Estudio de exposición personal a nano partículas considerando variables meteorológicas en cuatro corredores viales de la localidad de Chapinero, Bogotá

Abstract

This study present concentrations of nano-particles at the breathing zone in 4 different types of parallel roads of the same area in the city, Bogota Col: The Carrera 7, Carrera 13, Avenida Caracas and Carrera 15; considering influence of meteorological variables such as wind speed and direction, temperature and relative humidity; as well as variables related to technology and number of emission sources circulating in each of the streets. Nano-particle concentration measurements were developed using a Diffusion Size Classifier DiSCmini, also was used a portable weather station Davis located to 2.5 m height. The measurement campaign was carried out from December 15 of 2015 to February 19 of 2016, during working days in rush hour because of recordings of PM 2.5 and Black Carbon according to the Air Quality Monitoring Network. Two methodologies were evaluated; one considering a single measurement point on one sidewalk of the street and the second methodology considering the two sidewalks of the street and the central pavement when exist, each street was characterized spatially and vehicle counts picked out for types. The results show statistic differences between methodologies, also differences in the concentrations of each of the streets, high incidence of variation of the data in those with high number of vehicles. In example, over Carrera 15 the amount of vehicles circulating per hour is less than 20 and not presented exceedances for concentrations higher than 1’000.000 #/cm3, in contrast other corridors where exceedances are close to 15% of total data recorded. The comparison between nano-particles concentration and the meteorological variables show low correlations using the Pearson correlation.