Determination of content of cadmium and health risk assessment in wild- grown bolete mushrooms from Yunnan province

17 species of wild- grown edible bolete mushrooms and the topsoil which collected from different regions of Yunnan province were used as the research objects.The content of toxic heavy metal cadmium in boletes was determined by ICP- AES. The enrichment regularities of Cd in different species of bolete mushrooms and the relationship of Cd contents between boletes and the topsoil samples were analyzed. The Cd exposure risk of the wild- grown bolete mushrooms from Yunnan was evaluated according to the GB2762-2012 and Cd Provisionally Tolerable Weekly Intake( PTWI) recommended by the FAO / WHO. The results showed that,there were obvious differences in enrichment of Cd contents in different species of mushroom samples,the Cd content in caps and stipes were in the range of 3.03~18.89,2.13~10.03 mg / kg dry weight( dw),respectively.Except the Pulveroboletus retipes,the Cd content ratios of cap and stipe(Q_((C/S))) were greater than 1.It demonstrated that the accumulation ability of Cd in caps was stronger than that in stipes of the bolete mushrooms.The bioaccumulation factor of caps and stipes of different bolete mushroom samples were in the range of 0.08 ~ 1.55 and 0.06 ~ 0.71,respectively. The contents of Cd in most boletes and the topsoil were positively related which showed that the Cd accumulation degree was related to the species and soil background.After analyzing the edible safety of boletes,it showed thecontents of Cd in 17 species of wild- grown bolete mushrooms exceed the Cd limited standard which prescribed by GB2762-2012.If adults( 60 kg) eat 500 g fresh bolete mushrooms a week,Cd intakes in part of boletes would be higher than the PTWI standard which shows that these mushrooms couldn't be ate for long- term or excessively.