Determination of Trace Elements in Liquid Fuels by Instrumental Neutron Activation Analysis

Monitoring Air Quality with Transplanted Bryophytes in a Neotropical Andean City

Air pollution is one of the main global environmental problems, where bryophytes, due to their high capacity to retain metals and other pollutants, have been widely used in active air quality monitoring studies in temperate and tropical zones. Thus, in this study, we analyzed for the first time the concentrations of eight metals (cadmium, copper, nickel, aluminum, iron, manganese, lead and zinc) in three species of transplanted mosses (Rhacocarpus purpurascens (Brid.) Paris, Sphagnum sp. and Thuidium delicatulum (Hedw.) Schimp.) from Ecuador. Significant differences were found for the three species in the concentrations of Al, Mn, Fe and Zn between urban and control areas, pointing to the Central zone as the main source of contamination with the highest concentrations of Al, Fe, Mn and Zn, related to vehicular traffic. Lead did not differ between zones for Rhacocarpus purpurascens and Sphagnum sp.; however, Thuidium delicatulum accumulated different concentrations between urban areas and the control areas. The three species of mosses provided valuable information on the contamination of Al, Fe, Mn, Pb and Zn in the urban area of the city of Loja, and therefore can be used in future air quality monitoring programs over time in tropical cities.