Urban dust from mexico city roads: A spatially linear analysis of potentially toxic elements, magnetic properties and particle size

Urban dust is a reservoir of potentially toxic elements and particles of various sizes that represent a risk to human health, hence the importance of determining its characteristics. The objectives of this study were the identification of the sites of greatest contamination by potentially toxic elements, magnetic material and particle size in urban dust, as well as evaluating the influence that different types of public transport have on urban dust. Six primary roads were selected, based on constant vehicular traffic during the day, an average travel speed of 30 km/h, and circulation of a single type of public transport. The urban dust sample was taken in an area of 1 m(2) on the asphalt strip. Potentially toxic elements, magnetic properties and particle size were analyzed. The urban dust of the roads of Mexico City had variable concentrations of Cr, Cu, Pb, V, Zn, PM10, PM2.5 and magnetic material. The elements with highest concentration in urban dust were Zn and Pb. The content of PM10 and PM2.5 in urban dust was 10 to 30 % of the total weight of the sample. The areas with the greatest accumulation are located at road crossings, roads near the airport and the industrial park.