Nitrogen dioxide is a pollutant gas involved in many different chemical processes in the atmosphere. In the troposphere, it acts as a photocatalyst in a series of oxidation reactions of volatile organic compounds (VOCs), generating ozone and low molecular weight aldehydes [1]. In addition, NO2 is a precursor in the formation of nitric acid, which participates in the formation of aerosols that can affect human health and modify cloud formation processes [2]. The deposition of NO2 and HNO3 can modify the acidity of soils and waters, as well as increase the availability of nitrogen as a macronutrient [3]. Determination of the concentration of NO2 can be used to estimate deposition of the main reactive nitrogen species to soil and water [4].