HUMAN HEALTH RISK ASSESSMENT OF HEAVY METAL CONTAMINANTS IN TABLE SALT FROM NIGERIA

Abstract

Table salt has continue to be an important part of human diet in many households around the world. Table salt is used for food flavouring, pickling, curing and in several industrial purposes. Therefore, the present of contaminants in table salt portends significant risk to human health. The study is aimed at investigating the concentration of heavy metals and human health risk associated with consumption of table salt in Nigeria. Four refined table salt samples (A, B, C, D) and four samples of unrefined table salt (E, F, G, H) were analysed for the concentration of copper (Cu), lead (Pb), iron (Fe), Cadmium (Cd) and arsenic (As) using atomic absorption spectrometry. The United State Environmental Protection Agency (USEPA) methods were used to estimate hazard indices and cancer risks associated with consuming table salt with these elements. Results indicated heavy metal concentrations were significantly higher in unrefined table salt than refined table salt, The estimated daily intake values of Cu, Fe, and Cd were lower than the established provisional tolerable daily intake. The hazard indices did not exceed 1 in all samples of refined and unrefined table salts. However, higher values of HI of Pb, Cd  and As were noted in unrefined table salts. The carcinogenic values of As in refined salt sample B and C and all unrefined table salts were higher than the stipulated one in one million chances which implies that carcinogenic effects were more likely due to consumption of 6.35g/day of salt samples with those contaminants.