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The soiling of the external façades of buildings caused by air pollution has economic costs that are generally not borne entirely by the polluters but by society in general. The present paper attempts to estimate the maintenance costs attributable to the soiling of the façades of residential buildings exposed to ambient air pollution in Italy. In this study, dose-response functions were used to link the environmental concentrations of pollutants to the soiling rate of the opaque and transparent surfaces of the building façades. It was assumed that the spatial distribution of façade materials follows the distribution of population. The basic assumption was that maintenance is performed when critical levels, 35% loss of reflectance for opaque surfaces and 1% haze for glass surfaces, are reached. Several important elements seem to emerge from the analysis carried out. The cost of damage to opaque surfaces due to air pollution appears to be a non-negligible fraction of the total maintenance costs of building façades incurred in Italy. Moreover, the cost of soiling damage to residential buildings from particulate matter has the potential to significantly increase total external costs due to air pollution. The costs of cleaning window panes due to air pollution also appear significant. Finally, if the levels of atmospheric pollution in the most populated areas become similar to the concentrations currently present in the most remote areas in Italy, the overall cost at national level due to the soiling of the building façades could be reduced by about 50%.

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Air pollution, particularly in urban areas, is a concern for its negative effects on the materials of the built environment. Cities are also home to a large part of our cultural heritage. Air pollution accelerates the natural processes of deterioration of the materials of historic buildings and monuments, causing premature aging and reducing their aesthetic value. The present paper aims to assess the current potential damage due to air pollution on different materials through Europe. Several corrosion and soiling maps were produced by applying widely used dose-response functions. One of the priorities of this study was to provide an estimate of the effects of air pollution on UNESCO World Heritage cultural sites throughout Europe. The potential risk for cultural heritage monuments was estimated on the basis of exceeding tolerable degradation thresholds suggested for each material. The results show that, despite the significant improvements in air quality in Europe over the past few decades, air pollution is still considerable and continues to be an important agent of degradation of cultural heritage, particularly in anthropized areas. Although the methodology used in this study provides a simplified assessment of the likelihood of damage to UNESCO's cultural heritage in Europe from air pollution, it provides a unique perspective and the potential risk is assessed on a common basis. The results obtained contribute to a better understanding of the existing risk deriving from atmospheric pollution and to highlighting those sites, generally located in areas where anthropogenic activity is relevant, that need particular attention. The present paper can serve as a basis for stimulating additional studies and site-specific analyzes, as well as highlighting the need for further measures and policies for atmospheric pollution reduction in cities and in the surroundings of sensitive historic buildings and monuments to prevent further damage.

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This study investigated the contribution of unburned lubricating oil and gasoline-derived n-alkanes to particulate emission from non-catalyst and catalyst-equipped two-stroke (2-S) mopeds operated with ester-based, fully synthetic lubricating oil. Exhaust particulate matter (PM) from ten 2-S, 50 cm3 mopeds belonging to three different levels of emission legislation (EURO-0, EURO-1 and EURO-2) was collected during the sampling phase of the ECE 47 driving cycle through which each mopeds was driven on a dynamometer bench. Filters containing PM were extracted with an accelerated solvent extractor and analysed by gas-chromatography/mass spectrometry. The contribution of unburned lubricating oil to the PM was ascertained and quantified by exploiting characteristic ions in its mass spectrum. The experimental results show that unburned lubricating oil accounted for a significant fraction (4.7-38.7%) of the PM emitted from 2-S mopeds. Emission rates of particulate unburned lubricating oil and n-alkanes from non-catalyst EURO-0 mopeds were 15.4-56.2 mg km(-1) and 1-2 mg km(-1), respectively. These emission rates were reduced of 75% and 88%, respectively, for catalyst-equipped EURO-1 mopeds. The results of the tests carried out on two EURO-2 mopeds of different technology were contrasting. A EURO-2 moped with carburettor and secondary air injection exhibited a clear reduction of 95% and 88% for unburned lubricating oil and n-alkanes emission rates with respect to the average values observed for EURO-1 mopeds. On the other hand, the second EURO-2 moped, equipped with catalyst and direct injection, had unburned lubricating oil emission rates roughly in the range of EURO-0 mopeds while particulate n-alkanes were emitted at rates comparable with typical values observed for catalyst EURO-1 mopeds.

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The emissions of particle-phase polycyclic aromatic hydrocarbons (PAHs) were evaluated in the exhaust of four (two EURO-0 and two EURO-1) four-stroke engine, in-use scooters with displacement of 150 cc, which were not equipped with catalytic converters. Non-catalysed motorcycles still represent a large proportion of circulating two-wheelers in Italy and, possibly, also in other countries. Tests were performed on a dynamometer bench, using the ECE-40 test cycle procedure. Particulate matter into the exhaust emissions was collected both during the "hot" phase of the ECE-40 driving cycle and including the first two elementary cycles of engine warming-up heating (whole cycle). Fourteen PAHs were quantified and total PAH emission factors (Sigma PAH) ranged from 7 to 169 microg km(-1). Expressed in benzo(a)pyrene equivalent (BaP(eq)), emission factors ranged from 0.6 to 18 microg km(-1). Results from the tested scooters show that despite their small engine size, non-catalysed motorcycles can emit amounts of particulate PAHs that can be comparable or even higher than emissions reported elsewhere from gasoline- and diesel-powered passenger cars and light- and heavy-duty vehicles. In countries where a large number of non-catalysed motorcycles are circulating, PAH emissions in urban areas from this class of vehicles might be of the same order of magnitude of emissions from diesel passenger cars.

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The association of radiocaesium with particle size fractions separated by sieving and settling from soils sampled eight years after the Chernobyl accident has been determined. The three size fractions were: <2 microm, 2-63 microm and >63 microm. 137Cs in the soil samples was associated essentially with the finer size fractions, which generally showed specific activities 3-5 times higher than the bulk samples. Activity ratios of 134Cs/137Cs in the clay-sized fractions appear to be lower with respect to the corresponding values in bulk soil samples. This result indicates that some differences still exists in the particle size distribution between 137Cs originating from nuclear weapons, which has been in the soil for decades after fallout, and 137Cs coming from the Chernobyl accident, eight years after the deposition event. This behaviour could be related to "ageing" processes of radiocaesium in soils.

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