Food toxicity assessment of selected canned foods in Nigeria

Food toxicity assessment was made for frequently consumed canned foods in Nigeria in order to estimate potential human health risks associated with their consumption. Levels of heavy metals (Pb, Cd, As, Fe, Mn and Zn), Nitrate and Nitrite, pH and salt were assessed in randomly purchased samples from groceries stores to represent what is readily available on the market. Nitrates and nitrites were assessed using a Perkin-Elmer spectrophotometer while heavy metal levels were determined using Atomic absorption spectrophotometer. Human health risk was estimated using standard indices; estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI) and dietary exposure (DE). Results showed varying concentrations of nitrates, nitrites, heavy metals, in all the canned food categories but the level of salt and pH seemed constant. Nitrate, Fe and Cd in all the canned food categories exceeded recommended limit set by EU. Health risk estimations showed EDI values for Cd in all the canned food categories above the tolerable daily intake, while DE for Fe in canned sweet corn, Fe, Zn and Pb in canned beans/peas had values above recommended limits. THQ values for all the canned foods were above 1 in the canned beans/peas while HI was above 1 in the canned fish category. The study revealed the potential for Cd toxicity and risk of non-carcinogenic health effects from canned beans/peas consumption. Constant monitoring of canned foods is therefore imperative considering the growing demand for canned products due to changing lifestyle.