Application of sewage sludge with high lead (Pb) contents may pollute soils and contaminate crops. The objective of this work was to evaluate peanut responses to application of sewage sludge with varying Pb contents in order to supply phosphorus (P) to the plant. A greenhouse experiment was carried out with peanut grown on soil sample from a medium-textured Haplustox. Treatments were arranged in 3 × 2？+？2 factorial scheme, replicated three times, distributed in randomized block design, and consisted of: three Pb rates applied to soil with sewage sludge (3, 21, and 42？mg？kg？1) × two times of sewage sludge application (30 days before peanut sowing and at the day of the sowing)？+？mineral fertilization？+？control (without sewage sludge and mineral fertilization). Sewage sludge was efficient to supply P to peanut. Sewage sludge containing high rates of Pb, when applied, did not harm biomass and yield of the plant, but increased HCl-extractable Pb in soil and Pb content in shoot, roots, and pod husks. Increase of Pb content in pod husks may represent contamination risk of kernels and their products with fragments from husks detached during manipulation or industrial processing of peanuts. 1. Introduction Lead in a naturally occurring trace element in soils with variable total concentrations depending on the parent material and prevalent pedogenetic processes [1], whereas its total content is far higher than the background concentrations in contaminated soils. Elevated Pb concentrations in soil may impact plants and soil microorganisms and cause serious effects in humans such as neurological problems and damages to the central nervous system [2]. Sewage sludge contains Pb and other heavy metals and its application on agricultural soils has been a way sought for disposal of high amounts produced of this waste particularly in large urban areas [3, 4]. While solving the problem of disposal repeated applications of sludge may increase Pb content in soils. Crops grown on these soils can uptake large Pb amounts and transfer it to edible parts [5]. Intake of these parts increases risks to human health. Sewage sludge has been used in agriculture with the purpose of improving soil properties and to supply nutrients to crops [6]. In S？o Paulo state, Brazil, research results show the possibility of using the sludge to supply nutrients to sugarcane without impairing yield and quality of stalks [7] and with low potential for contamination of soil-plant system by heavy metals, including Pb [8]. However, it is essential to know the responses of other crops which might
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