The objective of this experiment was to evaluated the heavy metal, K and Na in the substrate after the harvest of lettuce, in a experiment with cultivars Brasil 48, Regina 71, Vitória Verde Clara e Grand Rapids and doses of organic compost of municipal waste 0, 17.5, 35 e 52.5 t ha-1, in greenhouse. The variables analised were pH in water, electric conductivit, organic carbon, and avaiable contents of Pb, Cu, Mn, Zn, K and Na in the soil. Results demonstrated that doses of organic compost disturbed the values of pH, organic carbon, electric conductivit, and the avaiable contents of Pb, Cu, Mn, Zn, K and Na in the substrate after the harvest of the four cultivars. Lettuce cultivars influenced the values of organic carbon and the contents of Cu, Mn, Zn K and Na of the same substrate. Increasing the dose of organic compost, values of Pb, Cu, Mn, Zn, K, Na, pH, electric condutivit and organic carbon were increased.
heavy metals; organic compost; urban waste; lettuce