TRACE METALS ELEMENTS DETERMINATION IN LICHENS FOR THE EVALUATION OF THE ATMOSPHERIC POLLUTION IN A REGION OF PERUVIAN ANDES

The study aims to assess the performance of epiphytic lichen Flavoparmelia caperata as an air pollution biomonitor. This lichen was used to evaluate air quality around the metropolitan area of Huancayo city (Junín, Peru). Ten sites with different land use and one non-contaminated site were chosen and twenty elements were measured (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Rb, Sb, Sr, Ti, V, and Zn) by ICP-MS analysis. This is the first study on the air quality and first kind of lichen used in this region. Cluster analysis (CA) and Enrichment Factor (EF) were applied to interpret the results. Higher concentration of all elements in sampling sites than control site was observed and EF values of Mn, Fe, Ba, Rb, Cr, Ni, Cu, Mg, and Sr, suggest that these elements may come not only of natural origin (soils) but also, by long transport phenomena, from other natural and/or anthropogenic activities, while EF > 10 suggest anthropogenic sources from vehicular emissions (Sb, Zn, Pb, Cd) and agricultural activities (As and Cd) as main sources. CA results discriminated the elements according to their sampling site resulting in three groups: urban, urban-rural and rural/control site and according variables were obtained two groups: Pb, Cu, Zn, As, and Sb related to anthropogenic sources, while natural sources represented by Cd, Mn, Fe, Ba, Cr, Ni, and Sr. Epiphyte F. caperata lichen occurred more frequently in the area, showed be efficient accumulator of toxic metals at low cost, and for future monitoring studies in this area