An evaluation of the occurrence and trends in 137Cs and 40K radioactivity in King Bolete Boletus edulis mushrooms in Poland during 1995-2019

ASSESSMENT OF DOSES FROM INGESTION OF RADIONUCLIDES 40 K, 137CS, 226RA AND 232TH IN EDIBLE COMMERCIAL MUSHROOMS FROM TAIWAN

This study analyzed activity concentration and annual effective dose of radionuclides 40K, 137Cs, 226Ra and 232Th of 44 mushrooms collected from local markets in Taiwan. The 40K activity concentrations were 1570 ± 150 Bq/kg-dw (Agaricus bisporus) > 1084 ± 183 Bq/kg-dw (Flammulina velutipe) > 736 ± 150 Bq/kg-dw (Lentinula edodes). The activity concentrations of 226Ra were 5.04 ± 2.43, 4.00 ± 2.40 and 3.43 ± 2.69 Bq/kg-dw, and 232Th were 3.96 ± 2.18, 3.86 ± 1.43 and 2.90 ± 1.99 Bq/kg-dw for F. velutipe, L. edodes and A. bisporus, respectively. In seven of the 44 samples, 137Cs activity concentrations were detected, and the samples had an average of 1.55 ± 1.75 Bq/kg-dw. The total annual effective dose ranged from 0.90 to 3.50 μSv/y, with an average of 1.94 ± 0.62 μSv/y at an ingestion rate of 0.235 kg-dw/y.

Activity concentrations and bioconcentration factors (BCFs) of natural radionuclides (40 K, 226Ra, and 232Th) from cultivated substrates to mushrooms

This study examined 42 mushroom samples and corresponding cultivated substrates. The radionuclide activity concentrations and bioconcentration factor (BCF) from substrate-to-mushroom were determined. The substrate activity concentrations were 59.1-727.5, 4.5-37.6, and 4.0-53.0 Bq/kg dw (dry weight) for 40 K, 226Ra, and 232Th, respectively. The average 40 K concentrations were 1546.5, 1115.7, and 749.3 Bq/kg dw; the BCFs were 2.49, 3.56, and 5.58 for A. bisporus, F. velutipes, and L. edodes, respectively. The 40 K concentrations were insignificantly correlated with each species' corresponding substrate concentration. The 40 K BCFs had a significantly negative correlation with the substrate concentration for each species. Each mushroom species' 40 K concentration was almost stable, suggesting that 40 K has a regulated homeostasis for a given species. The average 226Ra concentrations were 5.5, 5.4, and 3.4 Bq/kg dw; the BCFs were 0.58, 0.17, and 0.50 for L. edodes, A. bisporus, and F. velutipes, respectively. The average 232Th concentrations were 4.7, 4.7, and 3.0 Bq/kg dw; the BCFs were 0.50, 0.11, and 0.53 for L. edodes, A. bisporus, and F. velutipes, respectively. The 226Ra and 232Th concentrations in mushrooms had a weak to moderate correlation with the cultivated substrate concentrations. The absorption of the 226Ra and 232Th from substrate-to-mushroom was similar to the hypothesis of the linear model that mushroom concentration yields a positive correlation with substrate concentration.

Exemplifying the “wild boar paradox”: dynamics of cesium-137 contaminations in wild boars in Germany and Japan

Wild boars (Sus scrofa) are notorious for accumulating high contamination levels of 137Cs in their meat. Publicly available data of 137Cs contamination levels in wild boars from 2011 to 2019 were used to determine some radioecological characteristics in Germany (affected by Chernobyl-fallout, 1986) and Japan (affected Fukushima, 2011). The effective half-life of 137Cs in wild boar meat was much longer in Germany (7.3 y) than in Japan (2.6 y), respectively. Wild boars in Germany thus show much more persistent contamination levels than other game or forest animals. This unusual behavior has been termed “wild boar paradox.” In German wild boars, the data sets reveal a distinct geographical and seasonal dependence with higher activity concentrations in winter than in summer. In Japan, contamination levels only exhibit a distinct decline behavior.

Rare Earth Elements in Boletus edulis (King Bolete) Mushrooms from Lowland and Montane Areas in Poland

Mining/exploitation and commercial applications of the rare-earth elements (REEs: La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) in the past 3 decades have raised concerns about their emissions to the environment, possible accumulation in food webs, and occupational/environmental health effects. The occurrence and distribution of REEs Y and Sc in the fruitbodies of Boletus edulis collected from geographically diverse regions in Poland were studied in 14 composite samples that were derived from 261 whole fruiting bodies. Individual REE median concentrations ranged from 0.4-95 µg kg-1 dry weight (dw). The summed REE concentrations varied widely, with a median value of 310 µg kg-1 dw and a range of 87 to 758 µg kg-1. The Sc and Y median concentrations (dw) were 35 and 42 µg kg-1, respectively. Ce, La, and Nd, with median values of 95, 51, and 32 µg kg-1, respectively, showed the highest occurrence. B. edulis collected from a forested area formerly used as a military shooting range-possibly a historically contaminated site-had an elevated summed REE content of 1796 µg kg-1. REE concentrations were generally low in Polish King Bolete. Dietary intake from a mushroom meal was negligible, posing no health risk to consumers.

137Cs and 40K activity concentrations in edible wild mushrooms from China regions during the 2014–2016 period

Introduction. Contamination by radiocaesium of edible wild mushrooms after major nuclear accidents is a long-lasting process in some regions of the world. Following greater awareness of radioactive pollution in Asia, particularly after the Fukushima accident, this study investigated the radioactivity of 137Cs and 40K contamination in edible wild mushrooms in China. Study objects and methods. The objects of the research were edible wild mushrooms collected during 2014 to 2016, from the Inner Mongolian and Yunnan regions of China. To obtain an insight into any environmental impacts to distant regions of mainland Asia, the mushrooms were analyzed for 137Cs activity. In parallel, the natural activity of 40K was also determined and used to estimate the content of total K. The topsoil underneath the mushrooms was also investigated from a few sites in Bayanhushu in Inner Mongolia in 2015. Results and discussion. The results showed that in 4 to 6 mushrooming seasons after the accident, mushrooms from both regions were only slightly contaminated with 137Cs, which implied negligible consequences. The activity concentrations of 137Cs in dried caps and whole mushrooms in 63 of 70 lots from 26 locations were well below 20 Bq kg–1 dry weight. Two species (Lactarius hygrophoroides L. and Lactarius volemus L.), from Jiulongchi in Yuxi prefecture showed higher 137Cs activities, from 130 ± 5 to 210 ± 13 Bq kg–1 dw in the caps. 40K activities of mushrooms were around two- to three-fold higher. A composite sample of topsoil (0–10 cm layer) from the Bayanhushu site (altitude 920 m a.s.l.) in Inner Mongolia showed 137Cs activity concentration at a low level of 6.8 ± 0.7 Bq kg–1 dw, but it was relatively rich in potassium (40K of 595 ± 41 Bq kg–1 and total K of 17000 ± 1000 mg kg–1 dw). Conclusion. Wild mushrooms from the Yunnan and Inner Mongolia lands only slightly affected with radioactivity from artificial 137Cs. Lack of 134Cs showed negligible impact from Fukushima fallout. Ionizing radiation dose from 137Cs in potential meals was a fraction of 40K radioactivity. The associated dietary exposure to ionizing irradiation from 137Cs and 40K contained in mushrooms from the regions studied was considered negligible and low, respectively. Mushroom species examined in this study are a potentially good source of dietary potassium.

Effect of drying, blanching, pickling and maceration on the fate of 40K, total K and 137Cs in bolete mushrooms and dietary intake

The effects of blanching, blanching and pickling and maceration on the leaching of ¹³⁷Cs and ⁴⁰K from the flesh of three edible bolete mushroom species-Boletus edulis, Leccinum scabrum and Leccinum versipelle-were investigated. Significant (p < 0.05) decreases in activity were observed but varied depending on the treatment. Relative to fresh mushrooms, blanching decreased the activity concentration of ¹³⁷Cs by 15 ± 13%, and of ⁴⁰K, by 16 ± 7%, but blanching and pickling (vinegar) reduced activity more effectively, by 55 ± 8% and 40 ± 20% respectively. The corresponding losses of ¹³⁷Cs and ⁴⁰K through maceration of dried, powdered mushrooms were 38 ± 11% and 35 ± 14% ww, respectively. These results indicate that traditional domestic processing methods may not be as efficient at excluding ¹³⁷Cs radioactivity as shown in some other studies. The activity concentration of ¹³⁷Cs in a typically sized (100 g) portion of a processed mushroom (sourced from nearshore regions of the southern Baltic Sea coast near Gdańsk in 2015) meal was projected to be low, i.e. in the range of 0.51 to 12 Bq kg^-1 ww. The corresponding effective dose of ¹³⁷Cs from blanched, blanched and pickled and macerated mushrooms per capita was also assessed to be low, from 0.001 to 0.010 μSv. Nutritionally, the median concentration of potassium (330 mg) in 100 g portions of blanched or pickled mushrooms would account for around 7% of the adequate adult daily intake.

Radiocaesium in Tricholoma spp. from the Northern Hemisphere in 1971-2016

A considerable amount of data has been published on the accumulation of radiocaesium (¹³⁴Cs and particularly, ¹³⁷Cs) in wild fungi since the first anthropogenically influenced releases into the environment due to nuclear weapon testing, usage and subsequently from major accidents at nuclear power plants in Chernobyl (1986) and Fukushima (2011). Wild fungi are particularly susceptible to accumulation of radiocaesium and contamination persists for decades after pollution events. Macromycetes (fruiting bodies, popularly called mushrooms) of the edible fungal species are an important part of the human and forest animal food-webs in many global locations. This review discusses published occurrences of ¹³⁴Cs and ¹³⁷Cs in twenty four species of Tricholoma mushrooms sourced from the Northern Hemisphere over the last five decades, but also includes some recent data from Italy and Poland. Tricholoma are an ectomycorrhizal species and the interval for contamination to permeate to lower soils layers which host their mycelial networks, results in a delayed manifestation of radioactivity. Available data from Poland, over similar periods, may suggest species selective differences in accumulation, with some fruiting bodies, e.g. T. portentosum, showing lower activity levels relative to others, e.g. T. equestre. Species like T. album, T. sulphurescens and T. terreum also show higher accumulation of radiocaesium, but reported observations are few. The uneven spatial distribution of the data combined with a limited number of observations make it difficult to decipher any temporal contamination patterns from the observations in Polish regions. When data from other European sites is included, a similar variability of ¹³⁷Cs activity is apparent but the more recent Ukrainian data appears to show relatively lower activities. ⁴⁰K activity in mushrooms which is associated with essential potassium, remains relatively constant. Further monitoring of ¹³⁷Cs activity in wild mushrooms would help to consolidate these observations.

Nutritional and Other Trace Elements and Their Associations in Raw King Bolete Mushrooms, Boletus edulis

The occurrence and associations of Ag, As, Ba, Bi, Cd, Co, Cu, Cs, Hg, Ni, Pb, Rb, Sb, Sr, Tl, U, V, W, and Zn, including data that have not been previously reported on Be, Hf, In, Li, Mo, Nb, Sn, Ta, Th, Ti and Zr, and the sum of (14) rare earth elements (ƩREE), were studied in a spatially diverse collection of the B. edulis caps, stipes, and whole fruiting bodies using a validated procedure with measurement by quadrupole ICP-MS. Toxic Cd and Pb were in B. edulis at concentrations below limits set by the European Union in regulations for raw cultivated mushrooms, while Ag, As, Hg, Sb, Tl, and U, which are not regulated, were at relatively low or typical levels as is usually found in mushrooms from an unpolluted area. The elements Be, Bi, Ga, Ge, Hf, In, Nb, Ta, Th, and W, and also ƩREEs, were found at relatively low concentrations in B. edulis, i.e., with levels from below 0.1 to below 0.01 mg kg-1 dw, and for Ʃ14 REEs, the median was 0.31 mg kg-1 dw. The composite samples of caps showed Ag, Cd, Cu, Cs, Ga, Ge, Hg, Mo, Ni, Rb, Sb, Ti, and Zn at higher concentrations than stipes, while Ba, Co, Hf, Sr, Tl, and Zr were found at higher concentrations in stipes than caps (p < 0.05). Mushrooms were characterized by a low coefficient of variation (CV) of below 20%, between sites for concentrations of As, Cu, Ge, Hg, Ni, V, and Zn, while substantial differences (CV > 100%) were found for Ba, Bi, Co, Hf, Zr, and ƩREEs, and an intermediate variation was found for Sr, W, and U. Principal component analysis performed on mushrooms allowed differentiation with respect to 13 collection sites and separation of a consignment that was specifically contaminated, possibly due to a legacy pollution, with significantly higher levels of Ba, Co, Ga, Li, Nb, Ni, Sr, Th, Ti, Y, Zr, and ƩREEs, and another due to possible recent pollution (Pb-gasoline and also Ni); two due to geological contamination because of the Bi, In, Sc, Sb, Sn, Ta, V and W; and one more, the Sudety Mts. site, which was considered as "geogenic/anthropogenic" due to Ag, As, Be, Cd, Cs, Ni, Pb, Rb, Tl, and U.

Radiocaesium Contamination of Mushrooms at High- and Low-Level Chernobyl Exposure Sites and Its Consequences for Public Health

We compare the specific activities of 137Cs and 40K in stipes and caps of three different common mushroom species (Xerocomus badius, Russula ochroleuca and Armillariella mellea) measured at the Czech Chernobyl hot spot in the Opava area (Silesia) and at a low-exposed site at the Beskydy mountains in 2011. The highest values of 137Cs were found in caps of Xerocomus badius and Russula ochroleuca in the Opava area (11.8 and 8.77 kBq/kg, respectively). The source of 137Cs was verified by the measurement of the 134Cs/137Cs ratio. Based on our results, we estimate an effective dose per year due to radiocaesium intake in the two investigated areas for Xerocomus badius, one of the most popular edible mushrooms in the Czech Republic. In 2011, the effective dose reached the maximum value of 0.102 mSv in the Opava area and 0.004 mSv at the low-exposed site at the Beskydy mountains. Therefore, it does not represent a significant risk for public health.

Natural radioactivity and total K content in wild-growing or cultivated edible mushrooms and soils from Galicia (NW, Spain)

The radioactive isotope, ⁴⁰K, of naturally occurring potassium (0.012%) is present in the Earth's crust in a low percentage of all potassium, leading to its presence in almost all foodstuffs. The impact of ⁴⁰K activity concentrations was assessed in wild and cultivated edible mushrooms and in growing substrates. Samples were analysed by gamma spectroscopy. In the wild mushroom species, the average activity concentration of ⁴⁰K was 1291 Bq kg^-1 dry weight (dw), approximately 140 Bq kg^-1 fresh weight (fw), with a range of average values per species from 748 in Lactarius deliciosus to 1848 Bq kg^-1 dw in Tricholoma portentosum. The cultivated species presented an average value of 1086 Bq kg^-1 dw; and the soils, compost of cultivation and wood of substrate are 876, 510 and 59.4 Bq kg^-1 dw, respectively. The total K content reached a maximum of 59,935 mg kg^-1 dw in T. portentosum. The transfer factors (TF > 1) suggested that mushrooms preferentially bioconcentrated ⁴⁰K. Cantharellus cibarius, Craterellus tubaeformis, Hydnum repandum and T. portentosum by most TF could be considered as bioindicators of ⁴⁰K. Taking into account that the annual radiation dose of ⁴⁰K due to the average consumption of mushrooms analysed (0.15 μSv/year) is very low, it can be concluded that the consumption of these mushrooms does not represent a toxicological risk for human health. Finally, according to the total K content, from the nutritional point of view, these mushrooms could be considered as a potential source of potassium for the human diet.

210Po and 210Pb in King Bolete (Boletus edulis) and Related Mushroom Species: Estimated Effective Radiation Dose and Geospatial Distribution in Central and Eastern Europe

²¹⁰Po and ²¹⁰Pb occur naturally and are the most radiotoxic isotopes of the uranium (U) decay chain. Samples of Boletus edulis and related mushroom species, including B. pinophilus, B. reticulatus, B. luridus and B. impolitus, collected from Poland and Belarus were investigated for the activity concentrations of these isotopes and also for their potential health risk through adult human consumption. The results showed that spatially, the occurrence of ²¹⁰Po and ²¹⁰Po was heterogeneous, with activities varying from 0.91 to 4.47 Bq∙kg⁻¹ dry biomass and from 0.82 to 5.82 Bq∙kg⁻¹ db, respectively. Caps and stipes of the fruiting bodies showed similar levels of contamination. Consumption of boletes foraged in Poland could result in exposure to a combined radiation dose of 10 µSv∙kg⁻¹ db from both isotopes. This dose is not significant compared to the total annual effective radiation dose of ²¹⁰Po and ²¹⁰Pb (54–471 µSv∙kg⁻¹) from all sources, suggesting that these mushrooms are comparatively safe for human consumption.

The use of Li2O fortified growing compost to enhance lithiation in white Agaricus bisporus mushrooms: Li uptake and co-accumulation of other trace elements

In an attempt to enrich the fruiting bodies with Lithium (Li), this study cultivated mushrooms using growing sets that were fortified with Li2O at 1.0, 5.0, 10, 50, 100 and 500 mg·kg−1 dw. Compost fortification up to 100 mg·kg−1 dw induced a dose-dependent increase in Li accumulation with resulting median mushroom concentrations of 2.0, 8.6, 16, 29 and 38 mg·kg−1 dw, respectively, relative to the unfortified control at 0.087 mg·kg−1 dw. The dose dependency appears to level off as Li2O addition approaches 100 mg·kg−1, suggesting that there is a limit to the ability of the species to accumulate/tolerate Li. Mushrooms did not grow at the 500 mg·kg−1 dw fortification level. At the highest viable level of fortification (100 mg·kg−1 dw), the fruiting bodies were around 440-fold richer in Li content than the control mushrooms. Additionally, the fortification at all levels up to 100 mg·kg−1 dw showed very low, if any, effect on the co-accumulation of the other, studied trace mineral constituents, with concentrations occurring at the lower range of those reported for commercial A. bisporus mushrooms.

Assessment and Valorization of Non-Wood Forest Products in Europe: A Quantitative Literature Review

This article presents a quantitative review of non-wood forest products (NWFPs) at the regional scale in Europe. A text mining approach was applied to titles, abstracts, and keywords extracted from articles in the Scopus database. Different investigations, such as concept mapping and specificity analyses of textual corpus, were performed. Our search yielded a massive number of NWFP-related papers. Specifically, research was distributed in different countries, being more prevalent in the Mediterranean and Scandinavian contexts. Several NWFPs were analyzed, with mushrooms, resin, cork, and other forest fruit being the most common ones. Local socioeconomic improvement was one of the major aspects investigated in scientific literature. The proposed methodology applies specific scripts that can be updated, and the output of the present research can be compared with that of the future works. For instance, interest trends of products and methods can be investigated, and gap analyses performed. Finally, the potential implications of this review for researchers and stakeholders are discussed.