Polycyclic Aromatic Hydrocarbons

Other names


CAS Number



  • group of chemically similar substances, all of which consist of a number of aromatic rings (benzene rings)
  • PAH group: list of the 16 priority PAHs defined by the United States Environmental Protection Agency
  • crystalline solids
  • colour and odour vary according to substance

Main sources

  • combustion of coal, mineral oil, wood
  • tobacco smoke
  • washed out from tar (frequently used to pave roads and cover roofs until the 1970s)
  • only a few substances are used for industrial purposes

Thresholds for the reporting requirement of facilities in accordance with Annex 2 PRTRO

(Ordinance on the Register relating to Pollutant Release and the Transfer of Waste and of Pollutants in Waste Water)

  • Air               50 kg/year
  • Water          5 kg/year
  • Soil              5 kg/year


  • vary according to substance
  • Benzo(a)pyrene: carcinogenic
  • other PAHs: suspected carcinogenic effect

    Last modification 16.12.2016

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