Heavy Metal Accumulation and Phytoremediation Potential of Talinum triangulare in Metal Scrap Contaminated Soils in Owerri, Nigeria

Chinonso Ebeh; Roselyn F. Njoku-Tony; Christopher C. Ejiogu; Tochi E. Ebe; Chukwukere Orike

doi:10.56201/ijgem.vol.12.no3.2026.pg177.188

📄 Download Paper

Heavy Metal Accumulation and Phytoremediation Potential of Talinum triangulare in Metal Scrap Contaminated Soils in Owerri, Nigeria

Chinonso Ebeh, Roselyn F. Njoku-Tony, Christopher C. Ejiogu, Tochi E. Ebe, Chukwukere Orike

Abstract

Metal scrap recycling activities in urban and peri-urban areas of developing countries generate soil contamination that threatens food safety and human health. This study evaluated the phytoremediation potential of Talinum triangulare (waterleaf), a widely consumed leafy vegetable in West Africa, growing on soil contaminated by metal scrap operations in Owerri, Nigeria. Soil and plant samples were collected from three metal scrap sites and a control location. Concentrations of lead (Pb), cadmium (Cd), chromium (Cr), nickel (Ni), and zinc (Zn) were determined in soil, roots, and shoots using atomic absorption spectrophotometry after acid digestion. Phytoremediation potential was assessed through bioconcentration factor , translocation factor (TF), and bioaccumulation coefficient . Results revealed severe soil contamination at metal scrap sites, with mean concentrations of Pb (485 ± 102 mg/kg), Cd (12.8 ± 3.2 mg/kg), Cr (268 ± 58 mg/kg), Ni (156 ± 34 mg/kg), and Zn (542 ± 98 mg/kg) substantially exceeding regulatory limits and control values. T. triangulare accumulated considerable metal concentrations in roots (Pb: 142 mg/kg, Cd: 8.5 mg/kg, Cr: 95 mg/kg, Ni: 68 mg/kg, Zn: 285 mg/kg) and shoots (Pb: 38 mg/kg, Cd: 4.2 mg/kg, Cr: 28 mg/kg, Ni: 22 mg/kg, Zn: 158 mg/kg). Bioconcentration factors ranged from 0.26-0.53, indicating moderate metal uptake from soil. Translocation factors were generally low (<0.5 for Pb, Cd, Cr) to moderate (0.55 for Zn), suggesting preferential root accumulation characteristic of phytostabilization rather than phytoextraction. Metal concentrations in edible shoots exceeded WHO/FAO permissible limits for leafy vegetables, posing significant food safety concerns. The study demonstrates that while T. triangulare shows limited phyto-extraction capacity unsuitable for large-scale soil decontamination, it exhibits phytostabilization potential that could contribute to ecological risk reduction. However, consumption of waterleaf from metal-contaminated sites presents serious health risks, necessitating public awareness campaigns and cultivation site monitoring. These findings contribute to understanding metal accumulation patterns in tropical leafy vegetables and inform phytoremediation strategies for metal-contaminated urban soils in West Africa.

Keywords

Heavy metals; Phytoremediation; Talinum triangulare; Metal scrap; Bioconcentration; Translocation; Food safety IIARD International Journal of Geography & Environmental Management

References

Ali, H., Khan, E., Sajad, M.A., 2013. Phytoremediation of heavy metals—Concepts and applications. Chemosphere 91(7), 869-881. Ali, H., Khan, E., Ilahi, I., 2019. Environmental chemistry and ecotoxicology of hazardous heavy metals: Environmental persistence, toxicity, and bioaccumulation. J. Chem. 2019, 6730305. Genchi, G., Sinicropi, M.S., Lauria, G., Carocci, A., Catalano, A., 2020. The effects of cadmium toxicity. Int. J. Environ. Res. Public Health 17(11), 3782. Iweala, E.E.J., Okunlola, A.I., Olawuyi, O.J., 2015. Proximate composition and phytochemical screening of waterleaf (Talinum triangulare Jacq. Willd.) and pumpkin (Telfairia occidentalis Hook. F.) leaves. IJBAS-IJENS 15(2), 129-132. Kumar, V., Pandita, S., Singh Sidhu, G.P., Sharma, A., Khanna, K., Kaur, P., Bali, A.S., Setia, R., 2020. Copper bioavailability, uptake, toxicity and tolerance in plants: A comprehensive review. Chemosphere 262, 127810. Muthusaravanan, S., Sivarajasekar, N., Vivek, J.S., Paramasivan, T., Naushad, M., Prakashmaran, J., Gayathri, V., Al-Duaij, O.K., 2018. Phytoremediation of heavy metals: Mechanisms, methods and enhancements. Environ. Chem. Lett. 16(4), 1339-1359. Njoku-Tony, R.F., Onyeike, E.N., Ogbuji, S.C., 2020. Heavy metal concentrations in soils around metal scrap dumpsites in Port Harcourt, Nigeria. Int. J. Environ. Pollut. Res. 8(2), 15-28. Obiri, S., Dodoo, D.K., Okai-Sam, F., Essumang, D.K., 2016. Cancer and non-cancer risk assessment from exposure to arsenic, cadmium and copper by resident adults and children in the Obuasi municipality, Ghana. Environ. Geochem. Health 38(2), 597-611. Ogundiran, M.B., Osibanjo, O., 2008. Heavy metal concentrations in soils and accumulation in plants growing in a deserted slag dumpsite in Nigeria. Afr. J. Biotechnol. 7(17), 3053- 3060. Opaluwa, O.D., Aremu, M.O., Ogbo, L.O., Abiola, K.A., Odiba, I.E., Abubakar, M.M., Nweze, N.O., 2012. Heavy metal concentrations in soils, plant leaves and crops grown around dump sites in Lafia Metropolis, Nasarawa State, Nigeria. Adv. Appl. Sci. Res. 3(2), 780- 784. Peng, K., Luo, C., Lou, L., Li, X., Shen, Z., 2009. Bioaccumulation of heavy metals by the aquatic plants Potamogeton pectinatus L. and Potamogeton malaianus Miq. and their potential use for contamination indicators and in wastewater treatment. Sci. Total Environ. 407(21), 5317-5324. Tchounwou, P.B., Yedjou, C.G., Patlolla, A.K., Sutton, D.J., 2012. Heavy metal toxicity and the environment. In: Luch, A. (Ed.), Molecular, Clinical and Environmental Toxicology, Vol. 101. Springer, Basel, Switzerland, pp. 133-164. Yoon, J., Cao, X., Zhou, Q., Ma, L.Q., 2006. Accumulation of Pb, Cu, and Zn in native plants growing on a contaminated Florida site. Sci. Total Environ. 368(2-3), 456-464.

Heavy Metal Accumulation and Phytoremediation Potential of Talinum triangulare in Metal Scrap Contaminated Soils in Owerri, Nigeria

Abstract

Keywords

References

More Articles from IIARD INTERNATIONAL JOURNAL OF GEOGRAPHY AND ENVIRONMENTAL MANAGEMENT