Journal of Environmental Protection, 2015, 6, 25-33 Published Online January 2015 in SciRes. http://www.scirp.org/journal/jep http://dx.doi.org/10.4236/jep.2015.61004 How to cite this paper: Canales-Rodríguez, M., et al. (2015) Distribution and Characterization of PM 10 in City and Valley of Mexicali, Baja California, Mexico. Journal of Environmental Protection, 6, 25-33. http://dx.doi.org/10.4236/jep.2015.61004 Distribution and Characterization of PM 10 in City and Valley of Mexicali, Baja California, Mexico Miguel Canales-Rodríguez 1* , Margarito Quintero-Núñez 1 , Benjamin Valdés-Salas 1 , Walter Daessle-Heuser 2 1 Departament of Environment, Institute of Engineering, Autonomous University of Baja California, Mexicali, México 2 Deparment of Environmental Geosciences, Institute of Oceanological Research, Autonomous University of Baja California, Ensenada, Mexico Email: * miguelcanales13@hotmail.com , maquinu@uabc.edu.mx , benval@uabc.edu.mx , walter@uabc.edu.mx Received 19 December 2014; accepted 1 January 2015; published 14 January 2015 Copyright © 2015 by authors and Scientific Research Publishing Inc. This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/ Abstract The variability of the levels of atmospheric particulate matter PM10 and its composition is as- sessed in the rural and urban zones of Mexicali during fall and winter 2008-2009, using a low level volume Minivol sampler, with quartz and Teflon filters. During fall the Mexican norm was ex- ceeded (120 μg/m 3 in 24 hr) in only two occasions, while in winter it was exceeded twelve times. The predominant component in fall was geological material with 62.5% for the rural zone and 48.5% for the urban one. In winter the geological material was also predominant with 65% for the rural zone and 54.4% for the urban zone. The aim of this work is the interpretation of the varia- bility of the atmospheric PM10 particulate matter at two selected zones (urban and rural of Mexi- cali) during fall and winter, with emphasis on the chemical composition. The results suggest that the pollution in the urban and rural zones has common sources during winter whereas in fall the pollution has different sources. Keywords Urban, Rural, Atmosphere, Particulate Matter 1. Introduction The battle against air pollution began since the invention of the steam machine and with that the industrialization * Corresponding author.