Impact of geological origin on trace element composition of edible mushrooms

Abstract

This study aims to examine elements detected in edible mushrooms grown in two geochemically different regions in Finland. One study area lies in the main sulphide ore belt of Finland and is characterised by high metal concentrations in the soil. The reference area with low concentrations of the elements is located in the granitoid complex area of central Finland. Two common mycorrhizal species of mushrooms were analysed— Boletus edulis (cep) and Lactarius trivialis (trivial milk-cup). The concentrations of 33 elements were measured by inductively coupled plasma-mass spectrometry (ICP-MS) after nitric acid dissolution. Soil samples from the habitat were analysed for total and bioavailable fractions. Both mushroom species growing in the main sulphide ore belt were enriched in Ba, Cu, Ni, Zn, and Ag as compared to those growing in the reference area. Thus, the influence of natural geochemistry on the trace element concentrations of the studied mushrooms seems to be evident. This finding leads to the conclusion that inclusion of geographically linked information in food composition databases would enhance their value and allow better utilisation in applied studies.