More than 600 arable soils from Flanders (Northern-Belgium) were analysed for their total acid extractable contents of As, B, Be, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn in order to determine any increase in the natural background values. Samples were taken at random in several municipalities throughout Flanders. Areas with known historical or actual sources of trace element emissions were omitted although in some cases the distance between those sources and the sampling locations was not more than 20 km. The main soil types were, ranging from north to south: sand, loamy sand, light sandy-loam, sandy-loam and loam. In the coastal area, clay soils (sea polders) were sampled. In addition to the analysis of trace elements, the soil texture class, the pH and the carbon content were determined. Macro- or mesonutrients, Ca, K, P, Mg and Na, were determined from a weak acid extract of the soil samples. Correlations between trace elements and macronutrients provide some information about fertilisation practices and heavy metal sources.A limited number of soils showed slightly enhanced levels for As, Be, Cu, Co, Cr Mn, Ni Pb and Zn. In most cases, this could be linked to the regional industrial activities. However, a clear increase for Cu and Zn, above the natural background could be distinguished in areas with low atmospheric heavy metal deposits. In these cases, the excessive use of animal manure in the past may be the reason for this enrichment. However there was no indication that the Cd content of the soil was raised by the use of large amounts of pig slurry and/or by other common agricultural activities.

A photochemical puff-trajectory model (Fotoplume) has been applied to simulate emissions, atmospheric transport and chemical transformations of pollutants from offshore oil and gas production in the North Sea. The above model was used in conjunction with the European Monitoring and Evaluation Programme (EMEP) regional Lagrangian oxidant model. The Fotoplume and EMEP models were used to evaluate the effects of the atmospheric emissions from the oil and gas exploration activity in the Norwegian sector of the North Sea. Deposition of nitrogen and formation of boundary level ozone in Southern Norway due to North Sea emissions of nitrogen oxides (NOₓ), carbon monoxide (CO) and volatile organic compounds (VOC) have been studied. The petroleum activity in the North Sea is calculated to contribute approximately 20% of the nitrogen deposition in the coastal areas of Norway in 1992. In addition, the models were used to estimate the AOT40 ozone exposure levels. The results indicate that emissions from British and Norwegian oil and gas exploitation sector separately contribute to less than 5% each of the AOT40 values for coniferous forests and meadows. Comparison of model calculations with experimental measurements is quite satisfactory and the models show realistic results for both the nitrogen deposition and AOT40 values.