Determination of Total Mercury and Health Risk as Assessment in Wild-grown Bolete Mushrooms from Yunnan Province

PurposesThis study aimed to determine the total mercury (Hg) in common wild-grown bolete mushrooms from Yunnan Province, systematically and analyze the enrichment regularities and accumulation characteristics of Hg in different species as well as different parts of boletes from different geographical origins. Furthermore, the food safety of wild-grown bolete mushrooms was also assessed in order to provide the data basis for the development of wild edible mushroom industry and the risk assessment.Methods Total Hg in caps and stipes of bolete mushrooms were determined by cold-vapour atomic absorption spectroscopy and direct mercury analyzer. The differences and accumulation characteristics of total Hg in different species and different parts of the bolete mushrooms were analyzed based on the values of Hg cap to stipe concentration quotient (QC/S). The food safety of the wild-grown bolete mushrooms from Yunnan Province was evaluated according to the national food safety standards in China and limit contaminants in food (GB 2762-2012) and Hg provisionally tolerable weekly intake (PTWI) recommended by the United Nations Food and Agriculture Organization and the World Health Organization (FAO/WHO).Results The results showed that Q(C/S) values were arranged from 0.3 to 8.8 and the values of 95% samples were greater than or equal to 1, it demonstrated that the accumulation ability of Hg in caps was stronger than that in stipes in most of the bolete mushrooms. The total Hg contents of most of the test bolete samples were higher than the standard GB 2762-2012 (Hg ≤ 0.1 mg/kg). Compared with the PTWI values in adults (60 kg), the amount of Hg presented in a dose of 300 g (average quantity per week) fresh bolete mushrooms was lower than the acceptable intake except the Boletus edulis, Boletus aereus and Boletus tomentipes samples which collected from Dayingjie, Yuxi in 2013, Yongren, Chuxiong in 2012 and Xinping, Yuxi in 2014, respectively, It meant that most of the tested samples did not present health risk to a consumer.Conclusion There were significant differences in total Hg contents in different samples and a few samples were higher than the standard with potential risks.