Evaluación de la calidad de aire mediante la aplicación de biomonitores en el Terminal Intercantonal de la Ciudad de Riobamba

Abstract

The aim of the current research was to analyze the air quality at the Intercounty Bus Terminal of Riobamba with the use of biomonitors, this is considered a high-flow traffic area since it has a direct bus gathering, these vehicles are considered a direct source for the emission of nitrogen dioxide and sulfur dioxide to the environment. First of all, it was proposed to determine what type of bryophyte is suitable to be used as biomonitor. This process was based on the direct injection of pollutants into five different types of bryophytes that were subsequently analyzed with a spectrophotometer. To verify the effectiveness of this air-quality valuation method, it was necessary to compare it with the traditional method that uses passive collectors. Both, the biomonitors and the passive sensors were set around the terminal in 25 specific points, this allowed obtaining quantitative data on pollutant concentrations in units of μg / m3. The analyzes carried out through UV-Visible spectroscopy evidenced that Metzgeriaceae species belonging to a class of liver moss is the one that best acts as a biomonitor due to its biosorption and bioaccumulation capacity. The final results confirmed that the level of pollutant concentration does not exceed the permissible limit established by the Ecuadorian law and the WHO (World Health Organization); thus, a maximum of 0.5602 μg / m3 of NO2 in one hour and a maximum of 10.2406 μg / m3 of SO2 in 24 hours were measured. It is concluded that the application of biomonitors to evaluate the air quality is beneficial and feasible; therefore, it is recommended to consider the use of biomonitors in future studies in order to understand the air quality in specific areas since this technique provides acceptable and reliable values.