Investigation of some heavy metals in kefirs sold in afyonkarahisar province with ICP-OES

This study was conducted to determine the levels of certain heavy metals in kefir samples belonging to five different brands sold in Afyonkarahisar province and to evaluate these values in terms of human health. Kefir is a dairy product whose consumption is steadily increasing due to its probiotic content and functional properties. However, factors such as environmental pollution and production and packaging processes can lead to heavy metal contamination in these products. Therefore, regular analyses are of great importance in terms of food safety. Within the scope of this study, composite samples obtained from kefir products of each brand were analyzed using the ICP-OES (Inductively Coupled Plasma - Optical Emission Spectrometry) method. Standard acid digestion was applied in sample preparation, and the concentrations of eight different heavy metals, namely Cr, Zn, Pb, Cd, Fe, Cu, Hg, and As, were investigated. The results obtained were evaluated by comparing them with the limit values determined by the Turkish Food Codex and international authorities. As a result of the analyses, it was determined that the levels of Cu and Zn were significantly elevated in some samples, whereas the levels of other elements were found to be below the detection limits. This finding underscores the necessity of continuous monitoring and control of certain kefir brands, especially in terms of Cu and Zn concentrations. The data obtained indicate that, in general, the kefir samples are considered safe for consumption. However, it is also emphasized that there is a risk of contamination in the production chain, which requires ongoing surveillance and the implementation of necessary control mechanisms. This study is significant as it represents one of the first scientific screenings of the heavy metal content in kefir products offered for sale in Afyonkarahisar province. Furthermore, it has been concluded that monitoring metal contamination in fermented dairy products, such as kefir, may contribute positively to public health.