Bioconcentration potential and contamination with mercury of pantropical mushroom Macrocybe gigantea

The mushroom Macrocybe gigantea collected from the native stands in the Yunnan Province of China can be considered a species that efficiently bioconcentrates mercury (Hg) because the values of the bioconcentration factor (BCF) calculated for this element were well above unity, i.e., for caps, the BCF ranged from 4.8 to 24 and, for stipes, from 3.6 to 18. The Hg content of the composite samples of caps of the fruit bodies collected in the wild ranged from 0.48 to 1.78 mg kg(-1) dry matter and of stipes from 0.36 to 1.70 mg kg(-1) dry matter, whereas 0.37 and 0.25 mg kg(-1) dry matter were observed for farmed specimens. M. gigantea, because of a large biomass of the fruit bodies that emerge in a cluster, is an important food item in Yunnan, but knowledge on mineral composition and content of this species is largely absent. This study estimated the lifetime average daily dose intake of Hg through mushroom as well as the incremental lifetime cancer risk and non-cancer health hazard to consumers of this mushroom.