Figure 3 . An action plan toolbox to prevent and mitigate air
pollution effects on childhood asthma
Industrial activities and traffic related air
pollution
The design of sustainable cities and the evolution of environmental
conditions are two of the main future challenges to strengthen urban
resilience and sustainably. One promising approach to achieve these
challenges is to implement nature-based solutions (NBS) in the
management and design of urban areas. NBS can provide several benefits
to cities and address different societal challenges, including air
pollution, while also contributing to restoring biodiversity, improving
human health, and thus supporting community wellbeing and livelihoods.
NBS, including indoor plants in living rooms and workplaces, trees in
streets and parks, green roofs and green walls, urban forests, and green
infrastructures, could be effectively implemented as an economic and
sustainable solution to reduce exposure to air pollution. Pollutants may
be removed from the atmosphere through wet and dry deposition on the
tree surface as in the case of particles, and/or by stomatal adsorption
and absorption processes in the case of gaseous pollutants. The
identification of specific plant species based on their air pollution
tolerance index, physiological characteristics, and habitat may be
helpful in the mitigation of air pollutants from different to a greater
extent. The BRIDGE project demonstrated that increasing canopy cover by
between 20% and 30% could improve PM10 removal in a range of 3% by
the year 2050 (www.bridge-fp7.eu). Recently, and within the framework of
the GreenInUrbs project, the “Specifind ” tool has been
developed to support NBS by allowing the selection of the best tree
species based on several parameters, including the improvement of air
quality (http://www.greeninurbs.com/p_specifind/).
The European Union (EU) has been making efforts to reduce pollutant
emissions from industrial sources, mostly by applying legal regulations,
such as the EU Emissions Trading System and the Industrial Emissions
Directive [79, 80]. Data submitted to the Convention on Long-range
Transboundary Air Pollution by the associated Nations, and published by
the European Environment Agency (EEA), shows that the concentrations of
industrial emissions have been tendentially decreasing since 1990
(Figure 4 ), suggesting that these regulations can indeed be
potential solutions to mitigate the effects of industrial pollution
[81].