EXTRAÇÃO DE METAIS TÓXICOS EM SOLOS CONTAMINADOS UTILIZANDO O MILHO COMO POSSÍVEL FITORREMEDIADOR

Abstract

The phytoremediation is an alternative in the decontamination of the environment, in which plants capable of absorbing contaminating ions are used. Thereby, the scientific research aims to verify if the corn can phytoextract, accumulate, hyperaccumulate and tolerate toxic metals in the plant biomass in anthropically contaminated soils. The experimental design was completely randomized, consisting of four treatments with four replications, totaling sixteen portions for each contaminant. The application of metals and EDTA were carried out in the form of a solution, contaminating the soil 46 days after maize maturation in pots. The concentrations were above the intervention values of CETESB. Soil and plant tissues analyzes were performed by the Atomic Absorption Spectrometer, which resulted in significant concentrations. The results of the Analysis of Variance and post-hoc Tukey's Test, suffered a reduction in dry biomass and an increase in the accumulated amount. Corn was tolerant to the highest dose of lead, but it was intolerant to the highest doses of cadmium and chromium. Thus, the results indicated that the maize phytoextracted contaminants efficiently, but it cannot be used as a phytoremediator in contaminated sites because they cause food poisoning for the living beings, once corn is used in Brazil and worldwide for animal feed and for the food industry of high nutritional and energy qualities.