Resumo

CARRASQUERO-DURAN, Armando. Determination of lead contamination levels in soils and dust of streets of Maracay. Agronomía Trop. [online]. 2006, vol.56, n.2, pp.237-252. ISSN 0002-192X.

In this work the levels of lead in soils and street dusts taken from the urban area of Maracay city were quantified by flame atomic absorption spectrometry after and acid digestion with aqua regia. A total of 243 surface soil samples and 36 street dust samples of the most important avenues were taken. Lead level were in the range of 33 to 11,113 µg g^-1 with a prevalence of values between 2,000 and 4,000 µg g^-1 which are significantly higher than the accepted levels for uncontaminated soils in several international regulations. The most polluted sites were located in the Sucre, Casanova, Fuerzas Aereas and Constitucion avenues, which was attributed to the intense traffic of vehicles which used lead treated gasoline. Street dusts also showed high levels of lead pollution increasing the risks of lead exposition, because the finest polluted particles could be transported by the wind dispersing the contaminant. Vertical distribution of lead in soils reflected a high metal accumulation in the surface being consistent with a process of anthropic pollution. In general, soils of Maracay City are strongly impacted by lead pollution whose origin may be associated with the combustion of gasoline treated with lead tetraethyl.

Palavras-chave : Lead; pollution; soils; acid digestion; street dust; Maracay.