Evaluación de contaminantes atmosféricos en los principales mercados de la ciudad de Riobamba.

Abstract

This air quality study aims to identify the concentration levels of atmospheric pollutants in the main markets from Riobamba city. For this purpose, four sites were selected San Pedro de Riobamba Agricultural Producers Market, La Merced, San Alfonso and La Condamine Popular Shopping Center. The concentration was determined by means of the passive sensor technique, which consisted of randomly placing sampling tubes within the markets; the monitored pollutants were NO2, SO2 and O3. The samples collected were analyzed in the Laboratory of Instrumental Chemistry from the Faculty of Sciences, colorimetric tests were carried out to determine the presence of the contaminant in the collectors and the absorbance was measured in a UV-Visible spectrophotometer. It means that to greater absorbance, greater will be the concentration of the pollutant studied; based on current environmental regulations a criterion could be established on the ambient air quality present in the city’s markets. As a result, it was obtained that the points with the highest concentration values are P3 of week 3 from La Merced market to NO2; P2 of week 1 from San Alfonso market to SO2 and P2 of week 3 from EP-Municipal Market of Agricultural Producers to O3 . All the data was adjusted to the real conditions, using temperature and pressure data provided by the ESPOCH weather station, which is the closest to our study area. With these values, it was possible to conclude that in general the prevalence of air pollutants in the markets does not exceed in most of the limits allowed by the law, but they are approached in a significant way, for this reason, it could work in preventive measures to reduce the pollution.