The available data does, however, suggest that present PM10 values exceed the recommended limit values in the majority of Member States. In future projections, planned actions should be taken into consideration. These include the SOx and NOx Protocols within UNECE and the Auto-Oil programme. Abatement policies for other pollutants will also have an impact. Actual reductions are, though, likely to be difficult to predict and not necessarily linearly related to emission reductions because of formation rates for secondary aerosols, which are in turn dependent on concentrations of other species in the air. Thus, abatement strategies have to be developed if the currently planned precautions.
