Concentration of mercury in edible fungi of the genus Clitocybe from different parts of Croatia

U ovom radu utvrđivana je kontaminacija, bio koncentracija i distribucija žive u samoniklim gljivama roda Clitocybe, vrstama Clitocybe nebularis i Clitocybe inversa, uz procjenu i rizik unosa žive u ljudski organizam putem prehrambenih proizvoda. Uzorci gljiva i gornji horizont tla prikupljeni su na osam nezagađenih i geografski udaljenih područja kako bi se spriječila lokalna ili regionalna emisija žive. Koncentracija žive u klobuku gljiva varirala je od 0,183 ± 0,025 do 0,621 ± 0,745 mg kg-1 suhe tvari, u stručku od 0,071 ± 0,012 do 0,312 ± 0,208 mg kg-1 suhe tvari. Raspon koncentracija žive u gornjem horizontu tla manji je u odnosu na anatomske dijelove gljive, a vrijednosti su se kretale od 0,012 ± 0,005 do 0,025 ± 0,006 mg kg-1 suhe tvari. Istraživanjem je utvrđena niska koncentracija žive u gljivama vrste Clitocybe, kao i u gornjim horizontima tla prikupljenih iz nezagađenih područja. Klobuk u odnosu na stručak u obje analizirane vrste gljiva akumulira višu koncentraciju žive. Vrsta Clitocybe nebularis pokazala se vrlo dobrim bio akumulatorom žive, sa vrijednostima bio koncentracijskog faktora od 10,42 do 24,26. Istraživanjem je utvrđeno da vrste Clitocybe nebularis i Clitocybe inversa ne predstavljaju opasnost unosa žive u ljudski organizam prilikom konzumacije istih.The contamination, bio-concentration and distribution of mercury (Hg) in wild mushrooms of the genus Clitocybe such as Clitocybe inversa, Clitocybe nebularis were studied, and the possible dietary intake and risk for human consumers in Croatia was estimated. Mushrooms, together with the associated forest topsoils were collected from 8 unpolluted and geographically distant areas, far from local or regional emission sources. The Hg contents were in the range 0.183 ± 0.025 to 0.621 ± 0.745 mg kg−1 dry matter in caps and 0.071 ± 0.012 to 0.312 ± 0.208 mg kg−1 in stems. The corresponding topsoil concentrations varied over a relatively narrow range between sites, from 0.012 ± 0.005 to 0.025 ± 0.006 mg kg−1 dry matter. Overall, the study results showed low levels of mercury both, in edible Clitocybe mushrooms and forest topsoils from background (unpolluted) forested areas in Croatia. The morphological distribution showed considerably greater concentrations of mercury in the caps relative to the stems. C. nebularis showed good ability to bioconcentrate Hg, with bioconcentration factors (BCF) values in the range 10.42 to 24.26. The data suggests that Clitocybe mushrooms from unpolluted areas in Croatia can be considered as a low risk food from the point of view of the tolerable Hg intake