Temporal variations in elemental concentrations of atmospheric aerosols in Mexico City

Abstract

Measurements are reported of elemental concentrations of airborne particulates in Mexico City and their time variation over a one-week period in the spring of 1988. Proton-induced X-ray emission analysis (PIXE) was used to analyse the atmospheric aerosols which were bombarded with 2.5 MeV protons from the 12 MV tandem Van de Graaff accelerator at the Instituto Nacional de Investigaciones Nucleares, ININ. Variations in the elemental concentrations were observed over the time period studied. An intercomparison was made in the case of the element lead with PIXE results obtained at the Crocker Nuclear Laboratory (CNL), University of California for the same set of samples. Excellent agreement was obtained both for the time variation of the relative concentration and the absolute lead concentrations. These results give added confidence to the protocol adopted at ININ. © 1993.