Metal Contents, Bioaccumulation, and Health Risk Assessment in Wild Edible Boletaceae Mushrooms

Eight wild edible Boletaceae mushrooms (227 samples) and their soils were collected from 40 locations, Yunnan province, China. Four essential metals (Fe, Mg, Zn, and Cu) and 2 toxic metals (Pb and Cd) were determined. The results showed that Boletaceae mushrooms have abundance of 4 essential metals. The highest Pb mean value was 0.70 mg/kg DW, lower than legal limits, but Cd contents significantly exceeded legal limits. Generally, bioconcentration factor (BCF) indicated that Zn and Cu were easily bioaccumulated by mushrooms. However, the BCFCd of Boletus griseus reached to 6.40. Target hazard quotients showed Cd was the main risk metal in Boletaceae mushrooms. The metal compositional variability and the similarity of metal contents were further determined by principal component analysis. Regression model analysis indicated that Cd contents in mushrooms were positively correlated with soil Cd contents, and negatively correlated with soil pH, except for the samples of Boletus bicolor. Practical Application The consumption of wild-grown mushrooms is increasing. However, wild edible mushrooms usually accumulate high contents of metallic elements, including high levels of potentially toxic metals, compared with cultivated species. Yunnan province, located in southwestern China, is a specific region abundant in wild mushrooms and over 880 species are identified as edible. Nevertheless, the reports of the metals in mushrooms are still limited, compared to that of central and Eastern Europe. This study can provide information for assessment of the nutritional values of these mushroom species, as well the potential health risks associated with the heavy metals.