ABSTRACT
Urban trees are a new tool for pollutant monitoring since gaseous and particulate pollutants can deposit in its barks. Polycyclic aromatic hydrocarbons (PAHs) levels were determined in gaseous phase samples collected in polyurethane foam (PUF), total suspended particles (TSP) samples collected in quartz fiber filters and tree bark samples (Tipuana and Sibipiruna) collected in the surroundings of an industrial complex in the metropolitan area of São Paulo. Benzo(b)fluoranthene presented the highest average concentration in the TSP samples and phenanthrene, the highest average concentration in the PUF samples; the sum of carcinogenic equivalents for benzo(a)pyrene (BaPEq) for both phases was above 20â¯ngâ¯m-3, representing a high cancer risk. The most abundant PAH for tree barks was fluoranthene; low weight PAHs presented a higher abundance than the observed in TSP. Coronene (vehicular exhaust marker) presented good correlations with fluoranthene in the tree bark samples, suggesting an influence of vehicular emissions. A tree bark sample collected near the petrochemical area presented biomarkers of petrogenic origin (hopanoids) in the mass spectrum and an unresolved complex mixture (UCM) profile. The results suggested an influence of both vehicular and industrial sources on the air quality observed in the atmosphere and tree barks samples.
