Levels and potential health risk of elements in two indigenous vegetables from Golinga irrigation farms in the Northern Region of Ghana

The study determined the levels of selected metals (Mg, Ca, K, P, B, Na, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, As, Cd, Sb, Ba and Pb) and further performed a health risk assessment on consumption of two traditional African vegetables, jute mallow (Corchorus olitorius) and roselle (Hibiscus sabdariffa) collected from the Golinga irrigation farms in Northern Ghana. The concentration of essential elements ranged between 1.50 (Mo) and 368 (Fe) mg kg(-1 )for Corchorus olitorius and 1.01 (Cu) and 308 (Mn) mg kg(-1) for Hibiscus sabdariffa. Most of the essential elements were within the permissible limits except for Cr (31.9 mg kg(-1) in the wet season) and As (13.4-32.1 mg kg(-1)) which were higher than the WHO/FAO guidelines of 5 and 0.5 mg kg(-1), respectively. The concentration of toxic metals (Cd and Pb) was above the permissible limits in both vegetables reaching 31.4 and 39.0 mg kg(-1), respectively. Human health risk assessment using Hazard Quotients showed that only As had the potential to increase above non-acceptable levels and cause non-cancerous health risks during a life-time consumption of Hibiscus sabdariffa vegetable while Corchorus olitorius is relatively safe and can be a beneficial source of essential elements.