Investigation of heavy metals in selected local spices consumed in Ethiopia
Zemenay Zewdu Aberie, Fikirte Zewdu Sallilh, Molaligne Medfu Tarekegn
Abstract
In Ethiopia, Natural food spices such as sweet basil (Ocimum basilicum L.), Black Cumen (Nigella sativa) and Tenadam (Ruta chalepensis) are the most commonly used spices to improve its colour, aroma, palatability and acceptability of food. They contain a significant quantity of trace metals. These trace metals in spices and medicinal plants play an important role in living cells while other metals are harmful. Knowing the composition of trace metals in foods is important because of their essential or toxic in human health. This study focuses on the determination of heavy trace metals (Zn, Cu, Fe, Cd, and Pb) from Ocimum basilicum L., Nigella sativa, and Ruta chalepensis cultivated in Ethiopia North Gondar administrative Zone particularly, Koladiba, Takusa, and Chuahit were determined using FAAS. The result showed that the concentration of Zn, Cu, Fe, Cd, and Pb in three cultivars of Nigella sativa was 9.07 ± 0.055, 2.83 ± 0.021, 5.55 ± 0.019, 0.80 ± 0.087 and 5.23 ± 0.082 mg/100 g, respectively. In Ocimum basilicum L. was 8.61 ± 0.067, 3.58 ±0.021, 5.55 ± 0.019, 0.606 ± 0.0015, and 3.33 ± 0.0082 mg/100, respectively. Similarly in Ruta chalepensis were 9.38 ± 0.0705, 9.38 ± 0.021, 6.66 ± 0.033, 0.707 ± 0.0017 and 2.85 ± 0.0014 mg/100, respectively. In this work, Nigella sativa, Ocimum basilicun, and Ruta chalepensis are good sources of Zn, Cu, Fe, and the number of toxic metals Cd and Pb are below the permissible limit as compared to the value reported in WHO. Therefore, a non-carcinogenic health risk to the consumer associated with the consumption of this spices preparation marketed in study areas.