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The concentration of NORMs and some toxic heavy metals in some nuts and seeds commonly consumed in the south-western states of Nigeria were investigated. The analysis was done with NaI(TI) spectrometry and Inductively Coupled Plasma (ICP) respectively. The concentration of 226Ra, 232Th, and 40K in the samples was found to be below the world average. The mean values are 6.6±1.8, 3.6±1.0 and 98.2±13.5 Bq/kg, in nuts and 8.4±2.6, 2.6±1.3 and 97.6±15.0 Bq/kg in seeds respectively. The effective dose in nuts was calculated to be 13.99 and 12.0 µSv in seeds. The fatal and hereditary cancer risk estimated from the consumption of the nuts and seeds are lower than 1.0 x 10-6 which is the lowest limit. Concentration of metals in the samples descend as Fe > Zn > Cu > Cr. The Hazard Indices of heavy metals are lower than 1 except for in Cocoa which is higher than 1 due to the high concentration of Cu and Fe. Therefore, the nuts and seeds analyzed in this study are contaminated with Cu and Fe and so must be taken with care so that consumers will not be exposed to excessive concentration of these metals which may have undesirable effects.
International food safety authorities network. Information on nuclear accidents and radioactive contamination of foods international food safety authorities network. World Health Organization (WHO), Geneva. INFOSAN; 2011.
Jarup L. Hazards of heavy metals contamination, Bri. Med. Bull. 2003;68(1): 167-82.
Mahurpawar M. Effects of heavy metals on human health, Int. J. Res. Granthaalayah. 2015;1-7.
Lanre-Iyanda TY, Adekunle IM, Assessment of heavy metals and their estimated daily intakes from two commonly consumed foods (Kulikuli and Robo) found in Nigeria. Africa J. Food. Agri. Nutr. Devt. 2012;12(3):6156-6169.
Ademola AK, Omoboyede JO Health risk assessment of natural radionuclide and heavy metals in commonly consumed medicinal plants in South-West Nigeria. Ife J. Sci. 2018;20(3):529-537.
Yin LL, Tian Q, Shaq XZ, Kong XY, Qiu JY. Determination of trace elements in edible nuts in the beijing market by ICP-MS. Biomed. Envir Sci. 2015;28(6):449- 454.
Chung KH, Shin KO, Hwang HJ, Choi KS, Chemical composition of nuts and seeds sold in Korea. Nat. Res Prac. 2013;7(2), 82– 88.
El-Zakla T, Abdel-Ghny HA, Hassan AM. Natural radioactivity of some local fertilisers. Romanian J. Phys. 2007;52: 731–739
Johnson R. Food fraud and economic motivated adulteration of food and food ingredients, Congressional Research Service of US Department of Agriculture. Congressional Research Service. 2014;7-5700.
European Food Safety Authority. Cadmium. Scientific opinion of the panel on contaminants in the food chain of the European Food chain (CONTAM Panel). EFSA. 2009;J.980:1-139.
Atomic Energy Regulatory Board. Accreditation of laboratory for measurement of radionuclide content in commodities. Atomic Energy Regulatory Board, Mumbai; 2003.
Sathyapriva RS, Rao DD, Prabhath RK. Choosing an appropriate method for measurement of 232Th in environmental samples. Radiat. Prot. Enviro. 2017;40: 90 94. DOI:https://doi.org/10.4103/rpe.RPE_20_17
Harb SRM. Natural radioactivity concentrations in some medicinal plants and annual committed effective dose from their consumption. Radiat. Prot. Enviro. 2015;38(1&2):35-38. Available:https://doi.org/10.4103/0972-0464.162816
World Health Organisation (WHO) Data published for Life Expectancy in Nigeria; 2018.
Available:www.who.int › countries › nga
International Commission on Radiological Protection. 1990 Recommendation of the International Commission on radiological protection. Oxford: Pergamon Press. ICRP publication 60, Annals of the ICRP. 1991; 21(1-3).
Taskin H, Karavus M, Ayb B, Topuzoglu A, Hidiroglu S, Karahan G. Radionuclide concentrations in soil and lifetime cancer risk due to gamma radioactivity in Kirklareli, Turkey. J. Environ. Radioactiv. 2009;100.49–53. Available:https://doi.org/10.1016/j.jenvrad.2008.10.012
United State Environmental Protection Authority, Diffuse NORM waste characterization and preliminary risk assessment. S. Cohen and Associates, Inc. Rogers & Associate Engineering Corp. US Environmental Protection Agency. Office of Radiation and Indoor Air (ANR-459);1993.
United States Environmental Protection Agency. EPA regional screening level (RSL) summary table. Washington, DC; 2011.
World Health Organization. Guidelines on assessing quality of herbal medicines with reference to contaminants and residues. Geneva, World Health Organization; 2007.
Food and Agriculture Organization/World Health Organization (FAO/WHO). Joint Expert Committee on Food Additives. Summary and conclusions. 53rd Meeting, Rome; 1999.
Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological profile for Cu. U.S. Department of Health and Human Services. Public Health Service; 2004.
Available:www.atsdr.cdc.gov › toxprofiles
Muhammad A, Sreebas CB. Assessment of heavy metals concentration in some selected medicinal plants collected from BCSIR, Chittagong Cultivation Area in Bangladesh, Hamdard Medicus. 2012; 55(3):26-32.
Ashish B, Necti K, Himanshu K. Copper toxicity: A comprehensive study. Research J. Recent Sci. 2013;2:58–67.
Adefila EO, Onwordi CT, Ogunwande IA. Level of heavy metals uptake on vegetables planted on poultry droppings dumpsite, Arch. Appl. Sci. Res. 2010;2(1): 347-353.
Gaetke LM, Chow CK. Copper toxicity, oxidative stress, and antioxidant nutrients. Toxicology. 2003;189:147–163.