs), the elements could be classified in three different groups. Mg, Al, Cl, Ca, Ti, and Fe exhibited a unimodal size distribution, with a MMD of about 4 μm equivalent aerodynamic diameter (EAD); for Si, K, Cr, Mn, Ni, and Cu the distribution was rather flat or bimodal; and S, V, Br, Zn, and Pb were predominantly associated with

Data on current and historical usage of alpha, beta, and gamma-hexachlorocyclohexane (HCH) in Europe are presented. The data were collected and estimated as a part of a project studying the regional cycling of persistent organic pollutants (POPs) in the Baltic environment (Popcycling-Baltic). Better data on sources, environmental discharges and atmospheric emissions of HCH and other POPs are needed to study, and hopefully reduce, the impact of these pollutants on the environment. Substantial uncertainties are assigned to the estimated data for individual countries and years, but it seems likely that the general trend of usage in Europe is captured. The quality of the estimates is thought to improve in general throughout the period, thus, reflecting the availability of reliable data. The results suggest that 382,000 t of technical HCH and 81,000 t of lindane were used in Europe from 1970 to 1996. This is equivalent to an estimated cumulative usage of 259,000 t alpha-HCH, 235,000 t gamma-HCH and 20,000 t beta-HCH. The usage of technical HCH was the major source of gamma-HCH until the late 1970s, and thereafter lindane became the dominating source of this isomer. The use of gamma-HCH in 1996 was estimated to still be nearly one-third of the European usage in 1970. The pattern of decreasing concentrations in biota follows the pattern of reductions in usage for the studied period within the Baltic area.

Working Group I discussed atmospheric fluxes and behavior of mercury upon release to the air. Discussion was focused on: atmospheric processes, anthropogenic sources, modeling of transport and Hg transformations, atmospheric measurements, and links of the atmospheric Hg to other parts of the ecosystem.

Although quite extensive information exists on environmental and health effects of mercury and its behavior in the environment, much less information is available on the emission fluxes of the element. Preliminary studies conclude that on the global scale the Hg emission to the air is comparable with direct inputs of the element to the aquatic environment and are almost a half of the direct releases to the terrestrial environment. Thus, the atmosphere is an important pathway for mercury cycling in the environment. Globally, combustion of fossil fuels to produce electricity and heat is the major source of atmospheric emissions of Hg. Both national and regional emission inventories indicate that the combustion of fuels, particularly coal, emits more than half of the atmospheric Hg in Europe. Major portion of Hg emissions from combustion of fuels is in a gaseous phase. In the combustion zone Hg present in coal or other fossil fuels evaporates in elemental form and then most likely a portion of it is oxidized while in the flue gases. The oxidized forms of Hg can be retained in modern flue gas cleaning systems. Refuse incineration seems to be the second largest source of Hg emissions to the atmosphere. Emission generation process for Hg during the incineration of wastes is similar to that during combustion of fossil fuels. However, more Hg in the oxidized form is expected from incinerators due to the higher content of chlorine in the wastes compared to fossil fuels.

There is clear evidence from the global mercury cycle that there is an urgent need for actions to reduce global anthropogenic mercury emissions. A legally- binding global agreement to reduce emissions of mercury is soon in place, meaning that many countries need to take steps to lower their emissions. Identification and assessment of policy options that already are in place as well as setting pollution control objectives and developing effective strategies to meet these objectives, are depending on a decision support tool that allows for identifying current and future environmental problems and to reduce these problems by providing a holistic management approach. Recent scientific advancement allows a more complete picture of the mercury problems and solutions to the problems, which is of outmost interest when it comes to justifying spending resources on the relevant measures. To make sure that resource allocation is favoring human welfare, the economic costs of introducing these measures need to be compared to their economic benefits. The major goal of this study was to provide a novel combination of assessment tools that form a framework for a decision support system towards environmental policy on mercury in Europe. The decision support tool was intended to act as a guideline for policy makers for the purpose of introducing cost- effective abatement of mercury. It was for the EU 27 countries demonstrated that large economic benefits can be achieved globally with reduced mercury emissions in the EU region. The investigated Baseline scenario thus highlighted the importance of full implementation of existing measures and the importance of making further progress in reducing mercury emissions from European sources. Reducing emissions in developing countries may however, be more cost effective, which basically reconfirms the need for a global convention on mercury.

Global and regional emission inventories of mercury are reviewed with special emphasis on the source regions with potential impact on the Arctic environment. These sources are located mostly in Eurasia and North America and emit almost 1300 t ofHg to the air annually. Combustion of fossil fuels to produce electricity and heat is the major source ofHg. Major portion of the element emissions from this source is in a gaseous phase. A small portion of Hg emissions in Eurasia and North America is deposited in the Arctic region, perhaps 60 to 80 t annually. Additional amounts of Hg in the Arctic air originate from natural sources, although it is very difficult to quantify them. A small decrease of anthropogenic Hg emissions is observed in Europe at present. These emissions are expected to increase again in the near future.

Individual and population doses, to which human organs are exposed, were analyzed. These doses are due to coal‐fired power plants. The effect includes contamination by inhalation and contamination by digestion of contaminated food (the latter being dependent on the contamination level in soils, vegetation, water and animals). A percentage distribution of radio‐nuclide doses in individual human organs is given. The highest doses, to which the human organism is exposed, are those to bone. This is associated with the high activities of air‐borne 226Ra and 228Ra, and the concentration of these radionuclides in the coal burnt. In addition, bone is the critical organ for 226Ra and 228Ra. The results obtained are compared with admissible ICPRvalues, which are too high and can no longer be representative. Radionuclide doses due to coal‐fired power plants are compared with those due to nuclear power stations. This comparison shows that radioactive contamination caused by coal‐fired power plants is about 30 times h...

Technological parameters of various industrial processes have a significant influence on the atmospheric emissions of trace elements. Burning the same amount of fuel in different types of boilers or producing the same amount of industrial goods by different technologies results in a difference of the trace element emissions to the atmosphere by sometimes a few orders of magnitude. The choice of production technology and type of air pollution abatement technology are the main tools to control the atmospheric emissions of trace elements. It is also recognized that the modern developments in pollution control technology, such as flue gas desulphurization and fluidised bed combustion also promote trace element retention. The differences in atmospheric emissions of trace elements using various industrial technologies, are illustrated using the 1982 emission survey for As, Cd, Hg, Pb and Zn in Europe.

Anthropogenic emissions of trace elements to the atmosphere are an inherent part of industrial processes. Throughout the last six thousand years of recorded history, man has developed and used industrial processes to prepare metals for military and agricultural use, as well as for coins and jewelry. The records are incomplete for the total amount of metals used and for the quantity of metals emitted to the atmosphere. Nevertheless, it is clear that, in some regional cases, such emissions have exceeded flux from natural sources by several orders of magnitude.