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This study focuses on the concentration levels of heavy metals copper, zinc, lead, iron and cobalt in Amaranthus species grown in a local garden located at Chang’ombe-Mchicha area in Temeke District in Dar es Salaam region, Tanzania. The garden is irrigated by wastewater from a stream flowing nearby and which passes through the industrial areas before reaching the garden. The heavy metal levels in the vegetable were determined using Atomic Absorption Spectrophotometer (AAS). The findings revealed leaves to have higher heavy metal concentrations than stems and roots. The average concentration for copper ranged from 1.14 to 1.70 mg/100 g dry weight, zinc 6.87 to 11.59 mg/100 g, iron 13.40 to 33.65 mg/100 g, lead 0.49 to 2.27 mg/100 g and cobalt 0.14 to 0.27 mg/100 g. These values were higher than the provisional maximum tolerable daily intake standards recommended by FAO/WHO codex committee on contaminants in foods. The high observed values put consumers of the vegetable grown in the study area at health risk over time unless urgent and right steps are to be taken by the responsible authority to address this issue. Thus, the findings are important to consumers and policy makers.