An assessment of some heavy metals concentrations in lettuce in irrigated with waste water in Tamale Metropolis in Ghana has been carried out. Analysis of water and lettuce samples revealed that the mean concentrations of Fe, Mn, Cu, Zn, Cd and Pb in lettuce were 0.436, 0.345, 0.068, 0.017, 0.04 and 0.038 mg/L and 0.167, 0.163, 0.104, 0.127, 0.142 respectively. With exception of Mn and Cd, the concentrations of heavy metals in the irrigation water, irrigated soils and irrigated lettuce, were within the FAO recommended levels. The mean concentrations of nutrients (NO 3 -N, SO 4 and PO 4 -P) in the wastewater-irrigated lettuce, and well water-irrigated lettuce were 15.36, 0.88, 0.28 and 19.09, 1.117, 0.0573 respectively. Though, heavy metals concentrations in the lettuce were low, regular monitoring are required to prevent heavy metal accumulation with their attendant health implications in the consuming public.

Mineral element compositions of Baobab fruit and seed have been determined using Instrumental Neutron Activation Analysis. Total of 18mineral elements were determined of which 10 are not normally reported using other methods. The concentrations of heavy metals were: Arsenic < 0.06 and < 0.04, Mercury < 0.04 and < 0.04 Hg and Cadmium < 0.08 and < 0.04 respectively for the seeds and the fruit. The average concentration of trace elements in the seed were; Aluminium (11.50 μg/g), Barium (17.3 μg/g), Bromine (2.45 μg/g), Cobalt (0.07 μg/g), Copper (28.6 μg/g), Iron (<42 μg/g), Iodine (<0.04 μg/g), Manganese (17.7 μg/g), Sodium (23.53 μg/g), Vanadium (0.035 μg/g), and Zinc (12.06 μg/g), while the average concentrations of Aluminium (27.74 μg/g), Barium (13.10 μg/g), Bromine (3.01 μg/g), Cobalt (0.08 μg/g), Copper (14.9 μg/g), Iron (26.05 μg/g), Iodine (0.27 μg/g), Manganese (7.05 μg/g), Sodium (52.06 μg/g), Vanadium (0.08 μg/g), and Zinc (0.79 μg/g) were determined for the dried fruit pulp. The mineral concentrations of the baobab fruit and seed were characterized with high concentration of potassium, calcium, magnesium and substantive amount of chlorine [K (21350 μg/g), Ca (3170 μg/g), Mg (2310 μg/g) and Cl (211 μg/g), for the fruit pulp and K (12240 μg/g), Ca (2360 μg/g), Mg (4720 μg/g) and Cl (88.6 μg/g), for the seed]. The fruits and seeds present useful source of mineral needs for the indigenous African community where the trees are found and may be recommended as food supplement due to high content of calcium, magnesium and potassium.

Instrumental neutron activation analysis using the single-comparator method has been used for the multielement determination of essential elements in two main types of Pito brewed locally in Ghana. The precision and accuracy of the analytical method was validated and found to be within 10%. In all, eight different brands of Pito depending on the type of cereal crop used in brewing were analyzed for 13 different elements (Al, As, Ba, Cl, Co, Cu, Fe, K, Mg, Mn, Na, Si, and Zn). It was observed that all brands were particularly enriched in nutrient elements Cl, Mg, and K. The rest were generally found in varying concentrations. As these elements are bioavailable in natural form, perhaps in combination with organic constituents, they are likely to be easily digested and assimilated by the human body. Arsenic, a toxic element, was found in insignificant amounts suggesting that it was within safe limits.