PAHs (polycyclic aromatic hydrocarbons) are a large group of organic compounds made up of two or more aromatic rings of carbon and hydrogen. The present emission inventory includes the four PAHs reported to UNECE: benzo(a)pyrene, benzo(b)-fluoranthene, benzo(k)fluoranthene and indeno(1,2,3-cd)pyrene. The most important source of PAH emissions is combustion of wood in the residential sector. Correspondingly, the increasing emission trend is due to increasing combustion of wood in the residential sector.

PAH occur in two forms; as gas and adsorbed on particles. PAHs are toxic compounds and especially particulate PAHs are potentially carcinogenic. Benzo(a)pyren (BaP) was one of the first known carcinogen compound. It is the best examined and one of the most toxic PAHs classified as “probably carcinogenic to humans” according to the IARC classification. It is not possible to find a lower concentration limit under which PAHs are not associated with a health risk. For further information in PAHs please refer to the book “Tjærestoffer” (in Danish). 

(Click the chart to view background data)

 (Clic the chart to view background data)