Future research work at the mine area should also concentrate on both PM10 and PM2.5 measurements and their heavy metal concentrations in the mine area. Such a study would provide information on the human exposure to those particle fractions that can possibly penetrate the lungs. The concentrations of asbestos and other mineral fibres should also be measured in order to gain information on possible human exposure in the mine area. In addition, occupational exposure measurements of airborne dust, fibrous minerals and crystalline silica, e.g. the particle size distribution of mineral phases and metals in dust, at different work-sites and in the underground mine gallery are necessary. Silicosis, the lung condition caused by the inhalation of respirable-size fine particles of crystalline silica, is a potential threat in mine works (49, 156, 202). In addition, limited evidence of the potential carcinogenic effect of silica dust has been reported (54, 203). The content of chromium(III) and chromium(VI) species, as well as the speciation of other metals in workplace air in the mine area and in the underground mine gallery, should be determined in order to assess the occupational risk for workers.
Future research work in the area around the ferrochrome and stainless steel works should focus on the concentration and fractions of heavy metals in the soil and in vegetables in order to provide information about the “contaminant” levels in the area around the works. Bioavailability and environmental mobility studies on heavy metals in the soil are also needed.
Future research work in the area around the pulp and paper mills at Kemi should concentrate on the effects of emissions of gaseous chlorine compounds on the forests, and on a questionnaire study (population panel); odour dispersion calculations and field inspections are primarily tools for measuring the odours, whereas population panels and questionnaires also give direct information about the degree of odour annoyance experienced by the residents.
All the future research work and mentioned above is related to the fields of air pollution or occupational exposure research. All these industrial plants represent a subject of many other fascinating research work in the other fields of “Green Chemistry” (204), for example sewage treatment studies, hazardous waste management, the use of landfills, recycling, and the use of so called BAT-techniques (205). In addition, the suitability of direct-reading instruments, e.g. field-portable X-ray fluorescence analysers, should be evaluated in obtaining information about the composition of mining samples, as well as for the determination of heavy metals in glass fibre filters.