title: Tracking polycyclic aromatic hydrocarbons in lichens: It's all about the algae.
abstract: Lichens, symbioses of fungi and algae and/or cyanobacteria, have the remarkable ability to uptake and accumulate semivolatile organic compounds (SVOC) from air, including polycyclic aromatic hydrocarbons (PAHs), but the mechanism of accumulation is still unknown. Understanding these mechanisms is critical to standardize the use of lichens as environmental bioindicators and to further integrate them in air monitoring networks. Through a series of experiments we show that gas phase PAHs easily cross lichen's surface and accumulate in the photosynthetic algal layer of lichens. Once accumulated, they remain in the algal layer and not within the fungus hyphae, or adhered to lichen's surface, as it was previously supposed to happen. Additionally, when lichens are washed, gas phase PAHs still remain in the algal layer. Our results reveal that lichens may be utilized as bioindicators of gas phase PAHs, overcoming current limitations of air monitoring.
authors: TECNATOX, Chemical Engineering Department, Universitat Rovira i Virgili, C/ Països Catalans, nº 26, 43007 Tarragona, Spain; cE3c-Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, Bloco C2, Piso 5, 1749-016 Lisboa, Portugal. Electronic address: anasofia.pachecomarques@urv.cat.
authors: Sofia
authors: S
authors: Augusto
authors: TECNATOX, Chemical Engineering Department, Universitat Rovira i Virgili, C/ Països Catalans, nº 26, 43007 Tarragona, Spain; Laboratori d'edafologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII s/n, 08028, Barcelona, Spain.
authors: Jordi
authors: J
authors: Sierra
authors: Laboratory of Toxicology and Environmental Health, School of Medicine, IISPV, Universitat Rovira I Virgili, Sant Llorenç 21, 43201 Reus, Spain.
authors: Martí
authors: M
authors: Nadal
authors: TECNATOX, Chemical Engineering Department, Universitat Rovira i Virgili, C/ Països Catalans, nº 26, 43007 Tarragona, Spain.
authors: Marta
authors: M
authors: Schuhmacher
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000460:Chlorophyta / Q000737:chemistry*; D004784:Environmental Monitoring / Q000379:methods*; D008011:Lichens / Q000737:chemistry*; D008856:Microscopy, Fluorescence; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis* / Q000493:pharmacokinetics; D055549:Volatile Organic Compounds / Q000032:analysis* / Q000493:pharmacokinetics
chemical_list: D000393:Air Pollutants; D011084:Polycyclic Aromatic Hydrocarbons; D055549:Volatile Organic Compounds
keywords: Air pollution; Benzo[a]pyrene; Fluoranthene; Xanthoria parietina