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EN
Water environments are noted as being some of the most exposed to the infl uence of toxic nanoparticles (NPs). Therefore, there is a growing need for the investigation of the accumulation and toxicity of NPs to aquatic organisms. In our studies neutron activation followed by gamma spectrometry and liquid scintillation counting were used for studying the accumulation of silver nanoparticles (AgNPs) by freshwater larvae of Chironomus and fi sh Danio rerio. The infl uence of exposition time, concentration and the source of nanoparticles on the effi ciency of AgNP accumulation were studied. It was found that AgNPs are effi ciently accumulated by Chironomid larvae for the fi rst 30 hours of exposition; then, the amount of silver nanoparticles decreases. The silver content in larvae increases together with the NP concentration in water. Larvae which have accumulated AgNPs can be a source of nanoparticles for fi sh and certainly higher levels of Ag in the trophic chain. In comparison with water contamination, silver nanoparticles are more effi ciently accumulated if fi sh are fed with AgNP-contaminated food. Finally, it was concluded that the applied study strategy, including neutron activation of nanoparticles, is very useful technique for tracing the uptake and accumulation of NPs in organisms.
EN
The microbial assay for risk assessment (MARA) test was used for acute cesium toxicity evaluation in water solutions. The test contained 11 different microorganisms with a wide spectrum of sensitivity. The resistance of microorganisms to cesium was characterized as follows: microbial toxic concentration (MTC), half maximal inhibitory concentration (IC50), maximal inhibitory concentration (IC100). The sensitivity to cesium was characterized by the lowest observed effect level (LOEL). High levels of sensitivity in the range 3.1–6.3 mM were shown by the following microorganisms: Serratia rubidaea > Pseudomonas aurantiaca, Delftia acidovorans, Citrobacter freundii, Staphylococcus warneri. Lower levels of sensitivity (up to 16 mM) were noted for Comamonas testosteroni, Microbacterium species, Kurthia gibsonii, Pichia anomala, whereas that in the range 24–31 mM for Brevundimonas diminuta > Enterococcus casseliflavus. High resistance to Cs+ was found for E. casseliflavus (MTC 86.9 g/l) > the yeast – P. anomala (MTC 19.3 g/l) > K. gibsoni (MTC 17.4 g/l) > B. diminuta (MTC 13.4 g/l). The phenomenon of resistance of enterococcus and yeast strains was discussed.
EN
As a result of the rapid development of nanotechnology and increasing application of nanoproducts in many areas of everyday life, there is a growing risk of production of nanowastes potentially dangerous for the environment. This makes it necessary to investigate the accumulation and toxicity of nanoparticles (NPs) at different trophic levels. In the studies neutron activation was applied for the investigation of iron (II,III) oxide nanoparticle (Fe3O4-NPs) accumulation by Lepidium sativum and Pisum sativum L. Plants were cultivated on growth medium contaminated with different concentrations (0.01-10 mmolźL-1) of Fe3O4-NPs. For the identification of the presence of Fe3O4-NPs in plant tissues gamma spectrometry following iron oxide (II,III) nanoparticles irradiation was applied. Both plant species were found to accumulate iron (II,III) oxide nanoparticles. The highest content of NPs was found in plant roots, reaching 40 g/kg for Pisum sativum L. More than 90% of accumulated NPs were found in roots. Accumulation of Fe3O4-NPs was found to depend on the concentration of nanostructures in the growth medium. The transfer factor for Lepidium sativum roots and shoots and Pisum sativum L. shoots decreased with increasing NP concentration in the medium; for Pisum sativum L. roots the tendency was reversed. Neutron activation of nanoparticles was shown to be a powerful tool for tracing the environmental fate of NPs and their uptake and accumulation in organisms.
EN
Experiments were carried out to determine uptake and distribution of 137Cs, and total isotopes of Cs and K in plants of heather (Calluna vulgaris) growing at two levels of CsCl: 0.03 and 0.3 mM. Levels of Cs and K were determined in soil and in parts of plants: roots, stem, leaves and flowers. Also calculated were: (i) transfer factor of Cs and K from soil to parts of plant and (ii) discrimination of K by Cs during the transport of Cs from roots to aboveground parts of plants, expressed as K/Cs discrimination factor. The results confirmed that heather plants are hyper-accumulators of cesium, because the accumulation of Cs in shoot was much greater than in roots. The K level in heather did not change at Cs concentrations as high as 8-fold Cs level in this plant. Heather plants seem to be relatively resistant to cesium toxicity at 0.3 mM of CsCl; the effect of exposure to CsCl at this concentration was exerted only on roots, without affecting leaves and flowers. These results supply new information on the interactions between Cs and K nutrition in plants; they also point to a possible role of heather in redistribution of the radiocesium pollution in the forest ecosystem.
EN
A model species of saprophytic fungus, king oyster mushroom (Pleurotus eryngii), was cultivated on barley substrate supplied with [Pt(NH3)4](NO3)2, under well defined conditions. The samples of the collected fruiting bodies were digested and analyzed for total platinum content by means of ICP-MS. The results proved that platinum is not accumulated in the fruitbodies of Pleurotus eryngii for a wide range of Pt concentrations in the culture substrate (100 1000 ppb Pt in 50 ml of water solution added to ca. 450 g of hydrated barley seeds per container). Observable levels of Pt were only found in the fruitbodies obtained from the medium contaminated with 10000 ppb (10 ppm) platinum solution. This demonstrates significant difference in the effectiveness of platinum extraction in fungi and plants, which are capable to accumulate platinum even when supplied at lower concentration (<500 ppb). It also shows different physiological pathways of platinum and other elements which are easily accumulated in the fruitbodies of the same species.
EN
The ability of hydroponically cultivated Indian mustard plants (Sinapis alba L.) to accumulate platinum was investigated. The Pt-bioaccumulation in leaves, stem and shoots of plants growing for 2 and 4 weeks at Pt-concentration of 50 and 500 ěg/L was compared. The relation between dry and fresh weight was also estimated. Adsorptive stripping voltammetry (AdSV) and mass spectrometry with inductively coupled plasma (ICP-MS) were applied for determination of Pt. Increasing Pt-concentration from 50 to 500 ěg/L in the medium causes: (1) reduction of the root tissue hydration level at unchanged modification in aboveground parts of the plants and (2) decrease of the Pt transfer factor (TF) for roots and increase for leaves and stem. Duration of the culture influenced on Pt-accumulation in roots and in aboveground organs of mustard plants. Transfer factor for Pt between 560 and 1600 makes Indian mustard plants one at Pt-hyperaccumulators. Distribution of Pt-bioaccumulation in the plant organs may be useful for biomonitoring of platinum in the environment.
7
Content available Editorial
EN
In order to explain influence of common cations (K+, Na+ and Ca2+) on uptake and transport of caesium in macromycetes, a culture of a model mushroom species, king oyster mushroom (Pleurotus eryngii) was set up. Fructification in a growing chamber with stabilised temperature (18°C) and humidity (80%) was preceded by mycelial colonization of the sterilized barley seed medium packed into autoclavable plastic containers. Aliquots of test solutions, containing 0.1 mM caesium chloride carrier traced with 137CsCl and the selected ions, were dosed into the interphase between the container wall and the spawn block. This allowed to study influence of the added ions on the uptake of caesium in a way unaffected by the used growing medium, e.g. soil, as it was in the previous studies. The experiments demonstrated that the major amount of radiocaesium was biologically bound and accumulated in the fruitbodies to a higher extent (56 69%) than in the mycelium. Addition of 10 mM Na+ decreased the transfer factor for caesium (cap/soil) while addition of Ca2+ caused an increase of this value. The effect of potassium addition depended on its concentration in the solution. Also the Cs/K ratio in caps was significantly influenced by addition of 10 and 100 mM Na+. However, the Cs/K ratio in stipes was affected by Ca2+. Discrimination factors, calculated from specific activities (137Cs/40K cap d.w.)/(137Cs/40K stipe d.w.), were also changed after addition of the studied cations. Since the activities of caesium measured in the fruitbodies of single fungal species strongly depend on the content of co-supplied ions, further proofs should be achieved before using mushrooms as bioindicators of the soil caesium contamination.
EN
Activities of caesium in the mushrooms collected at different localities in Poland and Slovakia have been compared. Discrimination factor, defined as [(Bq.kg 1 137Cs in caps)/(Bq.kg 1 40K in caps)]/[(Bq.kg 1 137Cs in stipes)/ (Bq.kg 1 40K in stipes)], was used to explain mechanisms of uptake and transport of radiocaesium in fungi. The collected specimens were divided into caps and stipes. Activities of 137Cs and 40K were measured using a multichannel gamma spectrophotometer with HPGe(Li) detector. The highest accumulation of 137Cs was found in the samples of Xerocomus badius, Suillus luteus and Tricholoma equestre (2.7, 1.9 and 1.2 kBq.kg 1, respectively). T. equestre and S. luteus proved to hyperaccumulate caesium since 137Cs levels in the caps were two orders of magnitude higher than in the soil while only one order higher in the case of X. badius. Transport of 137Cs from stipe to cap in fruitbody is directly related to K concentration with lack of similar dependence in the case of transport from soil to cap. There is no dependence between activity of 137Cs in the analyzed fruitbodies and its activity in the soil, which makes mushrooms controversial bioindicators
EN
Croton (Codiaeum variegatum) belongs to the salinity-resistant plants. This paper presents some experimental data in order to assess usefulness of croton plants for phytoremediation of caesium-contaminated soils. The plants were grown in a greenhouse, in the soil contaminated with 0.03, 0.3, 1, 3, 5 and 10 mM CsCl solution enriched with 137Cs as a radiotracer. The croton plant demonstrated high resistance to increasing CsCl salinity of the soil. This conclusion was based on the observation that the above-ground organ fresh-to-dry weight ratio was constant. However, this value was lower for the roots. The young-to-old leaf dry weight ratio was decreasing while the concentration of CsCl in the soil was increasing. The increase in soil CsCl concentration was associated with the decrease in photosynthesis as well as a rise in the intra-tissue concentration of CO2 and increase of the CO2 stomatal conductance. Photosynthetic water utilization efficiency was constant in the range of 0.03-1 mM CsCl and it was only lower with higher CsCl concentration. This situation gives an evidence that croton plant is highly resistant to the soil CsCl salinity. The 137Cs radiotracer experiment showed the maximal accumulation of caesium with 0.3 mM CsCl, a lower one with 0.03 mM, and poor accumulation with 3 and 5 mM CsCl solutions. The transfer factor value for 137Cs (plant-to-soil) was about 10, which proved a high ability of croton plants to accumulate caesium to a high extent. However, the highest accumulation took place in the roots. The intensive phytoextraction of caesium from the soil may indicate its potential capacity for bioremediation. The reported observation warrants further studies.
EN
The plants of three species (Zea mays L., Panicum miliaceum L. and Panicum maximum Jacq.) were grown on the soil contaminated with 0.3 mM CsCl solution traced with 137Cs, in the greenhouse. For all the species, the fresh-to-dry weight ratio was equal in the caesium-treated plants and in the control group after 3 weeks of culture. The shoot-to-root fresh weight and dry weight ratios were decreased in maize, unchanged in Panicum miliaceum and increased in Panicum maximum, comparing to the control without caesium treatment. The shoot/soil and also root/soil transfer factors (TF) for 137Cs (measured by means of NaI gamma spectrometer) were always the highest in maize, then lower in Panicum miliaceum and the lowest in Panicum maximum. All the plants seem to be hyperaccumulators of caesium. The root/soil TF was especially high in maize, i.e. 55 (kBq kg 1 biomass)/(kBq kg 1 soil). The shoot/root concentration factor (CF) for 137Cs was the lowest in maize, higher in Panicum miliaceum and the highest in Panicum maximum. The hyperaccumulation of 137Cs in the whole plant was the highest in maize, lower in Panicum miliaceum and the lowest in Panicum maximum. The proved ability of the investigated plants for phytoextraction of the soil caesium points to the possibility to utilise these plants in the soil bioremediation. From this point of view, Panicum maximum seems to be the most useful plant because it accumulates caesium mainly in the shoot, and maize would be the least useful species since it has the highest accumulation in the root.
EN
The ability of platinum uptake by hydroponically cultivated plants - Indian mustard (Sinapis alba L.) and Anawa maize (Zea mays L.) - was investigated. The efficiency of the transport of platinum compounds from the roots to above ground organs was estimated. For platinum determination in plant samples, digested in closed system with microwave energy, very sensitive analytical methods were applied - adsorptive stripping voltammetry (AdSV) and mass spectrometry with inductively coupled plasma (ICP-MS). For validation of the obtained results the recovery of platinum was examined. The accumulation factors (AF) of platinum: more then 800 and 400 for roots of Indian mustard and Anawa maize, respectively and about 90 and 30 for above ground organs of both species were found.
13
Content available Foreword
EN
A simple model of Pleurotus eryngii mushroom culture, grown under stringent laboratory conditions, was developed to watch ecophysiological pathways of xenobiotics in saprophytic fungi. The investigated substances may be added in different stages of biological cycle of the fungus. It is emphasized that to obtain the fruitbodies, all the physiological needs of the species have to be fulfilled, i.e.: nutritional requirements, optimal temperature (according to the biological cycle), humidity, aeration (oxygen and CO2), absence or presence of the light in each reproduction phase, as well as the control of infections and plagues through all the production stages. The described model serves for investigation of radionuclide and heavy metal uptake and transfer in fungi. Double or some multiple fructification from the same substrate is possible giving a possibility to investigate bioremediation by mycoextraction.
EN
Samples of five species of wild edible mushrooms, growing in the vicinity of Warsaw, were analyzed in order to determine discrimination factors (DF) for 137Cs and 40K in their caps and stipes. The obtained DF values range from 0.80 to 2.87, and seem to be characteristic of each species. A brief discussion of the observed phenomenon is presented.
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