In most countries in the region covered by the United Nations Economic Commission for
Europe (UNECE), ambient air quality has improved considerably in the last few decades. This
has been achieved by a range of measures to reduce harmful air emissions, including those
stipulated by the various protocols under the Convention on Long-range Transboundary
Air Pollution (1). There is, however, convincing evidence that current levels of air pollution
still pose a considerable risk to the environment and to human health.

Recently, the Executive Body of the Convention has adopted amendments to the
Convention’s 1999 Gothenburg Protocol to Abate Acidification, Eutrophication and Groundlevel
Ozone. Following years of negotiations, the approved revised text of the Protocol now
specifies national emission reduction commitments for main air pollutants to be achieved
by the UNECE Parties by 2020 and beyond. The revised Protocol includes, for the first time,
commitments to reduce the emission of fine particulate matter (PM2.5). Furthermore, black
carbon or soot is now included in the revision as an important component of PM2.5. Black
carbon is an air pollutant which both affects health and contributes to climate change (2). And for anyone who cares: