Exploring metal bioaccumulation ability of boreal white-rot fungi on fiberbank material

Fiberbanks are organic-rich sediment deposits in aquatic environments, primarily formed through historical pulp and paper mill activities. These deposits consist of wood-derived fibrous materials and are contaminated with potentially toxic elements (PTEs) such as vanadium, chromium, cobalt, nickel, copper, zinc, arsenic, cadmium, and lead. The leaching of these contaminants into surrounding waters poses significant environmental and health risks, impacting aquatic ecosystems and potentially entering the food chain. Effective remediation of fiberbanks is crucial, particularly in Sweden and other regions with extensive wood-pulping industries. This study aims to evaluate the bioaccumulation capacities of 26 native Swedish white-rot fungi (WRF) species for the remediation of PTEs in fiberbank material. Fiberbank samples were collected from Sundsvall's Bay in the Baltic Sea, while the fungal species were isolated from boreal forests in Västernorrland, Sweden. The fungi were cultured on Hagem agar medium with sterilized fiberbank material as the substrate. After two months, fungal biomass was analyzed for PTE uptake using inductively coupled plasma-mass spectrometry (ICP-MS). The results revealed significant variability (<i>p</i> < 0.001) in PTE uptake among fungal species. <i>Phlebia tremellosa</i> consistently demonstrated the highest bioconcentration factors for analyzed elements, with values for V (0.39), Cr (0.10), Co (1.81), Cu (1.54), Pb (1.65), Ni (1.28), As (0.83), Zn (3.61), and Cd (5.56). Other species, including <i>Laetiporus sulphureus</i> (0.09-4.78), <i>Hymenochaete tabacina</i> (0.08-4.52), and <i>Diplomitoporus crustulinus</i> (0.08-4.48), also exhibited significant bioremediation potential. These findings highlight the potential of native WRF species for PTEs remediation in fiberbanks and provide a foundation for mycoremediation strategies in contaminated environments.