Particulate Matter in Ambient Air

Numerous studies have demonstrated the negative effect of particulate matter on human health. The EU therefore introduced ambitious limit values for particulate matter (PM10) in ambient air as early as 1999: an annual limit and a daily limit that can be exceeded on up to 35 days a year. These values are binding since 2005. The daily limit is still exceeded in many cities throughout Europe. Heated debates on the future of the daily limit are taking place at all levels of the EU in the context of the negotiations on the Commission's proposal on a new Air Quality Directive. Suggestions range from allowing a compliance time extension to increasing the number of days the daily limit can be exceeded, and abolition of the daily limit value. The deliberations have not yet been concluded, but the decisive European institutions have voiced support for keeping the daily limit while at the same time extending the compliance deadline. In this article, we will make the point that the problem can most probably be solved by allowing a compliance extension of around 5 years after the new directive enters into force. This would give the competent local authorities and the EU the time necessary to intensify their measures in order to comply with the daily limit in most areas where it is currently exceeded. An increase in the number of days the limit values may be exceeded, as called for by the European Parliament (EP), would therefore amount to an unnecessary lowering of the limit value.