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Home Topics Chemicals & Poisons Compendium of Chemical Hazards Polycyclic aromatic hydrocarbons

Polycyclic aromatic hydrocarbons

Key Points



  • The term polycyclic aromatic hydrocarbons (PAHs) refers to a group of several hundred chemically-related environmentally persistent organic compounds of various structures and varied toxicity
  • Benzo[a]pyrene (BaP) is commonly used as an indicator species for PAH contamination and most of the available data refer to this compound



  • May react violently with oxidising agents
  • Emits toxic and irritating fumes on decomposition
  • In the event of fire involving PAHs, use fine water spray and liquid tight chemical protective equipment



  • Toxic by inhalation, ingestion or skin absorption
  • Carcinogen, mutagen and reproductive toxin
  • Long-term inhalation can cause a decrease in lung function, chest pain and irritation
  • Long-term skin contact can cause dermatitis and warts
  • BaP is thought to probably cause lung and skin cancer in humans



  • Environmentally hazardous substance
  • Inform Environment Agency of substantial incidents

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Compendium of Chemical Hazards