Size matters: the very tiny particles in the air

12/12/2017 23:40

Particulate matter (PM) in the ambient air is a complex mixture of particles of different sizes and chemical composition. Ultrafine particles (UFP) are those very tiny particles defined by having a size below 0.1 µm (that is, below 100 nanometres) in diameter. Contrary to larger particle definitions, such as PM2.5 and PM10 (particles with a diameter below 2.5 and 10 µm, respectively; Figure 1), UFP are not regulated and, therefore, there is no limit value for the local and regional administrations to meet. However, many studies suggest that UFP might pose a higher threat to human health than

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Exposure to air pollutants during commuting

07/03/2017 01:00

Nowadays it is well known that air pollution supposes a major threat to human health (GBD 2013 Risk Factor Collaborators, 2015). The pollutants emitted by combustion sources, such as traffic emissions (Figure 1), are suspected to be particularly harmful (HEI Panel on the Health Effects of Traffic-Related Air Pollution, 2010). Black Carbon (BC) and ultrafine particles (UFP, particles with an aerodynamic diameter <100nm) are much better tracers of traffic emissions than particulate matter of <10µm (PM10) or <2.5µm (PM2.5; the latter two, being regulated by the UE legislation). In fact,

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When and where are we more exposed to air pollution? The personal exposure assessments

07/06/2016 05:00

Traditionally, the exposure of the population to air pollutants has been assessed based on data from air quality monitoring stations located all across the country (in Catalonia we have the XPVCA, http://dtes.gencat.cat/icqa), which provide data for a variety of pollutants, but only in few points in a city or region. However, according to the definition of Ott (1982), human exposure is ‘the event when a person comes into contact with a pollutant of a certain concentration during a certain period of time’. Therefore, for an accurate personal exposure assessment the different places in which

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