Table 2 Molecular effects of PAHs induced by the parent compounds, reactive oxygen species (ROS) and electrophilic metabolites

Cellular induced ROS formation/oxidative stress

 Redox cycling of eg PAH-metabolites

 Activation of membrane bound oxidases

 Damage to mitochondria

 Activation of ROS defense (macrophages)

Membrane receptors, transporters and channels e.g. β₂-AR

 Ca²⁺ signaling

 cAMP signaling

 Phosphorylation signalling (including inhibition of phosphatases)

Intracellular receptors including aryl hydrocarbon receptor (AhR)

 Classical genomic: CYP enzymes

 Non-classical genomic: cross talk with e.g. NF-κB

 Non-genomic signalling:

  Protein phosphorylation via kinases (ScC)

  Membrane order/caveola

  Ca²⁺ signaling

Genotoxic effects

 DNA damage and epigenetic changes