Automotive emissions of polycyclic aromatic hydrocarbons
The International Agency for Research on Cancer (IARC) has classified certain individual polycyclic aromatic hydrocarbons (PAH) as carcinogenic to animals and probably carcinogenic to humans. Current PAH concentrations in European ambient air are the lowest ever measured, largely as a result of the reduced use of coal in domestic and other heating. Nevertheless, in 1999 the European Commission created a Working Group to review the knowledge on PAH in ambient air and to consider the need for, and implications of, regulations on the concentrations of PAH under the Air Quality Framework Directive (96/62/EC). Amongst the EU Member States, only Italy currently has legally enforceable ambient air standards for PAH but five others have issued guidance for planning and policy purposes, all based on the use of benzo(a)pyrene (B[a]P) as a marker for PAH. Road transport is a relatively small contributor to B[a]P emissions. By 2010, domestic combustion of solid fuels, in particular wood, is expected to be by far the largest contributor to total European B[a]P emissions.