RISK OF HEAVY METAL INTAKE VIA CONSUMPTION OF SPINACH AND ROSELLE IRRIGATED WITH URBAN WASTEWATER IN YOLA AND KANO, NIGERIA
The level of Cadmium (Cd), Lead (Pb), Copper (Cu) and Chromium (Cr) in Spinach (Amaranthus candatus L) and Roselle (Hibiscus subtaritta L) irrigated with urban wastewater in Fagge - Kano and Shinko - Yola were investigated. The heavy metal concentrations in the wastewater used for irrigation at both sites were analyzed including the daily intake of heavy metal through consumption of the two vegetables. Atomic Absorption Spectrophotometer was used for the analysis of both water and plant samples. The concentrations of Cd, Pb, Cu and Cr in almost all the vegetables exceeded the maximum permissible limit of 1.5 mg kg-1, 2.5 mg kg-1, 73 mg kg-1 and 30 mg kg-1 respectively as set by the World Health Organization and Food Agricultural Organization (WHO/FAO). The estimated daily intake rate of Cd, Pb and Cu as a result of consumption of Spinach and Roselle leaves ranged from 23.10 – 37.65 mg/day, 4.13 – 24.75 mg/day and 6.60 – 14.03 mg/day which were far above the maximum tolerable daily intake limits of 0.06 mg/day, 0.21 mg/day and 1.2 mg/day respectively. This alarming intake rate of the heavy metals in the study areas could lead to bioaccumulation and toxicity resulting in serious health risks such as kidney damage, bronchitis, bone marrow cancer and mental retardation.
Authors : T. M. Chiroma, A. O. Becky and Y. Luka
Category : Open Access Volume (Issue) : 3(1) Date Uploaded : 25th March 2018