The contribution of heavy metal pollution derived from highway runoff to Guanabara Bay sediments: Rio de Janeiro / Brazil

Abstract

In this study, geochemical and particle size analyses of thirty-four street sediment samples collected from an urban environment around Guanabara Bay, shows highway run-off to be a potential source of heavy metals for the pollution of near-shore sedimentary deposits. Concentrations of Fe, Mn, Zn, Cu, Pb, Cr and Ni were found to be higher in these sediments when compared to concentrations found in samples from the natural environment, where an Enrichment Factor (EF) index was used to distinguish between natural and anthropogenic sources. Particle size analysis shows these sediments to be predominantly composed of sand and no distribution pattern was observed between the sand, silt and clay fractions. High levels of organic matter and heavy metals would indicate that these street run-off materials are a potential source of pollution for the near-shore sediments of Guanabara Bay.

Heavy Metals Contamination of Road-Deposited Sediments

“…In contrary to Pereira et al (2007) observations, some researchers (Ujevic et al, 2000;Zhang et al, 2001;Che et al, 2003;Avila-Perez et al, 1999) found organic matter to be associated with the highest concentrations of heavy metals.…”

“…This low correlation can be indicative of distinctive sources for these metals in these urban areas. Pereira et al (2007) discovered that the particle size distribution for urban street sediments does not obey the laws of the hydrodynamics like materials found in natural environments such as beaches and rivers. For example, in urban environment particulate matter can be deposited in different ways and these include moving parts of vehicles, loads spilling from trucks, accidents, erosion of gardens and atmospheric deposition.…”

“…Cities and Towns under various geographical, geological, climatic and sociological conditions are usually considered as big sources of pollutants irrespective of specific types of men activities (Mielke, 1994;Tiller, 1989). Established research has shown that sediments and dusts transported and stored in the urban environment have the potential to provide considerable loadings of heavy metals to receiving waters and water bodies, particularly with changing environmental conditions (Pereira et al, 2007).…”

“…Urban street sediments have limited residence times and therefore provide a record of recent accumulations (Pereira et al, 2007;Pagotto et al, 2001;Sutherland and Tolosa, 2000;Sutherland, 2003). The aim of this study was to examine the extent of heavy metal contaminations in Bida road-deposited sediments.…”

Un método para evaluar el enriquecimiento de metales en sedimentos marinos en Costa Rica

“…N: number of samples, b: intercept, m: slope, t Student, and Fisher's F. Pereira et al 2007, Graham & Semmes 2005, Kress et al 1998, García-Céspedes et al 2004, con los cuales se pueden evaluar las concentraciones medidas en este estudio. Utilizando la información del Cuadro 1 y del Cuadro 7, se nota que las concentraciones de aluminio y manganeso encontradas en Bahía Culebra están en el ámbito en que se encuentran en las rocas o en las arcillas de sedimentos marinos.…”