Mycoextraction of radiolabeled cesium and strontium by Pleurotus eryngii mycelia in the presence of alumina nanoparticles: Sorption and accumulation studies

Widespread use of products based on nanomaterials results in the release of nanoparticles into the environment. Nanoparticles can be taken up by organisms, but they can also coexist with other substances such as radionuclides, thus affecting their uptake or toxicity. In contrast, the sorption capacity of nanoparticles is exploited in water purification. The aim of the study was to investigate: (i) bioaccumulation of cesium and strontium by Pleurotus eryngii mycelia in the presence of alumina nanoparticles (Al₂O₃ NPs); and (ii) sorption of radionuclides on the surface of nanoparticles. For the experiments, living and dried mycelia were used to permit distinguishing between active uptake and passive sorption of the NPs by P. eryngii. The results are discussed from the perspective of the use of P. eryngii in the mycoextraction of radionuclides. The sorption capacity of Al₂O₃ NPs and the accumulation by P. eryngii mycelia differ for the applied radioisotopes. The efficiency of Cs and Sr sorption by alumina nanoparticles is 20% and 40%, respectively. Mycelia of P. eryngii have the ability to accumulate 30% of both radioisotopes from the medium. More than 60% of strontium can be removed accumulated from water by P. eryngii mycelia in coexistence with Al₂O₃ NPs, while the efficiency of cesium removal accumulation is negligible. It was found that alumina nanoparticles do not enhance uptake of radionuclides by P. eryngii mycelia; mycoextraction of radionuclides by mycelia and sorption by Al₂O₃ NPs are concurrent processes. There was no difference between live or dried mycelia uptake. - Highlights: • Pleurotus eryngii mycelia accumulate Cs and Sr in the presence of Al₂O₃ nanoparticles. • Al₂O₃ nanoparticles remove about 40% of Sr from the water. • Combination of mycelia and nanoparticles remove up to 60% of Sr from the water. • Dried mycelia filled with nanoparticles can be used for mycoextraction of Sr.