Monitoring of elements in mosses by instrumental neutron activation analysis and total X-ray fluorescence spectrometry

Abstract

This research presents a study of environmental monitoring at different sampling sites from the Metropolitan Area of the Valley of Toluca (MAVT) Mexico by means of moss samples. The selected sampling sites included urban, transitional and natural protected areas. The mosses were obtained in two campaigns within two periods of the year: rainy-season and dry-cold-season. During the sampling, seven species of moss were identified, among them: Leskea angustata (Tayl.) and Fabronia ciliaris (Brid.) were the most abundant. One sample of each species was analyzed by SEM in order to determine their morphology. After that, the samples were analyzed by instrumental neutron activation analysis (INAA) and total X-ray fluorescence spectrometry (TXRFS) in order to determine the metals concentration. The results indicate that the Urban Region was significantly impacted by pollution compared to the natural protected Areas. The cluster statistical analysis results indicated that the sampling sites with the highest concentration of metals are located in the urban areas. Enrichment factors show that As, Cr, Cu, Zn, Pb, Se, Cs, and Sb are highly enriched mainly by anthropogenic sources.