| Notes | 'Annotations(1/12/2024, 1:24:03 PM)\n“Most radionuclides, whether anthropogenic or naturally occurring, are also heavy metals, and can be bioaccumulated by mushrooms” (Guillén and Baeza, 2014, p. 15)“The analysis of the radioactive content of mushrooms has mainly focused on radiocaesium. There are essentially two reasons for this. One is that it is a long-lived anthropogenic radionuclide (T½ = 30.2 y) that has been released into the environment by atmospheric nuclear weapons tests and various accidents involving nuclear materials (UNSCEAR, 2000). The second is that it is a chemical analogue of potassium” (Guillén and Baeza, 2014, p. 15)“Xerocomus badius,” (Guillén and Baeza, 2014, p. 17)“Cortinarius” (Guillén and Baeza, 2014, p. 17)“Leucopaxillus giganteus” (Guillén and Baeza, 2014, p. 17)“Armillaria gallica” (Guillén and Baeza, 2014, p. 17)“In the case of X. badius and Boletus erythropus, some pigments present in the cap, derivatives of the pulvinic acid, badione A1, and norbadione A2, were found to efficiently bind potassium and caesium” (Guillén and Baeza, 2014, p. 18)“The habitat of the mycelium, i.e., the substrate from which the mushroom takes up nutrients together with radionuclides, has a major influence on its radiocaesium content. Cultivated mushrooms, usually grown on wood, sawdust, etc., present lower 137Cs levels than wild mushrooms, due to the lower radiocaesium contents of these substrates than those of soils (” (Guillén and Baeza, 2014, p. 18)“These variations reflected differences in the depth of the location of their mycelium in the soil. After radiocaesium is deposited on the surface soil, it begins to migrate downwards at speeds dependent on the soil’s characteristics (clay content, organic matter, pH, etc.) (IAEA, 2006). Those species whose mycelium is located in the surface layer of soil may show decreasing 137Cs content with time, while those with deeper mycelium may show an increasing trend” (Guillén and Baeza, 2014, p. 18)“The mushroom’s nutritional mechanism also plays an important role in the accumulation of radiocaesium. Mycorrhizal fungi, symbiotic with tree roots, present higher 137Cs contents than saprophytes (living on organic matter) or parasites” (Guillén and Baeza, 2014, p. 18)“The higher accumulation in mycorrhizal mushrooms is attributed to the fact that the host plant can discriminate caesium from potassium, with the fungus thus acting as a filter for the host plant (Guillitte et al., 1994; Kammerer et al., 1994). This was confirmed to some extent by radiotracer laboratory experiments, in which radiocaesium transfer to pine plantlets was reduced by symbiosis with mycorrhizal fungi (” (Guillén and Baeza, 2014, p. 18)“For ripe mushrooms, it is accumulated preferentially in the gills, followed by cap and stipe” (Guillén and Baeza, 2014, p. 18)“The stage of maturity also affects the total radiocaesium content which is maximal at ripeness and decreases with further aging, probably due to nutrient translocation back to the mycelium (” (Guillén and Baeza, 2014, p. 18)“Mushrooms accumulate 90Sr to a lesser degree than 137Cs, with the 90Sr/137Cs ratio being less than unity (range 0.001–0.70)” (Guillén and Baeza, 2014, p. 18)“Compared to plants, the elemental composition of mushrooms is characterized by high Rb and Cs contents and low Ca and Sr contents” (Guillén and Baeza, 2014, p. 18)(Guillén and Baeza, 2014, p. 18) Seems like mushrooms are the best radioaccumulators during their first cycle of maturation? With highest ripe particle concentration in the Cap + Gills, followed by some distribution back into the mycelium.“Although caesium is a chemical analogue of potassium, no correlation between 137Cs and 40K has been found, suggesting different uptake mechanisms for these two elements” (Guillén and Baeza, 2014, p. 19)“The uptake by mushrooms of uranium and thorium is lower than that of 40K, since they are not essential to the development of fungus” (Guillén and Baeza, 2014, p. 19)“The presence in the environment of naturally occurring radionuclides is not usually due to accidents involving nuclear materials” (Guillén and Baeza, 2014, p. 19)“bioaccumulation by mushrooms has been used to identify depleted uranium (DU) in areas of former Yugoslavia, where this kind of ammunition was used” (Guillén and Baeza, 2014, p. 19)“Some cooking procedures can significantly reduce the radionuclide content (Table 6). That washing reduces the radiocaesium content may be attributed to the partial removal of radiocaesium-binding pigments present in the cap” (Guillén and Baeza, 2014, p. 21)“The addition of 2% acetic acid to dried mushrooms (Xerocomus badius, S. luteus, and Lepista saeve) exponentially reduced their 137Cs content over a 6–48 h time span” (Guillén and Baeza, 2014, p. 21)“Drying is an ancient method of mushroom preservation, but it is the only one that increases the radionuclide content due to the loss of water” (Guillén and Baeza, 2014, p. 21)“Parboil, salt, then soak 90” (Guillén and Baeza, 2014, p. 22)\n\n - AlexanderSE'
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