Heavy Metal Contents in Cuban Soils.

Heavy Metal contents in Cuban soils. Olegario Muniz1, Mirelys Rodriguez2 and Alfredo Montero2 1University of Florida, IFAS, Gainesville, FL. Email: omunizugarte@ufl.edu 2Soil Institute, Ministry of Agriculture, La Habana, Cuba. ABSTRACT The evaluation of the maximum permissible Heavy Metal (HM) contents in the soil is a way to prevent the entry of a non-suitable amount of them into the food chain, due to their potential toxicity for human health. The objective of present study was to obtain a Cuban first approach about criterion in order to evaluate the presence of HM in soils in non-permissible quantities. It was employed the Brazilian methodology CONAMA, the analytical technique 3051A, ICP, AAS, and samples of 35 types of soils representative of the country, with minimal anthropic action. Risk analysis for Cuban conditions was also considered. It was established, for the Cuban soils, three values ??for the metals Cadmium (Cd), Lead (Pb), Mercury (Hg), Arsenic (As), Zinc (Zn), Copper (Cu), Nickel (Ni), Chromium (Cr), Cobalt (Co), Vanadium (V), Antimony (Sb) and Molybdenum (Mo). Values ??denominated: Value ??of Reference (VR), that are the natural contents of the HM due to the parental material without influence of the human activity; Value of Study ??(VS), value ??above which there is a risk to human health and the development of living organisms; and Value for Alert ??(VA), an intermediate value between the two previous ones. Results showed that the natural values ??of many of the studied HM in the soil (VR) were higher than the world average. Sequential extraction of the metals in some types of soil with the highest total content, such as Ni and Cr, showed that they are in forms not readily available to the plants. It was finally analized the origin and forms in which Ni and Cr are found in Cuban soils due to their specificities. Key words: Heavy metals, soil pollution, soil quality