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.

Concentrations of Co, Ni, Cu, Zn, Pb and Fe in the top-soils (0-10 cm) from urbanized and un-urbanized areas of Havana city were measured by X-ray fluorescence analysis. The mean Co, Ni, Cu, Zn and Pb contents in the urban topsoil samples (13.9 ± 4.1, 66 ± 26, 101 ± 51, 240 ± 132 and 101 ± 161 mg kg(-1), respectively) were compared with mean concentrations for other cities around the world. The results revealed the highest concentrations of metals in topsoil samples from industrial sites. Lowest metal contents were determined in the un-urbanized areas. The comparison with Dutch soil quality guidelines showed a slight contamination with Co, Ni Cu and Zn in all studied sites and with Pb in industrial soils. On the other hand, the metal-to-iron normalisation using Earth crust contents as background showed that soils from urbanized areas in Havana city (industrial sites, parks and school grounds) are moderately enriched with zinc, moderately to severe enriched (city parks and school grounds) and severe enriched (industrial sites) with lead. The values of integrated pollution index (IPI) indicated that industrial soils are middle and high contaminated by heavy metals (1.19 ≤ IPI ≤ 7.54), but enrichment index values (EI) shows that metal concentrations on the studied locations are not above the permissible levels for urban agriculture, except soils from power and metallurgical plants surroundings.

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Epiphytic lichens, collected from 119 sampling sites grown over "Roistonea Royal Palm" trees, were used to assess the spatial distribution pattern of lead (Pb) and identify possible pollution sources in Havana (Cuba). Lead concentrations in lichens and topsoils were determined by flame atomic absorption spectrophotometry and inductively coupled plasma (ICP) atomic emission spectrometry, respectively, while Pb in crude oils and gasoline samples were measured by ICP-time of flight mass spectrometry (ICP-ToF-MS). Lead isotopic ratios measurements for lichens, soils, and crude oils were obtained by ICP-ToF-MS. We found that enrichment factors (EF) reflected a moderate contamination for 71% of the samples (EF > 10). The Pb/Pb ratio values for lichens ranged from 1.17 to 1.20 and were a mixture of natural radiogenic and industrial activities (e.g., crude oils and fire plants). The low concentration of Pb found in gasoline (<7.0 μg L) confirms the official statement that leaded gasoline is no longer used in Cuba.

Concentrations of cobalt, nickel, cooper, zinc and lead in the top-soils (0-10 cm) from a former Havana solid waste open dump were estimated by X-ray fluorescence analysis. The mean metal contents in the dump topsoil samples (in mg kg(-1): 8.4 ± 2.7 for cobalt, 50 ± 27 for nickel, 252 ± 80 for copper, 489 ± 230 for zinc and 276 ± 140 for lead) were compared with mean concentrations from Havana urban soils and from other solid waste disposals around the world. The comparison with Dutch soil quality guidelines showed a serious cooper contamination and a slight contamination with the rest of determined metals. The values of the integrated pollution index (mean index = 3.5) indicated that dump soils are highly contaminated by metals, and the enrichment index values shows that metal concentrations on the studied locations are above the permissible levels for urban agriculture.