Nuclear analytical techniques used to study the trace element content of Centaurium erythraea Rafn, a medicinal plant species from sites with different pollution loads in Lower Silesia (SW Poland).

Centaurium erythraea (Gentianaceae) is a medicinal plant species with therapeutic potential officially listed in the pharmacopoeias of many European, Asian and American countries. It has had many uses in natural medicine since ancient times and it is collected mostly from wild populations. The aim of this study is to investigate the trace element composition of C. erythraea using instrumental neutron activation analysis (INAA). The results of the performed investigations show that INAA has proved to be an efficient analytical technique for the determination of trace elements in medicinal plants. The studied plant contains elements important to the human diet and metabolism that are needed for growth, development and the prevention and curing of disease. A comparison with the reference levels of elements for plants shows that the concentrations of most elements in C. erythraea collected from all types of sites exceed those regarded as the reference. Compared to the values of the elements in C. erythraea from rural areas (LP), the concentrations of most of the investigated elements in C. erythraea collected from the lignite basin, urban areas and in the vicinity of the A4 highway (MP) were significantly higher. The results obtained can be used for control and monitoring in the production of pharmaceuticals based on natural medical plants.

Bio-zeolite use for metal removal from copper-containing synthetic effluents.

The adsorption capacity of biologically modified zeolite with respect to copper-containing effluents (Cu(II)-Fe(III), Cu(II)-Fe(III)-Ni(II), Cu(II)-Fe(II)-Zn(II), and Cu(II)-Fe(II)-Ni(II)-Zn(II)) has been investigated in order to apply it for industrial effluents treatment. Obtained bio-zeolite was characterized using neutron activation analysis, confocal laser scanning microscopy, and scanning electron microscopy. The efficiency of metal ions removal was determined as a function of pH, copper concentration, time, and temperature. The metal sorption in analyzed systems showed to be pH-dependent. The equilibrium adsorption data were interpreted using Freundlich and Langmuir isotherms and the adsorption mechanism was investigated by kinetic studies. The sorption of Cu(II) and Zn(II) fitted well pseudo-first and pseudo-second-order models, while Ni(II) sorption was better described by the Elovich model. The thermodynamic parameters, ∆G°, ∆H°, and ∆S were evaluated to understand the nature of the sorption process. Obtained results show that bio-zeolite is of interest for heavy metal ions removal from industrial effluents. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40201-021-00694-x.

Multivariate assessment of atmospheric deposition studies in Bulgaria based on moss biomonitors: trends between the 2005/2006 and 2015/2016 surveys.

This study aims to investigate the changes in atmospheric deposition trends in Bulgaria, studied using the moss biomonitoring technique since 1995. For the first time, a paired (site-wise) comparison was performed after a critical review of the sampling networks and adjusting for location, the distance between the sampling points, and moss species. Data from the 2005/2006 and 2015/2016 moss surveys were chosen as instrumental neutron activation analysis was employed in both to determine the content of 34 elements (Al, As, Ba, Br, Са, Ce, Cl, Со, Cr, Cs, Fe, Hf, I, K, La, Mn, Na, Nd, Ni, Rb, Sb, Sc, Se, Sr, Ta, Tb, Th, Ti, Tm, U, V, W, Yb, Zn). In addition, Cd, Cu, and Pb were determined using complementary analytical methods: inductively coupled plasma atomic emission spectroscopy in 2015/2016 and atomic absorption spectroscopy in 2005/2006. For the subset of 57 routinely sampled locations in Bulgaria, hierarchical clustering on principal components and multiple factor analysis (MFA) were applied to assess the spatial trends in the 10 years elapsed between the surveys, as well as to characterise the origin of the determined elements. Elevation and distance between the sampling points were used as additional variables in the multiple factor analysis plane to ascertain their effect on the overall variance in the datasets. Distribution maps were constructed to illustrate the deposition patterns for the pollutant Pb. The results were consistent with decreased industrial output in the country, increased coal combustion and transport pollution, and construction of roads.

Chlorophyll Content in Two Medicinal Plant Species Following Nano-TiO2 Exposure.

Chlorophyll content in leaves is a convenient indicator of the physiological state of the plant following exposure to a stressor. In the present study, a pot experiment was carried out using two medicinal plant species - peppermint (Mentha X piperita L.) and common sage (Salvia officinalis L.) to determine the link between the chlorophyll content in the plant leaves and the exposure of the plants to nano-TiO2 either through the leaves (in suspension) or through the root system (in soil). Following the exposure, the shoots were analysed for the contents of Ti, Al, Ca, K, Mg, Mn, Na and chlorophyll. Significant decrease in chlorophyll content was observed in all but one of the nano-TiO2 treatments, the differences in the determined element content were mostly species-dependent: Ti exposure was found to be related to the decrease in the chlorophyll and Mn content in both species as well as to the decrease in Mg content in common sage.

Quaternized pine sawdust in the treatment of mining wastewater.

Mining wastewater was treated using quaternized pine sawdust (QPSD) anion exchanger. The wastewater contained heavy metals (e.g. Sb, As, Co, Cr, Ni, V, U), NO3(-), among others, and a high concentration of SO4(2-). A series of column cycles imitating a real treatment process was conducted (three sorption/desorption cycles, a maintenance cycle with HCl and two sorption/desorption cycles). The effects of contact time and temperature (5°C and 23°C) were studied to assess the applicability of QPSD in the treatment of cold mining effluents. At 5°C, 85% of nickel was removed but the sorption was slower than at 23°C (initial Ni concentration was about 39 µg/l). Nickel was also removed in column efficiently (85-100% reduction). Treatment with HCl during the maintenance cycles did not hinder nickel sorption. Nickel was desorbed with both NaCl and HCl. Contrary to expectations, nitrate was not sorbed. QPSD showed selectivity towards nickel. However, uptake of uranium and cobalt was detected in column. Neutron activation analysis was used to detect metals sorbed onto the QPSD, and uptake of several metals was confirmed.