The Phytoremediation Potential and Physiological Adaptive Response of Tamarix tetrandra Pall. Ex M. Bieb. during the Restoration of Chronosequence Fly Ash Deposits.

The challenging process of identifying and selecting plant species suited to the phytoremediation of fly ash (FA) dumps involves studying their functional properties and physiological response to a deficit of essential elements and toxicity from heavy metal(loid)-induced oxidative stress. We hypothesised that Tamarix tetrandra has high potential to be used for the phytoremediation of FA deposit sites thanks to its secretion strategy and antioxidative system. In this study, this hypothesis was examined by determining the bioconcentration and translocation factors for As, B, Cr, Cu, Mn, Ni, Se and Zn at the FA disposal lagoons at the 'Nikola Tesla A' thermal power plant in Obrenovac, Serbia, three (lagoon L1) and eleven (lagoon L2) years after the phytoremediation process had begun, and by measuring parameters of photosynthetic efficiency and chlorophyll concentration, non-enzymatic antioxidant defence (carotenoids, anthocyanins and phenolics), oxidative stress (concentration of malondialdehyde-MDA) and total antioxidant capacity to neutralise DPPH free radical activity. Tamarisk not only showed the ability to phytostabilise As, Cr and Ni and to accumulate low-availability Mn, Zn and Cu, but also the potential to maintain the structural and functional integrity of cell membranes and stable vitality at L1 under multiple stress conditions due to the high synthesis of phenols and tolerance to increased salinity. However, toxic concentrations of B and Se in leaves induced oxidative stress in tamarisk at L2 (reflected in higher MDA content and lower vitality) and also decreased the synthesis of chlorophyll, carotenoids, anthocyanins and total antioxidant activity. In addition, the prooxidative behaviour of phenols in the presence of spin-stabilising metals from FA could also have resulted in their weaker antioxidant protection at L2. These findings indicate that the choice of tamarisk was justified, but only at the beginning of the phytoremediation process because its presence contributed to an improvement in the harsh conditions at FA deposit sites and the creation of more favourable conditions for new plant species. This knowledge can be of great importance when planning sustainable ash deposit site management worldwide.

Chemical Fractionation, Environmental, and Human Health Risk Assessment of Potentially Toxic Elements in Soil of Industrialised Urban Areas in Serbia.

The primary focus of this research was the chemical fractionation of potentially toxic elements (PTEs) and their presence in several industrialised cities in Serbia. Furthermore, their origin, contamination levels, and environmental and human health risks were assessed. The results indicated that the examined soils were characterised by slightly higher Cu, Ni, Pb, and Zn levels than those set by European and national regulations. These elevated Cu, Pb, and Zn concentrations were caused by intensive traffic and proximity to industry, whereas the higher Ni levels were a result of the specific geological substrate of the soil in the study area. The environmental risk was found to be low and there was no enrichment/contamination of the soil with these elements, except in the case of Pb, for which moderate to significant enrichment was found. Lead also poses a potential non-carcinogenic risk to children through ingestion and requires special attention due to the fact that a significant proportion of this element was present in the tested soil samples in a potentially available form. Analysis of the health risks showed that children are more at risk than adults from contaminants and that ingestion is the riskiest exposure route. The carcinogenic risk was within the acceptable limits.

Evaluation of Salix alba, Juglans regia and Populus nigra as biomonitors of PTEs in the riparian soils of the Sava River.

A large number of human activities result in the release of potentially toxic elements (PTEs) into the environment, which could lead to the degradation of riparian areas. This study aimed to evaluate the potential of Salix alba, Juglans regia and Populus nigra for the biomonitoring of PTEs in the riparian soils of the Sava River. Levels of seven PTEs (As, Cd, Cr, Cu, Ni, Pb and Zn) were measured in the soils, roots and leaves of plants at selected sampling sites and evaluated according to bioaccumulation and translocation factors. The obtained results showed that in riparian soils, As, Cr, Cu, Ni and Zn were at levels considered to be critical for plants. The levels of As, Cd, Cr, Ni and Zn measured in roots of Salix alba and As, Cr, Ni and Zn in its leaves were toxic for plant tissue. Toxic levels of Cr were also measured in the roots of Juglans regia and As in its leaves, as well as As and Cr in the roots of Populus nigra, and Zn in its leaves. Bioconcentration and translocation factors showed that S. alba and P. nigra have potential for the phytoextraction of Zn and Cd, while J. regia has potential for the phytoextraction of As. In terms of phytostabilization potential, S. alba proved to be good for the phytostabilization of Cd and Cu, and J. regia for the phytostabilization of Cr, As, Ni and Pb, while P. nigra showed potential for the phytostabilization of Cr, Ni, Pb and Cu.

The potential of elm trees (Ulmus glabra Huds.) for the phytostabilisation of potentially toxic elements in the riparian zone of the Sava River.

The use of trees to immobilise potentially toxic elements (PTEs) is a low-cost and effective method of soil remediation. Thus, the objective of this study was to assess the content of total and bioavailable As, Cd, Cr, Cu, Ni, Pb and Zn in soil samples, as well as their levels in the roots and leaves of elm (Ulmus glabra Huds.) in order to evaluate its potential for the phytostabilisation of PTEs in the riparian zone of the Sava River. Analysis of soils showed that the availability of PTEs ranged from low to medium, while the pollution load index (PLI) and potential ecological risk index (RI) showed that the examined soil fell into the category of uncontaminated to moderately contaminated, as well as into the category of low risk of PTEs contamination. However, the levels of Cr, Cu and Ni in soils were above the critical range for plants. The content of As and Cr measured in roots and leaves was in the toxic range for plants, while the content of Cd and Ni was elevated but not in the toxic range. Bioaccumulation (BCF) and translocation (TF) factors indicated that U. glabra is suitable for the phytostabilisation of As, Cu, Cr, Ni and Pb. Additionally, this species displayed the ability to transport most of the acquired Cu and Zn to the leaves. Correlation analysis showed that PTE content in U. glabra roots was significantly positively correlated to their respective levels in soil (total and DTPA-extractable), except for Cu, indicating that PTE levels in soil strongly influence those in plants. This research into a successful phytoremediating species provides new possibilities when selecting PTE-tolerant native trees in riparian zones of large regional rivers such as the Sava.

Traditional wound-healing plants used in the Balkan region (Southeast Europe).

ETHNOPHARMACOLOGICAL RELEVANCE: The geographical and ecological specificity of the Balkan Peninsula has resulted in the development of a distinct diversity of medicinal plants. In the traditional culture of the Balkan peoples, plants have medicinal, economic and anthropological/cultural importance, which is reflected in the sound knowledge of their diversity and use. This study analyses the traditional use of medicinal plants in the treatment of wounds and the pharmacological characteristics of the most frequently used species. MATERIALS AND METHODS: A detailed analysis of the literature related to ethnobhe uses of medicinal plants in the Balkan region was carried out. Twenty-five studies were analysed and those plants used for the treatment of wounds were singled out. RESULT: An ethnobotanical analysis showed that 128 plant species (105 wild, 22 cultivated and 1 wild/cultivated) are used in the treatment of wounds. Their application is external, in the form of infusions, decoctions, tinctures, syrups, oils, ointments, and balms, or direct to the skin. Among those plants recorded, the most commonly used are Plantago major, Hypericum perforatum, Plantago lanceolata, Achillea millefolium, Calendula officinalis, Sambucus nigra, Tussilago farfara and Prunus domestica. The study showed that the traditional use of plants in wound healing is confirmed by in vitro and/or in vivo studies for P. major and P. lanceolata (3 laboratory studies for P. major and 2 for P. lanceolata), H. perforatum (5 laboratory studies and 3 clinical trials), A. millefolium (3 laboratory studies and one clinical trial), C. officinalis (6 laboratory studies and 1 clinical trial), S. nigra (3 laboratory studies) and T. farfara (one laboratory study). CONCLUSION: The beneficial effects of using medicinal plants from the Balkan region to heal wounds according to traditional practices have been proven in many scientific studies. However, information on the quantitative benefits to human health of using herbal medicines to heal wounds is still scarce or fragmented, hindering a proper evaluation. Therefore, further studies should be aimed at isolating and identifying specific active substances from plant extracts, which could also reveal compounds with more valuable therapeutic properties. Furthermore, additional reliable clinical trials are needed to confirm those experiences encountered when using traditional medicines. A combination of traditional and modern knowledge could result in new wound-healing drugs with a significant reduction in unwanted side effects.