Spatial Distribution and Contamination Assessment of Heavy Metals in Urban Topsoils from Las Tunas City, Cuba

Abstract

Concentrations of Cr, Co, Ni, Cu, Zn, Pb and Fe in the topsoils (0-10 cm) from Las Tunas city were measured by X-ray fluorescence analysis. The mean Cr, Co, Ni, Cu, Zn and Pb contents in the urban topsoil samples (97 ± 30, 14 ± 2, 35 ± 36, 94 ± 26, 199 ± 87 and 42 ± 29 mg kg⁻¹ dry weight, respectively) were compared with mean concentrations for other cities around the world with similar population. Cr content in school grounds, parks and residential areas exceed in 20 % the average Cr background level. Highest content for Ni was determined in residential areas, for Zn in market gardens soils and as for Pb, the highest topsoil-background content ratios were observed for market gardens (2.7) and residential areas (2.3). Spatial distribution maps indicated the same behaviour for Cr-Co-Ni and Pb-Zn, respectively, whereas the spatial distribution of Cu differs from other heavy metals. On the other hand, the metal-to-iron normalisation, using (10-20 cm) bottom soil contents as background, showed that topsoils in Las Tunas city are severely enriched with lead and not enriched with the rest of the determined metals. The average values of integrated pollution index (IPI) indicated that soils are moderately contaminated by heavy metals (1.17 ≤ IPI(ave) ≤ 1.39), but enrichment index values shows that metal concentrations on the studied locations are not above the permissible levels for urban agriculture.

Potentially Toxic Elements in Urban Soils of Havana, Cuba

“…Anthropogenic activities (fuel combustion, smelting industry, and soil organic amendments) may contribute to increasing the concentrations of these elements in some samples. Accordingly, Díaz-Rizo et al [38] report high bivariate correlations among Co, Cr, and Ni in soils of Las Tunas City (NE Cuba), which they interpret as a result of a common natural (nonanthropogenic) origin.…”

“…However, by comparing soils from urban and nonurbanized areas, these authors conclude that Pb and Zn have a human origin, while Cu, the same as Co and Ni, may have a lithogenic character. Furthermore, for Las Tunas soils, Díaz-Rizo et al [38] report a high correlation between Pb and Zn, which are considered anthropogenic elements. Because Cu is an abundant element in ultramafic rocks, its presence in Havana soils may have in part a geological origin, but the PCA points to an important anthropogenic contribution.…”

On the Development of Nuclear Physics in Cuba

“…101,102,103,104,105,106 Methods of quantification 107,108 were also developed in different tests in the fields of nuclear medicine, radiological studies, and the modeling and simulation of experimental facilities. 109,110,111,112,113,114,115 In addition, the level of heavy metal pollution in marine sediments and in urban soils of important cities in the country 116,117,118 have also been studied.…”

Contaminación Por Metales Pesados De La Microcuenca Agropecuaria Del Río Huancaray– Perú

“…Sobre el análisis por FRX, este consiste en la determinación de elementos pesados en muestras sólidas 8 ; con esta técnica se identificaron elementos como K, Ca, Mn, Fe, Cu, Zn y Cr en muestras de tabaco de cigarrillos; también se detectó en la polvareda de la ciudad de Camagüey 9 . Otro estudio que aplica este análisis menciona que los lagos y humedales de Caohai (China) están contaminados por metales pesados de origen natural como antropogénico 10 , y la presencia de Hg, Cd y Zn está en niveles de riesgo moderado a nivel de riesgo alto.…”

“…9 10,9 1,6 0,7 0,1 0,1 0,3 1158,0 554,4 628,8 538,0 111,4 176,7 62,3 90,6 38,1 15,2 47,6 45,4 50,5 DE 1,3 3,1 0,3 0,1 0,0 0,0 0,0 300,2 104,9 100,9 163,5 21,1 41,6 6,8 18,8 5,7 4,1 16,6 5,9 17,8 Med 5,8 6,1 11,8 0,6 0,1 0,1 0,2 728,4 477,9 524,0 300,0 92,2 111,2 52,1 64,4 30,0 9,7 18,5 41,2 37,9…”