Resumo

MACHADO, Analí et al. Metal contamination of air, street dust and soil in a high traffic area. Rev. Int. Contam. Ambient [online]. 2008, vol.24, n.4, pp.171-182. ISSN 0188-4999.

Due to the important health effects of inhalable particles (PM₁₀) and its associated metals, levels of four trace metals (Pb, Ni, Zn, Cr) generated by mobile sources with variable toxicity incorporated to PM₁₀ atmospheric samples in a high density traffic area were evaluated. Samples were collected at two different sites (being considered as emission and dispersion areas) during a dry-wet season period, using a low volume air sampler equipped with quartz fiber filters; after an acid extraction, samples were analyzed by atomic absorption spectrometry. PM₁₀ concentrations were two times higher in the emission area than in the dispersion area for both climatic regimens, but exhibited a better correlation between sites during the dry season. All the elements showed statistically significant differences between monitoring sites. On the other hand, when the total sampling period for PM₁₀ is compared for all the tested metals, significant differences between sites and between meteorological seasons can be appreciated. The Venezuelan air quality standard for Pb was not exceeded, but a mean concentration of 1.13 µg/m³ -very close to Venezuelan and USEPA standard-was obtained at the emission site. Nevertheless, Pb and Ni reported levels for both locations were above the OMS allowed limit during the whole sampling period. Further, the statistical analysis demonstrated the selection of the monitoring areas was adequate, confirming that motor vehicles are the main emission source of these atmospheric pollutants.

Palavras-chave : vehicular emissions; PM₁₀; metals; street dust; soil.