Mercury contamination of fungi genus Xerocomus in the Yunnan province in China and the region of Europe

Abstract

This article presents the results of the study on accumulation, distribution, contamination and probable dietary intake of total mercury (THg) in fruiting bodies of several species of Fungi genus Xerocomus, which emerged in the circum-Pacific mercuriferous belt region in southwestern China in Yunnan and beyond of the mercuriferous belts in the region of Europe. The mushrooms X. puniceus (Boletus amygdalinus), X. spadiceus (Boletus ferrugineus) and X. versicolor (X. rubellus) were from the Yunnan land, and X. badius (Boletus badius) was from the region of Europe in Belarus and X. badius, X. chrysenteron, X. ferrugineus, X. versicolor (X. rubellus) and X. subtomentosus from Poland. The THg in the fungal and soil materials was determined using validated method by cold-vapour atomic absorption spectroscopy. Estimated was also probable dietary intake and health risk from THg in Xerocomus spp. examined by consumers. The data showed that THg content of Xerocomus spp. emerged in the European localizations in Poland and Belarus is at an order of magnitude lower level than determined in samples from the Yunnan Province. A reason for an elevated content of THg in mushrooms from Yunnan can be related to abundance of Hg in the geochemical background of soils there. The assessed doses showed that a single meal composed of 300 g of fresh fruiting bodies of X. spadiceus from the Wuding localization in Yunnan in China if consumed once a week will provide THg at dose close to the provisional tolerable weekly intake (PTWI) value set for THg, while doses will be lower for all other localizations in Yunnan and Europe. In the Wuding localization in Yunnan a frequent consumption of X. spadiceus in volume exceeding 300 g of fresh fruiting bodies per week will provide THg at a dose exceeding the value of PTWI.