The aim of this study was to evaluate the contamination of six edible wild species of mushrooms (Boletus pulverulentus, Cantharellus cibarius, Lactarius quietus, Macrolepiota procera, Russula xerampelina and Suillus grevillei) by heavy metals (Hg, Cd, Pb, Zn, Cu, Ni, Cr, Co, Mn and Fe). Mushroom samples were collected from sites contaminated by emissions from mining and processing of polymetallic ores in operation during the period 1969–1993 in Rudňany, southeast Slovakia. The four study sites spanned up to a 5-km distance from the emission source. The collected mushroom samples were analyzed using Flame Atomic Absorption Spectrophotometry and/or Flame Atomic Absorption Spectrophotometry with graphite furnace. Mercury, Cd and, in some samples, also Pb present the highest risks in terms of contamination of the food chain following subsequent consumption. The content of two metals in the dry matter (dm) of the mushrooms exceeded the limits set by the European Union (EU; Cd: 0.5 mg/kg dm, Pb: 1.0 mg/kg dm). The highest mean contents of the eight metals recorded for S. grevillei were 52.2, 2.15, 107, 104, 2.27, 2.49, 81.6 and 434 mg/kg dm for Hg, Pb, Zn, Cu, Ni, Cr, Mn and Fe, respectively. The highest content of Cd was recorded in M. procera (3.05 mg/kg dm) and that of Co in L. quietus (0.90 mg/kg dm). The calculated weekly intake for Hg, Pb and Cd shows that regular consumption of mushrooms from the studied area poses risks to human health.

Contamination of soil by toxic elements is a global issue of growing importance due to the increased anthropogenic impact on the natural environment. Conventional methods of soil decontamination possess disadvantages in forms of environmental and financial burdens. This fact leads to the search for alternative approaches of remediation of contaminated sites. One such approach includes phytoremediation. Phytoremediation advantages consist of low costs and small environmental impact. Several fast-growing energy plant species are suitable for phytoremediation purposes. Our article focuses on the phytoremediation potential of energy woody crops of Salix and Populus, and energy grasses Miscanthus and Arundo, which are grown primarily for biomass production. This approach links the environmentally friendly and economically less demanding remediation approach with the production of the local sustainable form of energy that decreases dependency on external energy supplies. Energy plants are able to provide high biomass yields in a short period of time, they are resistant against abiotic stress conditions and have the ability to accumulate toxic substances, thus helping to restore the desirable soil properties. The phytoremediation research is very interdisciplinary in its nature. In order to implement phytoremediation practices together with bioenergy successfully, it is crucial to involve site owners, local people, farmers, technology providers and consultants, remediation experts, sustainability assessors, regulatory agencies and certification bodies, biorefineries, financial sponsors, NGOs and other voluntary organizations. Some disadvantages and challenges of phytoremediation are also indicated.

The contamination level of 92 samples (12 species) of wild edible mushrooms and underlying substrates with heavy metals (Cd, Cu, Hg, Pb and Zn) in the Slovak Paradise National Park that borders with a region of historical mining and processing of polymetallic ores, were determined. The collected samples were analyzed using of atomic absorption spectrophotometry. The metals were determined separately in hymenophore (H) and rest of fruit bodies (RFB). Bioaccumulation factor as well as ratio of metal content in H and RFB were calculated. Cadmium and lead contents in hymenophore exceeded statutory limits of the EU (Cd: 0.5 mg/kg dry weight (dw), Pb: 1.0 mg/kg dw) for edible mushrooms in 96% and 83% of the samples, respectively. The risk from the consumption of the collected mushroom species was calculated based on the provisionally tolerable weekly intake (PTWI) values, and the highest health risk arising with consumption of particularly Macrolepiota procera, Marasmius oreades and Russula vesca from the observed area was demonstrated. It was shown that average weekly consumption of tested mushrooms species results the threat of exceeding of PTWI limits in the case of cadmium values (by 164%, 86% and 4% of PTWI for M. oreades, R. vesca and R. puellaris, respectively) and of mercury (by 96% of PTWI for M. procera) but not lead.

Three edible mushroom species (Imlera badia, Boletus subtomentosus, Xerocomellus chrysenteron) sampled in 60 different localities of Slovakia were evaluated to determine health risks (associated with mercury content) arising from their consumption. Total content of mercury in soil and mushroom samples was determined by an AMA-254 analyzer. Soil pollution by mercury was evaluated by contamination factor (C_f), pollution load index (PLI), and geoaccumulation index (I_geo). Bioaccumulation factor (BAF), translocation factor (Qc/s), provisional tolerably weekly intake (%PTWI), estimated daily intake (EDI), and target hazard quotient (THQ) were used to describe and compare uptake and transition abilities of mushrooms, and the health risk arising from mushroom consumption. Mercury content in soil significantly influences the content of mercury in mushroom fruiting body parts. Caps and stipes of Boletus subtomentosus were found to be the best mercury accumulator. According to the EDI, consumption of the evaluated mushroom species represents a serious threat for adults and children. The lowest values of THQ were found for Xerocomellus chysenteron.