When adopting regional plans aimed at improving air quality, environmental authorities are often faced with the relevant costs that the adoption of abatement measures implies. On the other hand, scientific literature has well documented damages due to air pollution impact on human health and ecosystems. This paper proposes a tool that allows balancing these two viewpoints by defining the efficient set of measures in a multi-objective perspective. Despite both external (health related) and internal (industrial/emission abatement related) costs can be measured in the same unit, namely money, it appears unacceptable to add them together as in a cost-benefit analysis, since they pertain to quite different social groups. The tool proposed in this paper can thus be seen as a support to actual decision makers and allows them to compare in a ponderable way the pros and cons of any abatement policy. This contrasts what normally happens when air quality health impacts are simply defined as the satisfaction of a constraint at few specific points in space (coincident with the presence of measurement gauges). Indeed, both population and ecosystems are distributed in a non-uniform way on a territory and thus sparse point measurements of pollutant concentrations or other related air quality indicators may be only loosely related with the real impacts of air quality. An application of the tool to a European region (Lombardy, Italy) is presented with particular reference to PM10 and Ozone pollution problems. These are particularly difficult to cope with, since these pollutants are mainly formed in the atmosphere (secondary pollutants) and thus their concentration depends on chemical physical processes involving in different way on one side the emission of precursors and, on the other, the local meteorological conditions.