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Objective: To investigate the content of rare earth elements(REs)in blood and hair of residents in a RE mining area in Northwest Hubei, and evaluate the impact of REs on the health status of local residents., Methods: A total of 191 residents from the core area of RE mining areas and 186 residents from non RE mining areas, aged 20-69, were selected. The content of REs in the blood and hair of the survey subjects was measured using inductively coupled plasma mass spectrometry, and compared with existing literature values. At the same time, blood tests and questionnaire surveys will be conducted on the health status of residents to examine whether human RE enrichment can lead to endemic diseases., Results: The average total content of REs in the blood of residents in the mining area was 60.22 ng/mL, which was 3.35 times that of the control area; The average total content of REs in hair was 1197.91 ng/g, which was 6.32 times higher than the control area. As age increasing, the abundance of REs in the blood and hair of both men and women in mining areas increased. The proportion of Yttrium and Scandium in the blood and hair were much higher than that in the soil. Compared to hair, Yttrium and Scandium were more easily enriched in the blood. There was no significant difference in the probability of fatty liver, hepatitis B, hypoglycemia, hypotension, hypertension and heart disease and the average life span between residents in RE mining areas and those in the control area., Conclusion: The high daily average dietary intake of REs in residents leads to a relatively large accumulation of REs in human blood and hair, but no significant and substantial human health damage has been found at present.

Canada has recently invested in the large-scale exploitation of scandium oxide. However, there are no studies available to date to understand its toxicokinetics in the animal or human body, which is necessary to assess exposure and health risks. The aim of this research was to investigate the toxicokinetics of absorbed scandium oxide (Sc 2 O 3 ) using the rat as an experimental model. Male Sprague-Dawley rats were injected intravenously with 0.3 or 1 mg Sc 2 O 3 /kg body weight (bw). Blood and excreta (urine and feces) were collected sequentially during a 21-day period, and main organs (liver, spleen, lungs, kidneys, brain) were withdrawn at sacrifice on day 21. Inductively coupled plasma-mass spectrometry (ICP-MS) was used for the measurement of Sc element in the different samples. The mean residence time (MRT IV ) calculated from the blood profile was 19.7 ± 5.9 h and 43.4 ± 24.6 h at the lower and higher doses, respectively. Highest tissue levels of Sc were found in the lungs and liver; respective lung values of 10.6 ± 6.2% and 3.4 ± 2.3% of the Sc dose were observed at the time of sacrifice while liver levels represented 8.9 ± 6.4% and 4.6 ± 1.1%. Elimination of Sc from the body was not complete after 21 days. Cumulative fecal excretion over the 21-day collection period represented 12.3 ± 1.3% and 5.9 ± 1.0% of the lower and higher Sc doses, respectively, and showed a significant effect of the dose on the excretion; only a small fraction of the Sc dose was recovered in urine (0.025 ± 0.016% and 0.011 ± 0.004% in total, respectively). In addition to an effect of the dose on the toxicokinetics, results highlight the importance of the lung as a site of accumulation and retention of Sc 2 O 3 , which raises the question of the risks of effects related to respiratory exposure in workers. The results also question the relevance of urine as a matrix for biological exposure monitoring. A more in-depth inhalation toxicokinetic study would be necessary., Competing Interests: Declaration of Competing Interest There are no competing interests., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

In this work, a highly sensitive immunochromatographic test strip (ITS) based on Scandium-Tetrakis (4-carboxyphenyl) porphyrin (TCPP) metal-organic framework nanocubes (ScTMNs) was developed for ultrasensitive and facile visual determination of imidacloprid (IDP). TCPP as the porphyrin-based planar ligand and Sc 3+ as the metal center were applied to form the ScTMNs via coordination chelation. Giving the credit to its excellent optical characteristics, strong affinity with monoclonal antibodies, and favorable biocompatibility, the ScTMNs was selected as a signal tag. Under optimized conditions, the ITS exhibited a great liner relationship in the range of 0.04-3 ng/mL and the detection limit was 0.04 ng/mL for the IDP detection. Additionally, IDP was successfully detected in tomatoes, millet, corn and carrot samples with satisfied recoveries. To the best of our knowledge, this is the first time that ScTMNs have been used in immunochromatography which are expected to have potential applications in detection of other substances., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

At present, lasers are increasingly used in the oral clinical field, and research and applications in dental hard tissue treatment are also increasing. The effect of laser etching dentin on the bonding strength of composite resin reported in the literature is still inconclusive. The purpose of this review was to evaluate whether laser etching can improve the immediate and long-term bonding strength of dentin and investigate the effect of different types of adhesives on the bonding strength of dentin. Two reviewers performed a literature search up from January 2012 to November 2021 in four databases: MEDLINE (PubMed), Web of Science, EMBASE, and the Cochrane Library. A total of 25 studies were included in the meta-analysis. The Cochrane Collaboration Bias Risk Assessment tool was used to evaluate the quality of the included literature, and an analysis was carried out using Review Manager Software version 5.3. The aging bond strength of dentin after erbium (Er): yttrium aluminum garnet (YAG) laser treatment was significantly lower than that of dentin in the bur group (P < 0.00001). At the same time, the bond strength of dentin immediately and aging after (Er), chromium-doped (Cr): yttrium scandium gallium garnet (YSGG) laser treatment was lower than that of dentin in the bur group (P < 0.05). There was no significant difference in the immediate and aging bonding strength among samples in the Er: YAG laser, Er, Cr: YSGG laser, and blank control groups (no laser or bur). The aging bond strength of samples after neodymium-doped (Nd): YAG laser treatment was higher than that of samples in the blank control group (P < 0.05); in addition, the performance of self-etching adhesive was slightly better than that of acid etching adhesive. Regardless of the applied surface treatment and the adhesive employed, dentin after aging showed significant bond degradation (P < 0.05). There was high heterogeneity of bond strength between different groups, and the small number of studies and the contradictory results may be the main reasons for this outcome., (© 2022. The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature.)

44 Sc is an increasingly investigated positron emitter for use in positron emission tomography (PET) imaging. However, 44 Sc is a non-pure positron emitter, since prompt photons are co-emitted during the decay process. This study investigates coincidence energy spectra of 44 Sc and its impact on PET quantification on a preclinical and clinical PET system in comparison with 18 F. The raw data of the coincidence events revealed characteristic differences comparing the photon energy distribution of 44 Sc and 18 F. Due to prompt gamma emission of 44 Sc, activity recovery is underestimated on PET systems. However, clinical PET imaging of 44 Sc with acceptable quantitative accuracy appears feasible by using a single, constant correction factor., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

A simple and efficient separation method of carrier-free 47 Sc from neutron irradiated titanium target using a novel chitosan-acrylic acid/multiwalled carbon nanotubes (CS-AA/MWCNTs) composite was established. The synthesis of the CS-AA/MWCNTs composite was achieved using gamma radiation-induced template polymerization. The grafting efficiency (GE%) of AA on CS onto the surface of f-MWCNTs reached a maximum of~84% under the optimized conditions (30 wt% CS, 1.0 wt% AA, 0.15 wt% f-MWCNTs, >0.2 wt% N,N'-Methylenebisacrylamide (NMBA), and irradiation dose ~25 kGy). Different analyses (FT-IR, SEM, TGA and DTA) were examined for confirming the structural morphology and mechanical properties of the new synthesized composite. Interestingly, the CS-AA/MWCNTs composite depicted a selective adsorption of Sc(III) rather than Ti(IV) ions at pH 5 with adsorption efficiency of ~93.93%. The ionic exchange separation of no-carrier-added (NCA) 47 Sc(III) from irradiated TiO 2 target on CS-AA/MWCNTs composite packed column efficiently eluted 47 Sc(III) by 91 ± 0.8% using 1 M HCl solution. The quality control tests (radionuclidic, radiochemical, and chemical purities) for the eluted 47 Sc(III) clarified its high purity and validity for cancer theranostics., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The mobility (fractionation) of rare earth elements (REEs) and their possible impacts on ecosystems are still relatively unknown. Soil samples were collected from two sites in central Serbia, an unpolluted mountain region (site 1) and a forest near a city (site 2). In order to investigate REE fractions (acid-soluble/exchangeable, reducible, oxidizable, and residual) in soils, BCR sequential extraction was performed. Additionally, the content of REEs was also determined in stipes and caps of the mushroom Macrolepiota procera, growing in the observed sites. Sc, Y, and lanthanide contents were determined by inductively coupled plasma mass spectrometry (ICP-MS), and results were subjected to multivariate data analysis. Application of pattern recognition technique revealed the existence of two distinguished clusters belonging to different geographical sites and determined by greater levels of Sc, Y, and lanthanides in Goč soil compared to Trstenik soil. Additionally, PCA analysis showed that REEs in soil were concentrated in two groups: the first consisted of elements belonging to light REEs and the second contained heavy REEs. These results suggest that the distribution of REEs in soils could indicate the geographical origin and type of soil. The bioconcentration factors and translocation factors for each REE were also calculated. This study provides baseline data on the rare earth element levels in the wild edible mushroom M. procera, growing in Serbia. In terms of bioconcentration and bioexclusion concept, Sc, Y, and REEs were bioexcluded in M. procera for both studied sites.

Studies conducted in China linked selenium deficiency to higher risk of esophageal squamous cell carcinoma (ESCC), but this has not been widely tested outside that selenium-deficient region. The aim of this study was to investigate the association between selenium and other mineral concentrations in toenails and risk of ESCC in a region with high incidence rates. In this nested case-control study, we identified 222 cases of ESCC from the Golestan Cohort Study, Iran, which has followed up 50,045 participants since enrollment (2004-2008). We randomly selected one control for each case matched by age and sex, using incidence density sampling. We used toenail samples collected at baseline to measure the concentration of selenium, zinc, chromium, mercury, and scandium using instrumental neutron activation analysis. Multivariate adjusted logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals. Median nail selenium, zinc, chromium, and mercury levels were 1.01, 74.59, 0.77, and 0.018 μg/g in cases and 1.02, 75.71, 0.71, and 0.023 μg/g in controls, respectively. The adjusted odds ratios comparing each fourth quartile of mineral status versus the first quartile were as follows: selenium = 0.78 (95% CI, 0.41-1.49); zinc=0.80 (95% CI, 0.42-1.53); chromium = 0.91 (95% CI, 0.46-1.80); and mercury=0.61 (95% CI, 0.27-1.38), and all trend tests were non-significant. The nail selenium concentration in our controls reflects relatively high selenium status. No evidence of association between selenium or chromium concentrations in toenails and the risk of ESCC was detected in this population., (© 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

The half-life of the positron-emitter (44)Sc has been determined by following the decay rate with two measurement systems; an Ionisation Chamber and a HPGe detector. The combination of seven results gives a value of T1/2=4.042 (25)h, about 2% higher than the recommended value of T1/2=3.97 (4)h (Browne, 2011) and with a lower uncertainty. This radionuclide has also been standardised by coincidence counting, and liquid scintillation counting techniques. A (44)Ti/(44)Sc generator developed at CIEMAT was used to obtain the (44)Sc solutions used in all measurements., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

We investigated the effect of fluoride complexation on scandium accumulation by two unicellular algae, Chlamydomonas reinhardtii and Pseudokirchneriella subcapitata. This trivalent metal was selected for its chemical similarities with aluminum and for its convenient radioisotope (Sc-46), which can be used as a tracer in short-term bioaccumulation studies. Scandium surface-bound concentrations (Sc(ads)) and uptake fluxes (J(int)) were estimated in the two algae over short-term (<1 h) exposures at pH 5 and in the presence of 0 to 40 μM F(-). Although the computed proportion of dissolved Sc(3+) dropped from 20% to 0.01% over this [F(-)] range, Sc(ads) and J(int) values for both algae decreased only slightly, suggesting a participation of Sc fluoro-complexes in both processes. Surface adsorption and uptake of fluoride complexes with aluminum have been reported in the literature. These observations are not taken into account by current models for trace metal bioaccumulation (e.g., the biotic ligand model). Results from a previous study, where the effects of pH on Sc uptake were investigated, suggested that Sc hydroxo-complexes were internalized by C. reinhardtii. There is thus growing evidence that the free ion concentration may not be adequate to predict the accumulation of Sc (and potentially of other trivalent metals) in aquatic organisms.

An on-line scandium preconcentration and determination system implemented with inductively coupled plasma optical emission spectrometry associated with flow injection was studied. Trace amounts of scandium were preconcentrated by sorption on a minicolumn packed with oxidized multiwalled carbon nanotubes, at pH 1.5. The retained analyte was removed from the minicolumn with 30% (v/v) nitric acid. A total enrichment factor of 225-fold was obtained within a preconcentration time of 300 s (for a 25 mL sample volume). The overall time required for preconcentration and elution of 25 mL of sample was about 6 min; the throughput was about 10 samples per hour. The value of the detection limit was 4 ng L(-1) and the precision for 10 replicate determinations at 100 ng L(-1) Sc level was 5% relative standard deviation, calculated from the peak heights obtained. The calibration graph using the preconcentration system was linear with a correlation coefficient of 0.9996 at levels near the detection limits up to at least 10 mg L(-1). After optimization, the method was successfully applied to the determination of Sc in an acid drainage from an abandoned mine located in the province of San Luis, Argentina., (Copyright © 2014 Elsevier B.V. All rights reserved.)

To efficiently obtain multiple-quantum magic-angle spinning (MQMAS) spectra of the nuclide 45Sc (I=7/2), we have combined several previously suggested techniques to enhance the signal-to-noise ratio and to improve spectral resolution for the test sample, scandium sulphate pentahydrate (ScSPH). Whereas the 45Sc-3QMAS spectrum of ScSPH does not offer sufficient resolution to clearly distinguish between the 3 scandium sites present in the crystal structure, these sites are well-resolved in the 5QMAS spectrum. The loss of sensitivity incurred by using MQMAS with 5Q coherence order is partly compensated for by using fast-amplitude modulated (FAM) sequences to improve the efficiency of both 5Q coherence excitation and conversion. Also, heteronuclear decoupling is employed to minimise dephasing of the 45Sc signal during the 5Q evolution period due to dipolar couplings with the water protons in the ScSPH sample. Application of multi-pulse decoupling schemes such as TPPM and SPINAL results in improved sensitivity and resolution in the F(1) (isotropic) dimension of the 5QMAS spectrum, the best results being achieved with the recently suggested SW(f)-TPPM sequence. By numerical fitting of the 45Sc-NMR spectra of ScSPH from 3QMAS, 5QMAS and single-quantum MAS at magnetic fields B(0)=9.4 T and 17.6 T, the isotropic chemical shift delta(iso), the quadrupolar coupling constant chi, and the asymmetry parameter eta were obtained. Averaging over all experiments, the NMR parameters determined for the 3 scandium sites, designated (a), (b) and (c) are: delta(iso)(a)=-15.5+/-0.5 ppm, chi(a)=5.60+/-0.10 MHz, eta(a)=0.06+/-0.05; delta(iso)(b)=-12.9+/-0.5 ppm, chi(b)=4.50+/-0.10 MHz, eta(b)=1.00+/-0.00; and delta(iso)(c)=-4.7+/-0.2 ppm, chi(c)=4.55+/-0.05 MHz, eta(c)=0.50+/-0.02. The NMR scandium species were assigned to the independent crystallographic sites by evaluating their experimental response to proton decoupling, and by density functional theory (DFT) calculations using the PAW and GIPAW approaches, in the following way: Sc(1) to (c), Sc(2) to (a), and Sc(3) to (b). The need to compute NMR parameters using an energy-optimised crystal structure is once again demonstrated., (2009 Elsevier Inc. All rights reserved.)

Soil sampling and analysis for radionuclides after an accidental or routine release is a key factor for the dose calculation to members of the public, and for the establishment of possible countermeasures. The IAEA organized for selected laboratories of the ALMERA (Analytical Laboratories for the Measurement of Environmental Radioactivity) network a Soil Sampling Intercomparison Exercise (IAEA/SIE/01) with the objective of comparing soil sampling procedures used by different laboratories. The ALMERA network is a world-wide network of analytical laboratories located in IAEA member states capable of providing reliable and timely analysis of environmental samples in the event of an accidental or intentional release of radioactivity. Ten ALMERA laboratories were selected to participate in the sampling exercise. The soil sampling intercomparison exercise took place in November 2005 in an agricultural area qualified as a "reference site", aimed at assessing the uncertainties associated with soil sampling in agricultural, semi-natural, urban and contaminated environments and suitable for performing sampling intercomparison. In this paper, the laboratories sampling performance were evaluated.

The Gascogne region (SW of France) is cultivated for more than 75% of the area. 83 samples of stream bed sediments were collected in three main Gascogne river basins (Gers, Save and Touch, left tributaries of the Garonne river) to evaluate the impact of agricultural practices on trace elements behavior. Eight potential harmful elements (PHE) (Cr, Co, Ni, Cu, Zn, As, Cd and Pb), four reference elements for normalization (Sc, Cs, Al and Fe) and four major elements (Mn, Ca, Mg and P) were considered. The average trace element concentrations in the fine fractions (<63 microm) are in the decreasing order: Zn>Cr>Ni>Pb>Cu>Co>As>Sc>Cs>Cd. Geochemical investigations and an original approach combining regression analysis and chemical sequential extraction allowed to select the most adequate reference material (regional molasse) and reference element (Cs) for normalization procedure. The enrichment factor (EF) is generally lower than 2.5, particularly for Cr, Ni, Cu, As, Zn; however, 23% of the sampling stations are more contaminated (2.5

In the frame of the international SOILSAMP project, funded and coordinated by the National Environmental Protection Agency of Italy (APAT), uncertainties due to field soil sampling were assessed. Three different sampling devices were applied in an agricultural area using the same sampling protocol. Cr, Sc and Zn mass fractions in the collected soil samples were measured by k(0)-instrumental neutron activation analysis (k(0)-INAA). For each element-device combination the experimental variograms were calculated using geostatistical tools. The variogram parameters were used to estimate the standard uncertainty arising from sampling. The sampling component represents the dominant contribution of the measurement uncertainty with a sampling uncertainty to measurement uncertainty ratio ranging between 0.6 and 0.9. The approach based on the use of variogram parameters leads to uncertainty values of the sampling component in agreement with those estimated by replicate sampling approach.

The 8 and 27 keV monoenergetic neutron calibration fields have been developed by using (45)Sc(p, n)(45)Ti reaction. Protons from a 4-MV Pelletron accelerator are used to bombard a thin scandium target evaporated onto a platinum disc. The proton energies are finely adjusted to the resonance to generate the 8 and 27 keV neutrons by applying a high voltage to the target assemblies. The neutron energies were measured using the time-of-flight method with a lithium glass scintillation detector. The neutron fluences at a calibration point located at 50 cm from the target were evaluated using Bonner spheres. A long counter was placed at 2.2 m from the target and at 60 degrees to the direction of the proton beam in order to monitor the fluence at the calibration point. Fluence and dose equivalent rates at the calibration point are sufficient to calibrate many types of the neutron survey metres.

Using ICP-SMS and the clean lab methods and procedures developed for determining trace element concentrations in polar snow and ice, a lower limit of detection (LOD) of 30 pg l(-1) for Sb and 5 pg l(-1) for Sc was achieved, allowing the natural abundances of Sb and Sc to be measured in pristine groundwaters. Water samples were collected from natural flows and wells between Elmvale and Wyevale in Springwater Township, Ontario, Canada. The water in this region is derived from chemical reactions between meteoric fluids and the Quaternary sediments which cover the bedrock (dolomitic limestone) to depths of more than 100 m. The chemical composition of these waters (pH 8) is primarily a reflection of reactions between the percolating fluids with calcite and dolomite. The maximum concentration of Sb was 5.0 ng l(-1), and the average of all samples collected was 2.2 +/- 1.2 ng l(-1) (n = 34). The average concentration of Sc was 8.6 +/- 4.7 ng l(-1) (n = 28). The paucity of published Sb concentration data available for comparison is probably because most of the analytical methods commonly used to date, including GFAAS, HG-AAS, HG-AFS, INAA, and ICP-QMS, have lower limits of detection which are inadequate for reliably determining the natural abundance of Sb in many uncontaminated groundwaters. Also, the measurement of extremely low concentrations of Sb requires extra care to avoid possible contamination. Given the extensive use of Sb in plastics, we show that some of the containers used to collect and store samples, and for handling and preparing samples for chemical analyses, may be important sources of contamination in the laboratory. The Sb and Sc concentrations reported here should serve as reference values for this region, against which contamination by various human impacts in future could be compared.

Adopting recently developed clean laboratory techniques, antimony (Sb) and scandium (Sc) deposition were measured in a 63.72 m-long ice core (1842-1996) and a 5 m deep snow pit (1994-2004) collected on Devon Island, Canadian High Arctic. Antimony concentrations ranged from 0.07 to 108 pg g(-1) with a median of 0.98 pg g(-1)(N= 510). Scandium, used as a conservative reference element, revealed that dust inputs were effectively constant during the last 160 years. The atmospheric Sb signal preserved in the ice core reflects contamination from industrialisation, the economic boom which followed WWII, as well as the comparatively recent introduction of flue gas filter technologies and emission reduction efforts. Natural contributions to the total Sb inventory are negligible, meaning that anthropogenic emissions have dominated atmospheric Sb deposition throughout the entire period. The seasonal resolution of the snow pit showed that aerosols deposited during the Arctic winter, when air masses are derived mainly from Eurasia, show the greatest Sb concentrations. Deposition during summer, when air masses come mainly from North America, is still enriched in Sb, but less so. Snow and ice provide unambiguous evidence that enrichments of Sb in Arctic air have increased 50% during the past three decades, with two-thirds being deposited during winter. Most Sb is produced in Asia, primarily from Sb sulfides such as stibnite (Sb2S3), but also as a by-product of lead and copper smelting. In addition there is a growing worldwide use of Sb in automobile brake pads, plastics and flame retardants. In contrast to Pb which has gone into decline during the same interval because of the gradual elimination of gasoline lead additives, the enrichments of Sb have been increasing and today clearly exceed those of Pb. Given that the toxicity of Sb is comparable to that of Pb, Sb has now replaced Pb in the rank of potentially toxic trace metals in the Arctic atmosphere.

This paper describes the determination of trace La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Yb and Lu in the sample, using carbon powder, potassium sulfate, barium sulfate, strontium sulfate, and scandium chloride as buffer, by atomic emission spectrometry (AES). Scandium was selected as internal standard line. Sample separation and chemical treatment were not required. The sample was directly loaded into ordinary electrode. The method is simple, rapid and accurate. The determination requirement and influence factors were studied. A new method was developed for the determination of ten rare earth elements, for which the detection limit is smaller than 0.030%, and the range of the recovery is 94%-105%. The results of these elements in standard sample are in agreement with certified values, and the RSD is smaller than 5% (n = 9). The method has been applied to the determination of ten rare earth elements with satisfactory results.

The complexes of chromium(III), scandium(III) and yttrium(III) formed by 1-hydroxy-2-naphthoic acid (1,2-HNA: H2L) and 3-hydroxy-2-naphthoic acid (3,2-HNA: H2L) were investigated by potentiometry and spectroscopy at 25+/-0.1 degrees C and at an ionic strength of 0.1 M KNO3 in 50% ethanol-water (v/v) medium. The stoichiometries of these three M(III) complexes formed with these hydroxy-naphthoic acids and with hydroxo ion were defined and their formation constants were determined and compared. Thus, the removing capacities of these ligands could be examined by calculating the equilibrium concentration of Cr(III) that exists in the discharge water of various industries since Cr(III) ions are the main pollutants present during waste water treatment in our city, Bursa.

A new method for inductively coupled plasma atomic emission spectrometry (ICP-AES) determination of trace Sc and Y, based on gaseous compound introduction into the plasma as their thenoyltrifluoroacetone (TTA) complexes by electrothermal vaporization was developed. Using the reagent TTA as chemical modifier can not only enhance the analytical signals, but also reduce the vaporization temperature. At a temperature of 1,000 degrees C the trace Sc and Y can be vaporized completely into ICP. The factors affecting the formation of the chelate and its vaporization behavior, such as drying time, vaporization temperature/time, reaction medium and the amount of TTA, were investigated in detail. Under the optimized conditions (drying temperature/time 100 degrees C/10 s, vaporization temperature/time 1,000 degrees C/4 s), the limits of detection for Sc and Y were 19 pg and 34 pg (3sigma), respectively, and the relative standard deviations for Sc and Y were 4.2% (cSc=0.2 microg mL(-1); n=7) and 2.6% (cY=0.5 microg mL(-1); n=7). The linear ranges of the calibration graphs cover three orders of magnitude. The method was applied to the analysis of the biological reference materials (GBW 07602, bush branches and leaves; GBW 07604, poplar leaves), and the results obtained were in good agreement with the certified values.

The association between scandium status and risk of acute myocardial infarction (MI) was examined in a multicentre case control study in 10 centres from Europe and Israel. Scandium in toenails was assessed in 684 cases and 724 controls less than 70 years of age. Mean concentrations of toenail scandium were 6.74 micro/kg in cases and 7.75 microg/kg in controls. Scandium among controls, adjusted for age and centre was positively associated with concentrations of lycopene and oleic acid in adipose tissue (P = 0.002 for both nutrients). Pearson correlations adjusted for age and centre were significant (P < 0.05) between scandium and lycopene (r = 0.08), zinc (r = 0.08), mercury (r = 0.18) and oleic acid (r = 0.21). Overall, cases had lower levels of scandium than controls after adjustment for age and centre (case control ratio, 0.87; 95% CI 0.79-0.96). This association persisted after adjustment for other cardiovascular risk factors (case-control ratio 0.88; 95% CI, 0.79-0.98). The risk of MI at high scandium levels was reduced after adjustment for age and centre (P-trend = 0.04). Further adjustments for BMI, history of hypertension, smoking, alcohol intake, diabetes, family history of CHD, alpha-tocopherol, beta-carotene, lycopene, selenium and mercury slightly attenuated this trend (P = 0.055). Our results suggest that toenail scandium level is associated with a reduced risk of acute MI, but we are uncertain whether this element can really play a protective role in the development of CHD. Without an identified plausible mechanism, these results should be regarded as preliminary and should be tested in future studies.

The question of whether or not higher-order (five-, seven- and nine-quantum) multiple-quantum magic angle spinning (MQMAS) experiments yield isotropic NMR spectra of half-integer quadrupolar nuclei with higher resolution than the basic three-quantum MAS experiment is examined. The frequency dispersion is shown theoretically to be greatly increased in higher-order MQMAS spectra, but it is argued that whether or not this translates into an increase in resolution depends upon the ratio of the homogeneous to inhomogeneous contributions to the isotropic linewidth. Experimentally, it is demonstrated using three-, five- and seven-quantum 45Sc MAS NMR and three- and five-quantum 27Al MAS NMR of crystalline samples that higher-order MQMAS experiments can yield a real and useful increase in resolution but that, owing to the presence of inhomogeneous broadening in the isotropic spectra, this increase is less than the theoretically predicted value. A number of practical issues relating to resolution in MQMAS NMR are also pointed out.

Peat cores taken from eight Swiss peatlands were used to calculate inventories of anthropogenic Pb using either Sc or Zr to quantify Pb derived from rock weathering. The shapes of the Pb/Sc and Pb/Zr profiles suggest that Pb was supplied exclusively by atmospheric deposition at all sites. At one of the sites (Etang de la Gruère), anthropogenic Pb was calculated using both Sc and Zr as the conservative reference element. Lithogenic Pb determined using Sc was twice that obtained using Zr, possibly because Zr resides only in zircons which are dense compared to pyroxene and amphibole which are the main Sc-bearing phases in the earth's crust. However, the inventory of 'natural' Pb (supplied almost entirely by soil dust) is dwarfed by the anthropogenic inventory such that anthropogenic Pb calculated using Sc and Zr agree to within 5%. The total amount of anthropogenic Pb accumulated in the bogs was calculated by simply adding the mass of anthropogenic Pb for each peat slice over the length of each core. Cumulative, anthropogenic Pb calculated in this way ranged from 1.0 to 9.7 g/m2 and showed pronounced regional differences: the site south of the Alps (Gola di Lago in Canton Ticino) with direct exposure to the heavily industrialized region of northern Italy received nearly 10 times more anthropogenic Pb as the sites in more remote alpine regions (Schöpfenwaldmoor in Canton Berne, and Mauntschas in Canton Grisons). The approach used here to calculate cumulative, anthropogenic, atmospheric Pb (CAAPb) is simple and robust, independent of the chronology of Pb deposition, and makes no assumptions about the immobility of Pb within the peat profile. Given the worldwide distribution of peat bogs, it should be possible to undertake continental and global inventories of atmospheric metal deposition, for both the natural and anthropogenic components of most trace metals of environmental interest.

Heavy metals and rare earth elements in two types of cigarettes were studied. The contents of trace elements were determined by using delayed neutron activation analysis. In the present study 11 elements have been detected in popular and fine brand cigarettes marketed in Egypt. Evaluation of these elements with their potential hazards for smokers is briefly discussed. The material balance (source and sink) for each element was determined. Also the ratio of element recovery to the total amount was assessed.

Seven representative wood species constituting Caatinger forest in north-east Brazil were chosen to analyze La, Ce, Sm, Eu, Yb, Sc, and Al by instrumental neutron activation analysis (INAA). Soil profiles were prepared where the trees were downed. Then soil and root samples from each horizontal soil layer, as well as the upper part of the wood, ground-level bark, and the bark at 1 m above were collected. In woods, the rare earth element (REE) was found to be mainly accumulated in root, which concentration was in the same order as that of soil. In all samples, concentration of La and Ce were found to be about ten times higher than those of the other REEs. The REE accumulation became higher, in both root and soil, in the order of La, Ce, and Sm. The partition rate of La and Eu was higher from soil to root, whereas Ce tended to be concentrated from root to bark. In the case of bark, there was no tendency of specific REE accumulating from ground level to the upper part. The correlation of La concentration to the other REE was higher in root than that of corresponding soil. Roots also showed higher correlation of REE to Al and Sc than that of soil or bark.

Scandium, gallium and vanadium contents in plants is on the ppm level, although plants from industrial areas can show higher concentrations of these elements. In Department of Analytical Chemistry of Silesian University there have been elaborated new, sensitive, spectrophotometric methods of determination of scandium, gallium and vanadium using Chrome Azurol S (CAS) and Sterinol (ST). The aim of this study was the application of these methods in analysis of cultivated plants from polluted regions. White cabbage from Upper Silesia was chosen. Because the spectrophotometric methods are not selective, scandium, gallium and vanadium should be preliminary separated from interfering elements. The solvent reaction was applied for the isolation from main and trace components of investigated material. Tienoiltrifluoracetone solution in xylene was used for the extraction of scandium, mesithyloxide for vanadium and n-butyl acetate--for gallium. Interfering and not separated Fe(III) was isolated using the extraction with acetylacetone solution in CHCl3 in the case of scandium and the reduction to Fe(II) by ascorbic acid in the case of gallium and vanadium. Due to influence of Fe(II) on the vanadium determination, KCN was used as a masking agent directly after the reduction. Scandium, gallium and vanadium were determined in 6 independent samples of white cabbage after dry or wet mineralization and contents of these leemnets were found from calibration graphs. Obtain results were checked by the internal standard addition method and Atomic Emission Spectrometry Method (ICP AES). The amounts of gallium and vanadium in white cabbage from Upper Silesia District determined by elaborated methods are in good correlation with a literature data, although the contents of vanadium are on the toxic level. The scandium concentration is higher than in plants from not industrial areas. The standard recovery is satisfactory. The Atomic Emission Spectrometry Method gave comparable results. The proposed the spectrophotometric methods are sensitive, precise and economical too, because they require only small amounts of reagents and simple not expensive apparatus. The methods can be recommended for many laboratories to the analytical control of white cabbage and after adaptation to the other plant material analysis.

Analysis of variance, analysis of covariance, correlation coefficient, multiple correlation, and partial correlation coefficient statistical tests were applied to Cs, Cr, Co, Fe, Rb, Sc, Se, and Zn content in human ovaries in order to evaluate statistically the possible relationships between these trace elements at: the ovary as an organ, each ovarian phase separately, each morphological part independent of the ovarian phase, and between cortex and medulla within the ovarian phases. The element Cs seems to have a homogeneous distribution between cortex and medulla within reproductive and menopausal phase. Zinc shows a trend to have an antagonistic relation with Cs, Cr, Co, and Fe during fetal and reproductive phases and not during menopausal phase. The relationship between Zn and Cs when Fe is kept constant could be used as a tool for the decontamination of the ovary from an abnormal Cs content or for the inhibition of the accumulation of the same element to the ovarian tissue.

The objectives of this study were to compare four common techniques used to estimate soil mass loadings on plant surfaces and to assess the need to account for particle-size distributions of both the soil tracer and contaminant of concern within the soil. Soil loadings (g soil kg-1 dried plant) from split samples collected in a pasture near Chernobyl were estimated using soil tracers of plutonium analyzed via alpha spectroscopy (mean +/- standard error; 1.0 +/- 0.2), titanium analyzed with an inductive coupled plasma spectrometer; (3.6 +/- 0.6), and neutron activation analysis for scandium (8.1 +/- 1.6), as well as simply washing the soil off the vegetation (34.1 +/- 5.6) Differences were significant at p < 0.001. We also found that soil loading estimates from any one technique varied by a factor of 10 depending on the soil particle size used in the calculations. This was because soil loadings decreased when smaller-sized soil fractions dominated the resuspension process. However, the percent of the plant's total contamination attributable to soil loading increased with smaller soil particles. Smaller soil particles apparently contribute less to the mass of soil loading (g soil kg-1 dry plant), but more to the total plant contamination (Bq) because of the higher concentration of contaminant found in the smaller-sized soil fractions. Differences in mass loading estimates due to the technique chosen (a factor of 10), or due to differences in elemental concentration as a result of the soil particle size used in the calculation (also a factor of 10), were greater than the natural variability observed in the field (2.5).

Scandium and ash methods' performances were compared in terms of soil content assessment in sugar cane loads, emphasizing the common sampling drawbacks. Both methods are adequate for such determination in controlled conditions. The scandium has demonstrated better analytical characteristics, since it is free from interferences of cane matrix, which decreases the accuracy of the ash method in normal mill conditions.

The application of short-lived nuclides, especially in connection with the 6LiD-converter, in biological and environmental samples is demonstrated on I and Br determination in human urine, on I in pet food, and on the analysis of all the halogens in volcanic gases in a single activation. Trace element determination in lichens indicates polluted and unpolluted areas. The use of the .74-s 38mCl enables the rapid screening of great number of samples.

The endogenous concentrations of Sc, La, Ce, Sm, Eu, Tb, Yb, and Lu were determined by neutron activation analysis in up to five successive needle age classes of Norway spruce (Picea abies). Trees from nine sites over different bedrocks were sampled individually. Concentration values found are generally much lower than those reported in the literature. This is attributed to the careful removal of any aerosols or soil particles from the needle surface prior to analysis. The concentration of each element increases linearly with the needle age class, i.e., the accumulation can be characterized by just one parameter, the yearly increment. This pattern is followed at small as well as at large concentrations. The accumulation behavior of the investigated elements is identical to that of Si. The relative concentrations of the rare earth elements (REE) in the needles are similar to those in the earth crust. There are significant correlations between the individual REE and between Sc and La.

The concentrations of trace elements were determined in 70 wines by activation analysis and investigated as a function of location, grape variety and vintage year. It is possible using numerical taxonomy to cluster all the wines of one region by their greater similarity in trace element patterns. It is too early for a definative evaluation of the limits of this method.

Instrumental neutron activation analysis with Gamma-spectroscopy is a very sensitive method for testing trace elements. Specimens of contact tissue around 5 Blount's vitallium clamps were, after preparation at the Nuclear Research Institute Jülich irradiated with thermic neutrons and their element-specific gamma spectra were measured after 33 and 125 days. In contact tissue a significant rise in concentration of the alloy-specific elements cobalt and chromium was found. The unspecific elements silver, caesium, iron, rubidium, antimon, scandium and zink were either within or very close to the normal. The metallosis of contact tissue is due to corrosion of the surfaces of cobalt-chromium implants.

The use of the stable isotope 48Ca as a tracer in biological systems has been studied. Determination of 48Ca concentrations in samples was accomplished by proton activation via the (p,n) reaction with subsequent measurement of gamma-ray spectra from 44-h 48Sc and 4-h 44Sc. With protons of about 5.5 MeV and a Ge(Li) gamma-ray detector, and with no chemical processing of the samples, ratios of these two radioisotopes can be determined with sufficient precision to allow 48Ca tracer studies to be performed with sensitivity at least equivalent to that possible with the common 45Ca radioactive tracer.

For the detection and determination of the trace elements Ag and Sc in mature human cataractous lenses, the methods of neutron activation analysis was used. As regards Ag, attempts made in the past to establish its presence in the cataractous lens had failed, while Sc has not so far been thoroughly investigated. Our study of the two elements was also correlated to the age and sex of the patients with senile cataract. It was found that once senile cataract has fully matured, the determined trace-element concentrations no longer appear to be related to age and/or sex of the patients.

Samples of mud, water, algae and fish were collected from the Danube River and Danube Canal and analysed by neutron activation techniques for various trace metals. The study was conducted over a ten-months time period. Results show no significant variation in levels of Cr, Co, Sb, Zn, Fe and Sc during the period of study. Comparison of the results obtained for the river with those obtained for the canal indicate that, with the exception of one sampling site, there are no statistically significant differences. Generally the values lie in the range accepted as normal for most fresh water systems. One site in the canal was found to have high Cr content in the mud samples at a point where the Vienna River joins the canal.

An instrumental neutron-activated analysis was carried out to study metal content in nucleic acids preparations of the rat liver and tumour subjected to Shvets erythromyelosis. It was determined that the DNA and RNA preparations contain iron, zinc, silver, cobalt and scandium. According to the level of concentration of revealed metals are arranged in the row in the following order: iron less than zinc less than silver less than cobalt less than scandium. The iron and zinc contents in RNA is almost twice as high as those in DNA. The content shifts in some of the revealed metals (the iron and scandium contents in DNA preparation of the liver, zinc and iron contents in the DNA preparation of the tumour and zinc content in the RNA preparations of the liver) in the process of the development of leukosis are characterized by a tendency to their increase.

Introduction: People who spend their entire lives in highly industrialized regions are in danger of accumulating trace elements by inhalation as a result of the increased amounts of factory-produced smoke. In order to test the environmentally accumulated trace elements in lungs, lung samples of patients who lived their entire lives in the industrial area of Duisburg were compared with those of patients from the less industrialized areas of Cologne and surroundings., Material and Method: Five patients were studied who lived in Duisburg and died at 50-68 years but not primarily as a result of lung diseases. From each patient five samples of the left lung were removed at autopsy. Lungs from 18 patients who died in Cologne were also examined. From each of the latter 2 samples were removed from the left lung. All samples were studied by means of neutron activation analysis and the following elements analysed: Co, Fe, Rb, Se, Cr, Cs, Sb, Sc, Zn and Al. The Al-concentration was analysed only in patients aged 50-68 years., Results: The values of the non-essential Sc, Al and Cs and of the essential trace elements Co were found to be appreciably higher in the samples from Duisburg than in those from Cologne. Sc in the samples from the highly industrialized area was increased up to a factor of 100, Cs, Al and Co to a factor of 10. In the lungs of adults in Duisburg, aged 50-68 years, the concentration of Sc was more than 1,000 times greater than in lungs of children in Cologne, aged 0-10 years. In all samples from Duisburg, the rare element Eu was detectable by means of neutron activation analysis but could not be detected in a sample from Cologne., Discussion: It is likely that the different uptakes of trace elements in the lungs depend on correspondingly different concentrations of the elements in the air. The extensive accumulation, especially of the non-essential elements, in the lungs should be an incentive to examine possible detrimental effects on human health in the future. The element Sc which was strikingly accumulated in the lungs and which can be easily measured by neutron activation analysis might be used as a standard for estimating the extent of environmental pollution.

Up to 60 tissue samples were dissected from 13 human brains in defined regions and were analysed by means of neutron activation analysis for trace element concentration of cobalt, iron, rubidium, selesium, zinc, chromium, silver, cesium, antimony and scandium. It was shown that the variation in concentration of the non-essential elements in the different brain regions was greater than the corresponding variations in concentration of the essential elements. The mean values of Fe and Rb concentrations were higher in the basal ganglia than in the cortex areas. With increasing age the Fe concentration in the human brain was found to increase and that of Rb to decrease. Comparison of the trace element concentration in corresponding areas of the right and left hemispheres showed highly significant positive correlations for the essential elements. The concentration of each of the essential elements Fe, Rb and Zn was also found to differ significantly between defined functional regions. The characteristic distribution of essential trace elements in different areas is discussed in the light of known metabolic functions of these elements.