A review of trace element concentrations in edible mushrooms

Wild growing mushrooms have been a popular delicacy in many countries. Some species, mainly from genera Agaricus, Macrolepiota, Lepista and Calocybe accumulate high levels of cadmium and mercury even in unpolluted and mildly polluted areas. The concentrations of both metals and also of lead increase considerably in the heavily polluted sites, such as in the vicinity of metal smelters. The usual concentrations of the three deleterious metals are presented in tables for 25 species consumed within Europe. A brief overview of 12 other metals in mushrooms is also given. Present knowledge of metal speciation in mushrooms is limited as is knowledge of their bioavailability in man. Thus, consumption of the accumulating species should be restricted. Semimetals selenium, arsenic and antimony do not occur in undesirable levels. The cultivated species, especially the common mushroom (Agaricus bisporus) and oyster mushroom (Pleurotus ostreatus) contain only low levels of the trace elements. Very scarce information is available on metal losses during preservation and culinary treatment of mushrooms.