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Although sewage sludge provides nutrients for plant growth, its continual use over extended periods can result in the accumulation of heavy metals to levels detrimental to the environment. A study was conducted to determine the concentration of EDTA-extractable Zn, Cu, Ni and Pb in a Gleyic Lixisol that had been amended with sewage sludge for more than 19 years in Zimbabwe. Soil profiles were dug and samples taken for metal analysis using inductively-coupled plasma atomic emission spectrophotometry (ICP-AES). Sewage sludge addition resulted in a significant (P<0.01) increase in the concentration of the four metals in the top soil (0–15cm), and there was a significant (P<0.01) treatment×soil depth interaction. Zinc decreased from 196mgkg⁻¹ in the top soil (0–5cm) to 5mgkg⁻¹ in the 15–20cm horizon while Cu, Ni and Pb decreased from 43 to 11, 23 to 9 and 53 to 19mgkg⁻¹, respectively. It was concluded …