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1.
Isotopes Environ Health Stud ; : 1-15, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949391

RESUMO

For a detailed characterization of the 5.7 106 mt phosphogypsum (PG) stack in the vicinity of Bacau city, Romania, the air dose rate (ADR) was measured in 72 points covering the stack surface, while 10 samples of stack material were collected for future analysis. Radiometric determinations showed for the ADR values varying between 364 ± 53 and 489 ± 8 nSv/h, with some extreme values of 2775 ± 734 nSv/h, significantly exceeding 90 nSv/h, the average value reported for the Romanian territory. High-resolution gamma-ray spectroscopy (HRGS), performed on 10 samples collected from the entire PG stack evidenced only the presence of 226Ra as the major radioactive element with a specific activity varied between 820 ± 150 and 5278 ± 264 Bq/kg for hot spots. Further analysis performed on a similar number of samples by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDX), evidenced, beside gypsum as the main component, traces of brushite (CaHPO4·2H2O) and ardealite (Ca2(PO3OH)(SO4)·4H2O), as well as the presence of small acicular celestine (SrSO4) agglomerates. XRF determinations of the mass fractions of major elements evidenced values such as SiO2 (2.31 ± 0.73 %), TiO2 (0.07 ± 0.01 %), Al2O3 (0.17 ± 0.04 %), Fe2O3 (0.87 ± 0.18 %), MnO (0.01 ± 0.01 %), MgO (0.17 ± 0.02 %), CaO (32.5 ± 0.82 %), Na2O (0.04 ± 0.04 %), K2O (0.05 ± 0.01 %), P2O5 (2.12 ± 0.51 %), LOI (20.2 ± 0.3 %), i.e. closer to literature reported data for PG of different provenience while the data concerning the distribution of 20 trace elements, including incompatible Sc, La, Ce, and Th were relatively closer to the upper continental crust (UCC).

2.
Cureus ; 16(5): e59819, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38846242

RESUMO

Background Drug and substance abuse remains a major medical problem worldwide. Amphetamines are potent stimulants of the central nervous system. Amphetamine abuse is highly prevalent among drug-dependents. This study was conducted in Qassim, Saudi Arabia, to evaluate amphetamine's toxic effects on major and trace elements and their correlation with redox status. Methods The study involved amphetamine-only patients admitted to the Erada Rehabilitation Centre from March to October 2023. Urine samples were analysed from both normal subjects and amphetamine-dependent groups. Results Urinary sodium and chloride levels were significantly higher in the amphetamine-dependent group than in the control group, while their calcium levels decreased. Lipid peroxidase levels significantly increased in people with a substance use disorder (SUD), indicating oxidative stress. Together, their total antioxidant capacity decreased. Zinc (Zn), copper (Cu), lead (Pb), cadmium (Cd), sodium (Na), and total antioxidant capacity levels were positively correlated with lipid peroxidase. Conclusions Amphetamine-dependent people are more likely to experience a variety of health problems. This study found a direct correlation between an imbalance in major and trace elements and the redox status.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-460052

RESUMO

Aninductivelycoupledplasmamassspectrometric(ICP-MS)methodbasedonquadrupole reaction/collision ( DRC) was developed for the determination of K,Na,Ca,Mg,Al,Cu,Zn,Pb,As and Mn in food. Samples were digested with HNO3 and H2 O2 followed by dilution with ultrapure water and then analyzed directly by ICP-MS. The signal sensitivity of high concentration element ( K, Na, Ca, Mg and Al ) was suppressed easily by adjusting the voltage parameters of DRC quadrupole ( Rpa) , and the food samples could be online diluted any multiples ( i. e. from one time to million times) according to the actual need. In order to eliminate mass spectral interferences of 40 Ar35 Cl+, the operational conditions of the DRC, working with CH4 as reaction gas, were optimized for 75 As. The limits of detection for the K, Na, Ca, Mg, Al varied from 0. 013-0. 027 mg/L, and Cu, Pb, Zn, As, Mnvaried from 0. 12-0. 61 μg/L. The accurate and reliable results were obtained for validation of the ICP-MS method with food reference material according to the national standard GBW10023 , GBW10015 , GBW10018 , GBW10017 , GBW10019 and GBW10024 . As the routine method in our laboratory, the satisfactory results indicate that it has great potential for the determination of low and high concentration level elements by one single analysis in various samples.

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