Environmental PM2.5 levels and distance from a heavy traffic road in Ciudad Juarez, Chihuahua, Mexico

Objective. To assess PM2.5 levels at different distances from a heavy traffic road. Material and Methods. Daily measurements of PM2.5 were taken between August 26 and 30, 2002, at different distances from Tecnologico Avenue in Ciudad Juarez, Chihuahua, Mexico. Data analysis consisted of descriptive statistics for each distance and Kruskal Wallis and cross trend for ranks. Results. We found a significantly decreasing trend of PM2.5 median levels with increasing distance from Tecnologico Avenue (p < 0.001). At 100 m distance from the avenue PM2.5 levels decreased by 9.5 mug/m3 (40.6%) when compared to median levels registered on the avenue. The results showed a highly significant negative correlation between PM2.5 measurements and the distance from the avenue (r=-0.70, n=20 and p=0.0005). Conclusions. PM2.5 median levels decreased significantly after 100 meters from heavy traffic roads. These results are of great relevance when assessing exposure to PM2.5 in epidemiological studies.The English version of this paper is available at:http:/ /www.insp.mx/salud/46/eng.