Standardization process by NAA method for phytopharmaceutical industry

The ancient therapeutic remedies for modern needs are represented by medicinal crop plants, the raw material for phytopharmaceutical forms. Medicinal plants are generally viewed only in terms of beneficial effects without considering the potentially toxic side [1]. In this context in the present study elemental composition for seven representative medicinal crop plants as: coriander, dill, Echinacea, lavender, chamomile, mint and plantain, cultivated in unpolluted areas in Romania, were analyzed. Among many analytical methods used for determination of plant elemental content, that generally imply the vegetal matrix disintegration, the Neutronic Activation Analysis (NAA) is classified as primary ratio method [2]. By validating the NAA procedure by statistical evaluation of the nominal error En≤1 (ISO 13528-2015) [3], NAA proved to be an accurate, specific and multielement analysis technique for medicinal plants with the advantage of eliminating the preliminary step of digestion, in this way certain errors being avoided. This method is differentiated as one with high potential to obtain internal plant standards in the phytopharmaceutical industry. These standards can be vegetable matrix, or plant specific, once achieved can be used a long period of time to verify and validate more routinely accessible analytical techniques, which in turn require a digestion stage. A critical assessment provided by the results include the essential nutrients (K, Ca, Mg, Na, Fe, K, Mn, Zn), micro- and trace elements (Co, Cr, Cu, Ni, Se, V), as well as the undesirable, potentially toxic elements (Al, As, Ba, Co, Cr, Ni, Sb) together with rare earth elements. The values are comparable with literature. These plants may provide a useful contribution to food intake with essential macronutrients (K, Ca, Mg) and the concerns regarding the toxicity of metals for a person, are removed. Seemingly the Al (4997 ppm) and Fe (3315 ppm) [4] content in lavender is of some worry. In fact, many studies [5] revealed that some plants species, and lavender among them, exhibit metal bioaccumulation properties and are used for phytoremediation of contaminated soils. This dual implication, beneficial for soil depollution, but critical in transmitting the accumulated metals to humans, is to be considered. Choosing an unpolluted area, in order to cultivate medicinal plants, seems to be an efficient strategy from this point of view. Still, another conclusion is that a rigorous analytical control of the raw materials is advisable for some of the elements (among them aluminium) to avoid risks

A closure study on aerosol extinction in urban air in Hungary

In this study, we present our results from an investigation into the use of visibility data as a viable tool for the survey of long-term variations in air quality. We found that visibility data in general can be used to estimate atmospheric aerosol extinction coefficients, and that PM10 can be successfully estimated from aerosol chemical composition. Our results indicate that PM10 concentrations provide a good basis for the reconstruction of aerosol extinction coefficients. It was also shown that both derived (from visibility) and reconstructed aerosol extinction coefficients were in good accordance with each other, mainly in the case of dry aerosols. Ambient values can be determined if an adequate hygroscopic growth rate for aerosol extinction is considered. We also found that a rather precise estimation of extinction coefficient can be reached if a modified version of the widely used IMPROVE formula is applied

High-energy detector calibration data for k(0)-neutron activation analysis

In k(0)-neutron activation analysis, HPGe detectors have to be calibrated up to about 3.1 MeV, in order to properly determine the Na, Ca and S content of analytes. Commercial radioactive sources cover the energy range only up to 2.2 MeV, but with activation in the reactor, additional high-energy gamma emitter radionuclides (Ga-72, Mn-56, In-116 and Na-24) can be produced. At a prompt-gamma activation analysis station, where the calibration is available up to 12 MeV, we derived accurate gamma-ray energies and relative intensities for these radionuclides and subsequently used them for broad energy-range efficiency and nonlinearity calibration of NAA detectors as well as a low-level counting station

Benchmarking PGAA, in-beam NAA, reactor-NAA and handheld XRF spectrometry for the element analysis of archeological bronzes

Novel detection strategies were developed to improve the PGAA methodology in the analysis of bronze and brass objects. Instrumental neutron activation analysis and X-ray fluorescence were also involved in this study for comparison. The approach was tested on a set of IRMM-certified copper alloys. Reference values for the concentrations of four major additive components (As, Zn, Sn, and Pb) were compared with the results obtained by the involved methods. The bias observed between the reference Sn values and the initial PGAA results was successfully addressed by considering the interference of this line with low intensity copper prompt gamma peaks. In this report results are presented, and the analytical merits are compared

Elemental Characterization of Romanian Crop Medicinal Plants by Neutron Activation Analysis

The metallic elements concentrations of medicinal plants (coriander, dill, Echinacea, lavender, chamomile, mint, and plantain, used for phytopharmaceutical products), cultivated in unpolluted region, were analyzed by neutron activation analysis. The essential nutrients, macro-, micro-, and trace elements (K, Ca, Mg, Na, Fe, Mn, Rb, Sr, and Zn), potentially toxic elements (Al, As, Ba, Co, Sb, Cr, and V), and rare earth elements were monitored and were compared with those presented in the literature. An estimation of their contributions to intake and toxicity for a person was made, which revealed that (a) teas prepared from the examined plants represent useful contribution to the food provided intake of three essential macronutrients (K, Ca, and Mg); (b) the Cu, Mn, Rb, Sr, Zn, and rare earths levels are normal or low; (c) the quantities of As, Ba, Co, Sb, Cr, and V do not represent toxicological concerns; (d) the examination of the estimated Al and Fe quantities recovered in infusions in the conditions of usual daily tea consumption is below the Tolerable Daily Intake values. The strategy of cultivation of medicinal plants in unpolluted areas is efficient and beneficial. However, individual plants ability to concentrate preferentially certain elements suggests controlling the contamination level of raw materials