Dietary exposure and risk characterization of selected toxic metals in crude palm oil (Elaeis guineensis Jacq) from six states in Niger Delta, Nigeria

Abstract

The increase in toxic metal (TM) contamination in crude palm oil (CPO) due to anthropogenic activities, method of processing and handling makes it necessary to assess the contents of metals of toxicological interest to ensure safety. The contents of TMs [lead (Pb), cadmium (Cd), chromium (Cr), nickel (Ni) and arsenic (As)] were quantified in CPO samples locally produced from six selected states in Niger Delta, Nigeria using atomic absorption spectrophotometer. The TM contents and dietary intakes were compared with permitted limits of international agencies such as the European Food Safety Authority (EFSA) and Joint FAO/WHO Expert Committee on Food Additives (JECFA). The TM contents exceeded the permissible limits of JECFA with Cr in Akwa Ibom State samples (3.08 mg kg-1) being the highest. The dietary monthly intake of Cd for consumption of 25 g day-1 of CPO for adults and children were 40.36 µg kg-bw-1 month-1 (161%) and 91.6 µg kg-bw-1 month-1 (366%), respectively. The margin of exposure (MOE) values of Pb due to consumption of CPO ranged from 1.39 to 3.83 (nephrotoxic effects) and 3.32 to 9.12 (cardiotoxic effects) for adults, and 0.49 to 1.34 (neurotoxic effect), 0.61 to 1.69 (nephrotoxic effects) and 0.61 to 4.01 (cardiotoxic effects) for children. Furthermore, MOE values of inorganic arsenic (iAs) for carcinogenic effects due to consumption of CPO for adults and children ranged from 0.32 to 26.53 and 0.14 to 11.69, respectively. The results highlight the necessity to set up monitoring program for TMs in CPO to reduce exposure level.