Trace elements and rare earth elements in honeys from the Balkans, Kazakhstan, Italy, South America, and Tanzania

Honey is a very unusual food - a natural substance produced by bees from the nectar or secretion of plants and elaborated by the bees themselves. Differences in trace elements and rare earth elements (REEs) are related to botanical and geographical origin, and, as such, honey could be a suitable indicator for metal occurrence in the environment within the bee forage area. A total of 40 metals were analyzed by inductively coupled plasma-mass spectrometry in multi-floral honey samples from different geographical areas. The highest levels of trace elements and REEs were found in honey from Tanzania, while lower concentrations were recorded in Italian, Kazakhstan, the Balkans, and South American honeys. Tanzanian honey is of interest due to its different content of metals, related to the peculiar lithology and the mineral resources of this country. Rubidium and aluminum were the most represented nonessential elements, while manganese, iron, zinc, and copper registered the highest values of the essential elements. Very low concentrations were found for the toxic elements lead, cadmium, and arsenic. The present study showed differences in metal concentrations in multi-floral honey from different countries, confirming the strong influence of the area of origin on the chemical composition of honeys.