ANALYSIS OF LEAD ADSORPTION IN OXISOLS AND EVALUATION OF ITS PHYTOAVAILABILITY P. R. FRADE 1 , L. R. de OLIVEIRA 2 , C. C. de AMORIM 1 , M. M. D. LEÃO 1 e E. O. NETO 3 1 Universidade Federal de Minas Gerais, Departamento de Engenharia Sanitária e Ambiental 2 Centro Universitário de Formiga , Departamento de Engenharia Ambiental 3 Universidade Federal de Minas Gerais, Departamento de Engenharia Metalúrgica e de Materiais E-mail para contato: paulorfrad@gmail.com ABSTRACT – Adsorption reactions in the mobility and availability of lead (Pb) in soils and uptake by plants are important because of its potential for contamination of humans and animals. Considering the lack of information of this nature in variable charge soils, this paper aimed to study the chemical and physical properties of soils collected in five points the margin of a highway, analyze the reactions of these five soils and tomatoes (Lycopersicon esculentum) at different pH values and four concentrations of lead, applied in the form of nitrate, and to correlate the properties of the soil and the results obtained. We analyzed different chemical and physical properties of soils and the levels of lead, before and after 60 days to start the experiment. The soils under study were classified as medium texture and clayey and lead values found are within the range of natural levels in the soil. The interaction effects were only observed between the treatments containing higher doses of lead nitrate added and pH adjusted to 6.5. Samples of tomatoes were separated into aerial part and fruits and then analyzed for lead content. In tomato aerial part, the significant difference was only observed with the higher dose, whereas in the fruit Pb concentrations were below the detection limit. 1. INTRODUCTION Lead (Pb) is a heavy metal potentially toxic to humans and animals. Therefore, its use tends to be restricted in order to minimize the risks from their accumulation in soils, water and air. The increasing use of land transport powered by fossil fuels has caused a significant increase in environmental pollution on land areas adjacent to roads. During the road’s cycle life are produced by the materials used to build it and the movement of vehicles, compounds that may contaminate the environment (ANDREOLI, 1998). The final fate of heavy metals is its accommodation and infiltration in soils and sediments. Heavy metals are often accumulate in the top soil layer and are then accessible to the roots of plants. The soil has a great capacity to retain heavy metals, however, if this capacity is exceeded, the metal availability in the middle penetrate the food chain of living organisms or are leached, jeopardizing the quality of the groundwater system (PAOLIELLO; CHASIN, 2001). Área temática: Engenharia Ambiental e Tecnologias Limpas 1