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C. D Ezeonyejiaku
C. O Okoye
N. J Ezeonyejiaku
I. I Offorbuike


One of the most significant causes of health problems worldwide is heavy metal contamination of vegetables. Due to their nutritional value and affordability,   regular eating of vegetables is strongly recommended by health experts as being vital for human health. The study evaluated the concentrations of ten (10) selected heavy metals namely, cobalt (Co), copper (Cu), zinc (Zn), cadmium (Cd), lead (Pb), iron (Fe), manganese (Mn), chromium (Cr), nickel (Ni) and mercury (Hg) in some common vegetables such as waterleaf (Talinum triangulare), fluted pumpkin (Telferia occidentalis), and green (Amaranthus viridis) sold at Eke Awka market, Anambra State. This was done to determine the health implications of consumption of heavy metal contaminated vegetables. The vegetables were digested and analyzed using atomic absorption spectrometer (AAS) and was compared to Codex food grade standards and assorted (sub) tropical fruits, edible and inedible peels. The result of the study showed that the concentrations of the heavy metals ranges from 0.103±0.002 μg/g for cobalt, 0.120±0.001 μg/g -1.198±0.001 μg/g for copper, 1.257±0.002 μg/g -1.876±0.005 μg/g -1.974±0.001 μg/g for zinc, 0.027±0.002 μg/g -0.940±1.329 μg/g for cadmium, 0.603±0.002 μg/g -0.607±0.001 μg/g for lead, 2.253±0.001 μg/g -2.664±0.004 μg/g -3.080±0.014 μg/g for iron, 0.975±0.021 μg/g -1.258±0.001 μg/g -3.327±0.001 μg/g for manganese, 0.000±0.000 μg/g for chromium, 0.148±0.001 μg/g -0.299±0.001 μg/g -0.337±0.001 μg/g for nickel, 1.935±0.007 μg/g -2.13±0.014 μg/g -2.727±0.003 μg/g for mercury. The result showed that the concentration of mercury (Hg) and lead (Pb) were high and above the permissible limit of WHO/FAO standard in the sampled vegetables; the study also showed that cadmium (Cd)  was high and above permissible limit of WHO/FAO in Green (Amaranthus viridis) but low in other sampled vegetables. Other analyzed heavy metals such as Co, Cu, Zn, Fe, Mn, Ni have low concentrations and are below the permissible limit of the WHO/FAO. The high concentrations of the heavy metals especially mercury (Hg) and lead (Pb) in the examined vegetables indicate a potential public health threat. Efforts are needed for continuous monitoring of levels of trace elements in vegetables sold to consumers due to variation in contaminating sources to ensure food safety in the locality.


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How to Cite
Ezeonyejiaku, C. D., Okoye, C. O., Ezeonyejiaku, N. J., & Offorbuike, I. I. (2023). RISK OF TRACE METALS IN MARKET VEGETABLES: IMPLICATIONS FOR LEAD AND MERCURY EXCEEDANCES. The Bioscientist Journal, 11(1), 90-105. Retrieved from https://bioscientistjournal.com/index.php/The_Bioscientist/article/view/142
Author Biographies

C. D Ezeonyejiaku



C. O Okoye



N. J Ezeonyejiaku



I. I Offorbuike




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