Intra-urban variability of long-term exposure to PM2.5 and NO2 in five cities in Colombia

Abstract

Rapidly urbanizing cities in Latin America experience high levels of air pollution which are known risk factors for population health. However, the estimates of long-term exposure to air pollution are scarce in the region. We developed intraurban land use regression (LUR) models to map long-term exposure to fine particulate matter (PM2.5) and nitrogen dioxide (NO2) in the five largest cities in Colombia. We conducted air pollution measurement campaigns using gravimetric PM2.5 and passive NO2 sensors for two weeks during both the dry and rainy seasons in 2021 in the cities of Barranquilla, Bucaramanga, Bogotá, Cali, and Medellín, and combined these data with geospatial and meteorological variables. Annual models were developed using multivariable spatial regression models. The city annual PM2.5 mean concentrations measured ranged between 12.32 𝛍g/m3 and 15.99 𝛍g/m3 while NO2 concentrations ranged between 24.92 𝛍/m3) and 49.15 𝛍g/m3. The PM2.5 annual models explained 82% of the variance (R2) in Medellín, 77% in Bucaramanga, 73% in Barranquilla, 70% in Cali, and 44% in Bogotá. The NO2 models explained 65% of the variance in Bucaramanga, 57% in Medellín, 44% in Cali, 40% in Bogotá, and 30% in Barranquilla. Most of the predictor variables included in the models were a combination of specific land use characteristics and roadway variables. Cross-validation suggest that PM2.5 outperformed NO2 models. The developed models can be used as exposure estimate in epidemiological studies, as input in hybrid models to improve personal exposure assessment, and for policy evaluation.

Winter and Summer PM2.5 Land Use Regression Models for the City of Novi Sad, Serbia

“…Monitoring air pollutants for LUR development is often time-limited to several sampling campaigns during the year, lasting one or two weeks [33][34][35]. Seasonal PM2.5 LUR models have been developed in Asia [36], Canada [37], Iran [38] and Colombia [34].…”

“…Monitoring air pollutants for LUR development is often time-limited to several sampling campaigns during the year, lasting one or two weeks [33][34][35]. Seasonal PM2.5 LUR models have been developed in Asia [36], Canada [37], Iran [38] and Colombia [34]. Previously, in Serbia, adaptations of the European LUR model developed by Wang et al in 2014 within the ESCAPE study [24] and its validation with the development of supporting average daily traffic intensity models, and data fusion simulation were performed in Belgrade for PM2.5 by Davidović et al [39] and for NO2 by Davidović et al [40].…”