PARTICLE POLLUTION AND THE ROLE OF ECOLOGICAL INDICATORS FOR THE PREVENTIVE CONSERVATION OF CULTURAL HERITAGE

MARCOS A.E. CHAPARRO; DÉBORA C. MARIÉ ; DANIELA BUITRAGO POSADA ; ALDO WINKLER ; MARCOS TASCON ; LISA GRIFONI; MARTINA SCOCCIMARRO; FEDERICO CHERNY; FERNANDO MARTE; L. PENSABENE BUEMI; FRANCESCA BOLDRIGHINI; A. RUSSO; GABRIELLA STRANO; LUIGI A. DI LELLA; LILLA SPAGNUOLO; STEFANO LOPPI; ANTONIO SGAMELLOTTI

Malargue

Congreso; 18° Encuentro del Centro Internacional de Ciencias de la Tierra (E-ICES 18); 2023

ICES

Anthropogenic particle pollution is an increasing concern in urban contexts because itmay adversely influence citizens' cultural heritage (CH), such as museums,archaeological sites, and historic buildings. Among adverse consequences of particulatematter (PM) on CH institutions, it may act on the surfaces, creating dark layers,abrasion of materials, depletion, discoloration, and consequent artistic loss. The latterhas recently been studied using magnetic biomonitoring in various Italian institutionsand urban archaeological sites, including Villa Farnesina in Rome, the PeggyGuggenheim Collection in Venice, and the Palatino Hill of Parco Archeologico delColosseo. We present here the first magnetic biomonitoring study in Argentina focusedon the preventive conservation of the collections preserved at the Museo Nacional deBellas Artes (MNBA) and the Museo Histórico Nacional (MHN) in Buenos Aires.Thalli of lichen species (Parmotrema pilosum) were collected at remote sites andtransplanted to indoor and outdoor sites for three months. In addition, for biomonitoringpurposes, leaves from urban trees (Jacaranda mimosifolia and Fraxinus excelsior) werecollected at increasing distances from MNBA and MHN, respectively. The magneticproperties of lichens and leaves were determined in situ and at the laboratory throughthe following measurements: magnetic susceptibility, anhysteretic, and isothermalremanent magnetization. Lichen transplants evidenced lower magnetic concentrationand finer grain size of trapped airborne magnetic particles (AMP) for indoor (AMPcontent = 20-140 μg) than outdoor (AMP content = 160-590 μg) sites, where magnetite-like minerals dominate (remanent coercivity H cr = 34.3-37.7 mT). Higher values ofmass-specific magnetic susceptibility χ were obtained for tree leaves of J. mimosifolia(χ = 13.1-50.4 ×10 -8 m 3 kg -1 ) than F. excelsior (χ = 0.6-7.5 ×10 -8 m 3 kg -1 ). Further magneticanalyses are ongoing on Evernia prunastri lichen transplants. Moreover, elementalanalysis of lichens and leaves will be conducted by ICP-MS to expand the informationregarding the origin and impact of the pollution.