Asphalt fume dermal carcinogenicity potential: II. Initiation-promotion assay of Type III built-up roofing asphalt

► Field matched fume condensate from oxidized Type III built up roofing asphalt was tested for tumor initiation and promotion. ► After 6 months of study, evidence of tumor initiation, but not tumor promotion was observed in mouse skin. ► These results suggest a mechanism of action that includes genotoxicity. ► Compared to polycyclic aromatic hydrocarbons, field-matched fume has a relatively weak potency.