IOSR Journal of Applied Chemistry (IOSR-JAC) e-ISSN: 2278-5736.Volume 10, Issue 7 Ver. III (July. 2017), PP 11-15 www.iosrjournals.org DOI: 10.9790/5736-1007031115 www.iosrjournals.org 11 |Page Evaluation of Heavy Metals and Nutrients in Powdered Milk Marketed Within Kaduna Metropolis, Nigeria * F. Abubakar 1 , L. Salihu 2 1 Department of Applied Science, College of Science and Technology, Kaduna Polytechnic 2 Department of Chemistry, Nigerian Defence Academy, Kaduna Corresponding Author: F. Abubakar Abstract: The heavy metals (Pb and Cd) and essential elements (Cu, Fe, Ca and K) of five selected commercial brands of powdered milk produced in Nigeria and marketed within Kaduna metropolis were analyzed Atomic Absorption Spectrophotometer and Flame photometer. The protein contents were also determined using Kjeldahl titration. The representative powdered milk samples were coded as M1, M2, M3, M4 and M5. The results showed that the highest concentration of lead was recorded inM2 (0.116 mg/kg) and the lowest inM1 (0.068 mg/kg). Other values of lead obtained were 0.083 mg/kg and 0.097 mg/kg forM4 and M3 respectively. The highest concentrations of copper was recorded inM5 (0.278 mg/kg) and the lowest was recorded inM4 (0.045 mg/kg). Other values obtained were 0.2233 mg/kg, 0.2204 mg/kg, and 0.2156 mg/kg forM1, M2 and M3 respectively. The highest concentration of iron was recorded inM4 (4.970 mg/kg) and the lowest inM1 (1.119 mg/kg). Other values obtained were 1.188 mg/kg, 1.491 mg/kg and 1.790 mg/kg forM2, M3 and M5 respectively. The concentration of zinc in the milk samples ranged from 2.575 - 3.797 mg/kg. Cadmium and Mercury were however not detected in any of the samples analyzed.The amount of the protein in the samples ranged from 22.10% - 27.20%. The concentrations of heavy metals and essential elements in the various brands of powdered milk samples were statistically significant at (P<0.05) except for lead, zinc and potassium which were not significant (P<0.05). The results obtained show that the brands of milk are good sources of mineral nutrients and the highly toxic metals like mercury and cadmium were below detection limit. Furthermore, the essential minerals such as calcium, potassium and chromium did not exceed their permissible limit and the recommended dietary allowance. Keywords: Powdered milk, Heavy metals, Flame photometer, atomic absorption spectrophotometer, Kaduna --------------------------------------------------------------------------------------------------------------------------------------- Date of Submission: 05-07-2017 Date of acceptance: 27-07-2017 --------------------------------------------------------------------------------------------------------------------------------------- I. Introduction The issue of pollution is central in man's quest to develop himself. Industrial activities result in redistribution of mineral substances from their natural deposits into foods and beverages [1]. Many of these mineral elements or substances undergo chemical changes and are transformed either in solution or in finely dispersed form through many channels to the food chain. High levels of these materials in the environment facilitate their entry into the food chain thereby increasing their possibility of having toxic effects on humans and animals. The phrase 'chemical contamination' is used to indicate situations where chemicals are either present or are at higher concentrations than they would naturally have occurred [2].Chemical contaminants in milk comprise of chemical hazards that may be introduced during milk production, dairy processing or packaging. Drugs, heavy metals, radionuclides, mycotoxins and pesticides are chemical contaminants that can be found in animal feed and on consumption as residues in milk [3]. Heavy metals are persistent as contaminants in the environment and are at the fore front of dangerous substances causing health hazards in human. Industrial and agricultural activities have resulted in an increased concentration of heavy metals in air, water and soil. They are subsequently taken up by plants or animals and they eventually find their ways into the food chain [4, 5]. Although the amount of heavy metals in uncontaminated milk is admittedly low, their concentration may be significantly altered and magnified through manufacturing and packaging processes [5]. Heavy metals are non bio-degradable substances and they accumulate in the environment up to a considerable extent. They are bio-transferred, bio-accumulated and bio-magnified in food chains and food webs. Animals like cows, sheep, and buffalos feed on grasses and plants which may contain pollutants like heavy metals which may either accumulate in their tissues causing various health hazards or transferred to their consumers. Although, toxic metals by and large remain in ground water and soil, they tend to accumulate to maximum and toxic levels in human and animal tissues feeding from water and soil sources [6]. Living organisms normally need some of these heavy metals as essential metals up to certain limits and in case of increased accumulation it will lead to severe fatal effects [6]. Toxic metals are generally not removed even after