Mineralogical and chemical characterization of sediments from impervious urban streets

Abstract

This study aimed to determine the granulometric and mineralogical composition and the Cr, Ni and Pb trace element content in sediments collected from impermeable streets located in the urban perimeter of Toledo, PR, Brazil. The mineralogical analyses were performed by a diffractometer, the granulometric analyses by integrated sieving methods and laser diffraction, and the analyses of the trace elements in quartered fractions of the sediments were carried out by optical emission spectrometry with inductively coupled plasma (ICP-OES). It was concluded that the sediments had an average granulometry greater than 0.09 mm, with finer fractions represented by clay. The mineralogy identified ferruginous substances characteristic of Distroferric Red Latosol DRL, with a high presence of quartz and diopside. Statistically, it was shown that the sediment samples were significantly enriched with the trace elements Chromium and Nickel in the central area streets and with Lead in lower concentrations in the streets in the peripheral areas. The sediments have an average particle diameter greater than 0.09 mm, represented by sand, with fine sediments representing 2 to 6% of the samples. The software indicated that the sediments are from different anthropogenic sources. The diffractograms show peaks for quartz and diopside. Enrichment by trace elements was significant for chromium and nickel in the downtown area streets.