Levels of some trace heavy metals and fat content in commercially available milk brands in Addis Ababa, Ethiopia

Abstract

The present study analyzed six pasteurized milk brands for their trace heavy metal concentrations and fat contents. The concentrations of Zn, Cu, Cr, Cd, Pb, and Ni were determined by flame atomic absorption spectrometry. The acid digestion method was employed and its validity was checked by recovery test and a good percentage recovery was obtained. Zinc in the different milk brands studied was found to be 1.93 - 3.31 µg/g. The trace metals Cu, Cr, Cd, Pb, and Ni were too low to be detected in all the milk samples. A statistical analysis of variance (ANOVA) at 95% confidence level (p > 0.05) showed that there is no significant difference in the mean concentrations of zinc among the milk brands. The results were also compared with international maximum permissible limits and the concentrations were within the safe limits for human consumption. The fat content of each milk brand was determined and found to be 2.4 - 3.0%. ANOVA at 95% confidence level (p > 0.05) indicated that there is no significant difference observed in the mean fat content among all the milk brands. The fat contents determined were also comparable with the reported values in the literature.