This Thesis presents the results of various studies on peat soils and organic surface horizons of peaty podzols derived from acidification-sensitive parent materials. It aims primarily at finding out which peat and organic surface horizon chemical properties correlate most significantly with acidifying deposition parameters, the effect that acidifying pollutant deposition has on growth of vegetation (<I>Calluna vulgaris</I>) and litter decomposition, and the fate of ammonia in peat soils. Two regional surveys were carried out throughout Scotland. Significant correlations were found particularly between the chemical properties of peat and the effective concentrations of the acidifying deposition components. The more significant correlations found with peat pH(water), rather than with pH(CaCl₂), point to the fact that the mobile anion effect is important. A method was established for estimating the pH of soil solution at field conditions, <I>i.e.</I> at a dilution factor of unity, and a close similarity was subsequently found between this estimated pH and the effective pH of deposition. It is suggested that this provides an excellent basis for pH prediction for ombrotrophic peats. Significant seasonal variations in peat chemistry were found, with peat pH(water), for example, varying by up to 0.4 pH units throughout the year. A 7-month pot experiment demonstrated significantly lower growth rates of <I>Calluna vulgaris</I>, and slower litter decomposition rates, at higher acidifying deposition inputs. Studies on the retention of NH₄⁺ in peats clearly show that there is only a limited capacity for biological immobilisation of NH₄⁺ at high input concentrations. More information is needed on the fate of NH₄⁺ inputs in the soil, and on the extent to which retention is via cation exchange and biological uptake, and this needs to be taken into consideration when setting critical loads for N.

An analytical method was developed for the experimental investigations. This included sampling, separation into fractions, clean-up and determination of the organochlorines in suspended solids and seawater. A sampling apparatus was designed and built in our laboratory, capable of sampling seawater up to 28 l, and separating the suspended particles prior to the extraction of the filtered water with organic solvent. The analytical method for the determination of chlorinated biphenyls (CBs) and a large number of organochlorine pesticides in sediments was readily available in our laboratory. In addition, a method for the determination of pentachlorophenol (PCP) in seawater and solids was developed. The complete analytical method for the determination of particulate and dissolved organochlorines in the seawater column, at the ng l^-1-pg l^-1 level, was validated. Small scale experiments were not able to replicate the environment, therefore, a large scale experiment was undertaken in a Loch in the NW of Scotland. Experimental bags, 60,000 l capacity, were attached to a floatable frame and filled with seawater, then contaminated sewage sludge was dumped on it. A sampling strategy was designed, and a set of samples was obtained to investigate the factors affecting the partitioning, and the kinetics of the partitioning, between suspended solids and seawater. The experimental data from the analysis of the samples were used to propose a simple mathematical model describing the changes in the concentrations of particulate and dissolved organochlorines over the time of the experiment. The mathematical modelling provided values for the desorption rates and the partition coefficients of the nonequilibrium for the individual organochlorines. These calculated parameters were used to elucidate the possible trends related to physico-chemical properties of the organochlorines, and to propose the process affecting the organochlorine-particle interactions: intra-organic matter diffusion.

No description available.

No description available.

No description available.

No description available.

No description available.

No description available.

The purpose of this study was to examine the school environment in the municipalities of Malå and Norsjö. The study focused on cleaning, ventilation, classroom noise and illumination which are the most important factors for a good indoor climate and a good working environment in school. The study was performed by inspection of school buildings, questionnaire among school children and measurements of CO2. The result showed that all the visited schools did not meet the Swedish standards for cleaning and ventilation, also sound environment and the illumination had inadequacies in some of the classes. The result also showed that the majority of the pupils were satisfied with the indoor climate and working environment. Of the total percentage of pupils surveyed, 35% of the pupils were unsatisfied with the cleanliness of the toilets and 44% reported that the sound level is perceived as disturbing. The measurements of CO2 showed that all schools had concentrations (ranging from 541-926 ppm) below the Swedish standard (1 000 ppm), nevertheless there was indications that these concentrations may increase during a day. In conclusion this study showed that the indoor environment in the visited schools had inadequacies which may have a negative impact of the pupils. To avoid unhealthy, and from a public health perspective, these inadequacies should be attended.

Background Particulate matter (PM) air pollution is associated with increased respiratory and cardiovascular morbidity and mortality. Diesel engine exhaust (DE) and wood combustion are major contributors to ambient air pollution and adverse health effects. The aim of this thesis was to investigate the fate of inhaled combustion-derived PM, the subsequent effects on pulmonary inflammation and symptomatology and to explore the potential for particle filters to improve public health. Additionally, it aimed at increasing the understanding of the pathophysiological mechanisms underlying the adverse vascular effects of PM inhalation in man. Methods In study I, lung deposition of wood smoke-derived particulates from incomplete combustion was determined in healthy and COPD subjects. In study II, airway inflammation was assessed in healthy subjects exposed to wood smoke and filtered air. In study III, vehicle cabin air inlet filters were evaluated regarding filtering capacity for DE and whether they affected the toxicological potential of the filtered PM. Healthy subjects were then exposed to filtered air and unfiltered DE, as well as DE filtered through two selected filters. In study IV, healthy subjects were exposed to filtered air and DE. Nitric oxide bioavailability was assessed by plethysmography in the presence of an NO clamp (NO synthase inhibitor NG-monomethyl locally and systemically administered) with measurements of arterial stiffness, cardiac output and blood pressure (BP). Results Study I: The total PM number deposition fraction of the wood smoke was 0.32 and 0.35 for healthy and COPD subjects respectively. Study II: Inhalation of wood smoke caused CD3+ and mast cell infiltration in the bronchial submucosa along with CD8+ cell recruitment to the epithelium. In bronchial wash, inflammatory cells, myeloperoxidase and matrix metalloproteinase 9 levels decreased. Study III: An efficient cabin air filter with an active charcoal component was most favourable in in-vitro tests and reduced symptoms in the human exposure study. Study IV: Local NO synthase inhibition caused similar vasoconstriction after exposure to DE and filtered air, along with an increase in plasma nitrate concentrations, suggesting an increase in the basal NO release due to oxidative stress. Systemic NO synthase inhibition increased arterial stiffness and blood pressure after DE exposure along with an increase in systemic vascular resistance and reduced cardiac output, implying that the increased basal NO release could not compensate for the reduced NO bioavailability in the conduit vessels. Conclusion Wood smoke particles from incomplete combustion tend to have a greater airway deposition than particles from better combustion. The airway inflammatory responses to the former particles differ from what have been shown for other PM pollutants, which may be of importance for subsequent health effects. The vasomotor dysfunction shown after DE exposure may largely be explained by reduced NO bioavailability. A vehicle cabin air inlet particle filter with active charcoal was effective to reduce DE exposure and subsequent symptoms. This may conceptually be of benefit when it comes to decreasing engine exhaust-related adverse health effects.