Published 01 Dec 2004
Last modified 13 Apr 2011, 07:17 PM
Celebrations were held on 1 Dec 2004 in Geneva to mark the 25th anniversary of the convention on long-range transboundary air pollution (CLRTAP).
Coordinated by the UN economic commission for Europe (Unece), the treaty is credited with significantly cutting acidifying pollutants such as sulphur dioxide and nitrogen
oxides. It now extends to ozone, heavy metals and persistent organic pollutants (POPs).