Assessment of sugarcane grown in wetlands polluted with wastewater

Abstract Wastewater effluents directly discharged into nearby stream are eventually used to irrigate plants like sugarcane in Ghana. In this study, 24 triplicates sugarcane stems (sugarcane juice was extracted), 24 triplicates soil samples and 8 triplicates water samples were collected from sugarcane farms in four communities in Ashanti region of Ghana. Two of the communities were exposed to wastewater while the other two without wastewater contamination served as control. Metals (Pb, Cd, Cr, Cu, and Fe) concentration were determined in the digested samples using Spectra AA 220 flame atomic absorption spectrometer. The Pb concentration in all sugarcane juice samples ranged between 12.65 and 145.0 μg/L. The mean Cu concentration of the sugarcane juice samples varied between 11.28 and 156.00 μg/L. In general, there were decrease in metals investigated in sugarcane juice as you move away from the stream. However, the reduction was more pronounced in the hotspot sampling areas than control sampling areas. The EDI value was 9.76 × 10−4, 2.94 × 10−5, 1.09 × 10−3, and 9.07 × 10−3 (mg/kg-day) for Pb, Cd, Cu, and Fe, respectively. Mean hazard quotient (HQ) for the metals studied ranged from 0.036 (Fe) to 0.286 (Pb). The results of this study indicate that sugarcane is able to grow in soils where some metals are accumulated. High levels of metals were pronounced in sugarcane originating from wastewater polluted soils as those considered in this study. The consumption of normal quantity of sugarcane juice may not present detrimental health concerns through a lifetime based on the metals contents alone.