Air pollution - Drivers and pressures (Italy)

The emission reductions of PM₁₀ (30 %, and especially marked in the energy and industrial sectors), of nitrogen oxides (NO_X 43 %) and of non-methane volatile organic compounds (NMVOC 41 %) registered between 1990 and 2006 (APAT Emissions Inventory) have led to a clear improvement in air quality, but do not resolve problems related to PM₁₀, NO_X and O₃, thus confirming the complexity of the problem of air pollution, which calls not for emergency measures but long-term integrated initiatives.

In the case of PM₁₀, with regard only to its primary component, the information provided by APAT in the National Emissions Inventory for 2006 shows that transport is the main source of pollution, accounting for 41 % of the total, of which approximately two-thirds is attributable to roadway transport; next comes industry (25 %), the residential sector (13 %) and agriculture (10 %).

In terms of the precursors of tropospheric ozone, the main source of nitrogen oxide emissions (NOx) is transport which accounts for 65 %, with road transport representing more than two-thirds, industry is responsible for 15 %, the production of energy for 11 % and the residential sector for 9 %. As for volatile organic compounds, but solely with regard to the non-methane ones (NMVOC), transport is responsible for 39 %, while 42 % come from the use of solvents, and the rest from the industrial sector, the residential sector and other minor sectors. Emissions of both tropospheric ozone precursors and PM₁₀ have fallen considerably in all the regions, with the magnitude of the decrease depending on the presence of large-scale industrial plants, for which stringent limits were introduced in the 1990s on smokestack emissions of SO_x, NO_x and PM₁₀. In fact, emissions of these substances from industrial combustion and energy production plants have dropped significantly between 1990 and the present.

The points briefly illustrated indicate that transport, and especially by road, is one of the main causes of the high concentrations of PM₁₀ and ozone in the air. This critical problem is especially acute in cities where the levels of population and transport density are highest. In urban settings, emissions from road transport account for more than 70 % of overall emissions of PM₁₀, NO_x and NMVOC. (http://annuario.apat.it/capitoli/Ver_6/en/Air%20quality.pdf - Paragraph ‘The main causes of air quality deterioration’, pg 88)