Wild bilberries – Superfood or health risk

Abstract

Wild bilberries (Vaccinium myrtillus L.) were collected from 23 sites in Finland, dried, ground, homogenized and pressed into pellets. The pellets were irradiated in air with a 3 MeV proton beam from the Åbo Akademi MGC-20 cyclotron. The induced X-rays were measured, and elemental concentrations were calculated from the peak areas in the spectra. Elemental concentrations for K, Ca, Mn, Fe, Cu, Zn, Rb, and Sr were found to be above the detection limit of the method. A special focus was set on the high concentration of Mn (27 ± 16 µg/g). Already by consuming 100 g of fresh wild-grown bilberries the Recommended Dietary Allowance value for an adult male was exceeded. A child of 4–8 years old will reach the Tolerable Upper Intake Level of Mn (3 mg/day) by eating somewhat more than 100 g of bilberries in a day. In addition, the regional differences in elemental concentrations were found to be higher than earlier reported. The activity concentrations of Cs-137 in some of the bilberry samples were also measured and the equivalent dose to a person that annually consumes 2 kg of bilberries was found negligible (about 1 µSv).