scholarly journals Baromembrane method for analysis of ultra-low concentrations of radionuclides in water samples

2020 ◽  
Vol 5 (3) ◽  
pp. 11-22
Author(s):  
M. E. Vasyanovich ◽  
A. A. Ekidin ◽  
A. V. Trapeznikov ◽  
A. P. Plataev

This paper demonstrates the use of the baromembrane method for measuring ultra-low concentrations of radionuclides in water of freshwater reservoirs. The relevance is due to the need to determine radionuclides introduction into water cooling ponds used by enterprises of nuclear fuel cycle. Radionuclides of natural and technogenic origin, not associated with enterprise discharge, are always present in water cooling ponds, forming a natural or technogenic altered background. Its presence often makes it difficult to identify contribution of enterprise’s discharge to water activity, since routine monitoring methods are characterized by a very high detection limit for radionuclides. Traditional methods for determining background radionuclides concentrations require sampling of at least 500 L of water, followed by their evaporation to get a dry residue. This procedure takes at least 5 days. It is possible to reduce time and energy spent on vaporizing hundreds of liters of water by pre-concentrating radionuclides in a smaller sample volume with the baromembrane method. To demonstrate this method, a portable installation with osmotic membranes was used being characterized with initial productivity of 6.0 L·min−1. The osmotic membranes separate source water sample into two components: demineralized permeate and concentrate, containing radioactive substances. This method allows preliminary concentration of water samples from 500 to 20 L in 10–15 hours with minimal losses of radionuclides (time period depends on water mineralization level). The method is universal; it can be used for concentration of dissolved salts of any heavy metals and other organic compounds. It allows preparation of water countable samples in much shorter time that traditional method (evaporation).

1995 ◽  
Vol 31 (5-6) ◽  
pp. 211-214
Author(s):  
P. Erb ◽  
A. M. Nasser ◽  
B. Fattal

In recent years, F+ bacteriophages were proposed by several researchers as an alternative to fecal coliforms to signal the presence of fecal pollution in water sources. The sample volume which can be monitored for the presence of bacteriophages by the conventional methods is limited to 1-10 ml. This study was conducted to test the feasibility of detecting and enumerating F+bacteriophages in large volumes of water by an MFM. A recovery of up to 100% was observed for MS2 coliphage when the pH of the water samples was adjusted to 3.5. The presence of humic acid in the water interfered with the adsorption of phages to the membrane filter. F+bacteriophages were detected in 11 out of 50(22%) water samples collected from swimming pools in Jerusalem. Total coliform were detected in only 2 out of the 50 (4%) samples. Both indicator microorganisms were detected in only one sample, suggesting the lack of correlation between their presence. The results of this study demonstrated that the MFM is a sensitive assay for detecting low concentrations of F+bacteriophages in large volumes of water.


2015 ◽  
Vol 40 (1-2) ◽  
pp. 91-96 ◽  
Author(s):  
Richard A. Bernstein ◽  
Vincenzo Di Lazzaro ◽  
Marilyn M. Rymer ◽  
Rod S. Passman ◽  
Johannes Brachmann ◽  
...  

Background: Insertable cardiac monitors (ICM) have been shown to detect atrial fibrillation (AF) at a higher rate than routine monitoring methods in patients with cryptogenic stroke (CS). However, it is unknown whether there are topographic patterns of brain infarction in patients with CS that are particularly associated with underlying AF. If such patterns exist, these could be used to help decide whether or not CS patients would benefit from long-term monitoring with an ICM. Methods: In this retrospective analysis, a neuro-radiologist blinded to clinical details reviewed brain images from 212 patients with CS who were enrolled in the ICM arm of the CRYptogenic STroke And underLying AF (CRYSTAL AF) trial. Kaplan-Meier estimates were used to describe rates of AF detection at 12 months in patients with and without pre-specified imaging characteristics. Hazard ratios (HRs), 95% confidence intervals (CIs), and p values were calculated using Cox regression. Results: We did not find any pattern of acute brain infarction that was significantly associated with AF detection after CS. However, the presence of chronic brain infarctions (15.8 vs. 7.0%, HR 2.84, 95% CI 1.13-7.15, p = 0.02) or leukoaraiosis (18.2 vs. 7.9%, HR 2.94, 95% CI 1.28-6.71, p < 0.01) was associated with AF detection. There was a borderline significant association of AF detection with the presence of chronic territorial (defined as within the territory of a first or second degree branch of the circle of Willis) infarcts (20.9 vs. 10.0%, HR 2.37, 95% CI 0.98-5.72, p = 0.05). Conclusions: We found no evidence for an association between brain infarction pattern and AF detection using an ICM in patients with CS, although patients with coexisting chronic, as well as acute, brain infarcts had a higher rate of AF detection. Acute brain infarction topography does not reliably predict or exclude detection of underlying AF in patients with CS and should not be used to select patients for ICM after cryptogenic stroke.


2015 ◽  
Vol 75 (2 suppl) ◽  
pp. 63-67 ◽  
Author(s):  
B Bergamaschi ◽  
MT Rodrigues ◽  
JVS Silva ◽  
M Kluge ◽  
RB Luz ◽  
...  

<p>It is well recognized that the classical biological and chemical markers of environmental pollution do not necessarily indicate the presence or absence of emerging threats to public health, such as waterborne viruses and genotoxicants. The purpose of this preliminary study was to evaluate the presence of material of enteroviruses (EV), rotavirus (RV) and adenovirus (AdV) and genotoxicity in water samples from points of routine monitoring of water quality in the main course of the Sinos River. The points are classified into different levels of pollution in accordance to the Brazilian federal regulations. Viral genomes from EV, AdV were detected in two of the 4 collection points regardless of the level of urbanisation of the surrounding areas. In contrast, genotoxicity was not observed in piava (<italic>Leporinus obtusidens</italic>) fingerlings cultivated on these same water samples. Results were compared with classical physical, chemical and microbiological parameters. There was no clear evidence of association between any of the classical markers and the presence of viral genomes in the water samples tested.</p>


1988 ◽  
Vol 20 (11-12) ◽  
pp. 153-159 ◽  
Author(s):  
William D. Rosenzweig ◽  
Wesley O. Pipes

In recent years various types of imperfect fungi have been isolated from water systems. Fungal spores and mycelia can be inactivated by low concentrations of chlorine in the laboratory but survive in some habitats in water distribution systems. This report describes a field study which provides evidence that some types of fungi are able to grow in water distribution systems. Replicate samples from private residences were used to demonstrate that fungal densities are sometimes much greater than the levels which could be explained by adventitious spores. The microbiological content of water samples from fire hydrants was often significantly different from that of water samples from nearby private residences. The treated water input to distribution systems was found to be significantly lower in fungus content than water from private residences. Elevated storage tanks open to the atmosphere appear to be significant sources of fungal input to some systems.


2013 ◽  
Vol 69 (2) ◽  
pp. 312-319 ◽  
Author(s):  
Cennet Karadaş ◽  
Derya Kara

A new method has been developed for the determination of rare earth elements (REEs) (Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) in water samples based on preconcentration with a mini-column packed with 6-(2-thienyl)-2-pyridinecarboxaldehyde functionalized Amberlite XAD-4 resin prior to their determination using inductively coupled plasma optical emission spectrometry (ICP-OES). The optimum experimental parameters for preconcentration of REEs, such as pH of the sample, sample and eluent flow rates and sample volume, were investigated. The optimum pH values for quantitative (90–110%) sorption of the REE ions were between 6.0 and 8.0. The elution process was carried out using 2 mL of 1.0 mol L–1 HNO3 solution. Under the optimum conditions, detection limits between 0.032 and 0.963 μg L−1 for a 10 mL sample volume and 0.006 and 0.193 μg L−1 for a 50 mL sample volume were determined. The proposed method was successfully applied to the determination of REEs in water samples with recoveries in the range of 90.1–110.5%.


1975 ◽  
Vol 32 (2) ◽  
pp. 292-294 ◽  
Author(s):  
Derek A. J. Murray

A method for analysis of low concentrations of phenols, cresols, and xylenols in water samples was developed. O-xylene was added to the sample as an internal standard and the sample was extracted once with chloroform to remove a portion of the total organic material present. The trimethylsilyl derivatives of the phenols were formed and analysis completed by gas chromatography. The method was rapid and required a minimum of sample manipulation. The lower limit of detection was 0.100 mg/liter for phenol, 0.025 mg/liter for cresols, and 0.050 mg/liter for xylenols.


2016 ◽  
Vol 10 (1) ◽  
pp. 9-14
Author(s):  
Ahmad Kakaei ◽  
◽  
Mohammad Kazemeini ◽  

Background: Heavy metals, even at low concentrations, are harmful to human health and environment. Cadmium as a heavy metal is highly toxic and can cause serious threat to living organisms. This research was designed to evaluate the adsorption potential of modified magnetic iron nanoparticles by 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol ligand for the removal of cadmium ions from water solutions. Methods: This study was conducted in Ilam Branch, Islamic Azad University, Iran, in 2014. Modified magnetic iron nanoparticle was used as adsorbent for the removal of cadmium from aqueous solution. In batch extraction, the effects of parameters like pH of sample solution (3.0-11.0), initial metal concentrations (50-300) mgL-1), contact time (1.0-10 min) and adsorbent dose (10.0-60.0 mg) were studied on the adsorption process. Modified magnetite nanoparticle was presented as the adsorbent for the removal of cadmium ions from aqueous samples and later was confirmed by flame atomic absorption spectrometry. Results: The adsorption of cadmium ions on modified magnetite nanoparticles strongly depends on pH. The experimental isothermal data were analyzed using the Langmuir and Freundlich equations. The removal process followed the Langmuir isotherm. Maximum adsorption capacity for the adsorption of cadmium ions by the sorbent was 24.09 mgg-1. Conclusion: The method was successfully applied to adsorption of cadmium in water samples with satisfactory results. Other advantages include high capacity, good stability and fast adsorption kinetics. High pre-concentration factor was obtained easily by this method (120) and low analysis cost.


2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Ahmad Hosseini-Bandegharaei ◽  
Masoud Sarwghadi ◽  
Aliasghar Heydarbeigi ◽  
Seyyed Hossein Hosseini ◽  
Mehdi Nedaie

A stable extractant-impregnated resin (EIR) containing Chrome Azurol B was prepared using Amberlite XAD-2010 as a porous polymeric support. The new EIR was employed for trace separation and preconcentration of U(VI) ion followed by spectrophotometric determination with the arsenazo III procedure. CAB/XAD-2010 exhibited excellent selectivity for U(VI) ion over coexisting ions. Experimental parameters including pH, contact time, shaking speed, and ionic strength were investigated by batch extraction methods. Maximum sorption of U(VI) ions occurred at pH 4.3–6.9. The capacity of EIR was found to be 0.632 mmol·g−1. Equilibrium was reached in 25 min and the loading half-time,t1/2, was less than 6 min. The equilibrium adsorption isotherm of U(VI) was fitted with the Langmuir adsorption model. In addition, a column packed with CAB/XAD-2010 was used for column-mode separation and preconcentration of U(VI) ion. For the optimization of the dynamic procedure, effects of sample volume, sample and eluent flow rate, eluent concentration, and its volume were investigated. The preconcentration factors for U(VI) were found out to be 160. But, for convenience, a preconcentration factor of 150 was utilized for the column-mode preconcentration. The dynamic procedure gave a detection limit of5.0×10-10 mol·L−1(0.12 μg·L−1) for U(VI) ion. The proposed dynamic method showed good performance in analyzing environmental water samples.


2021 ◽  
Author(s):  
Marianne Olsen ◽  
Rachel Hurley ◽  
Nina Buenaventura ◽  
David Eidsvoll ◽  
Hans Fredrik Braaten ◽  
...  

&lt;p&gt;Rivers have been identified as an important pathway for the release of plastic waste to the oceans, connecting land-based sources to the marine environment. Asian rivers, in particular, have been highlighted by several published studies as contributing a considerable proportion of global macro- and microplastic release. To evaluate this, several parallel projects (ASEANO, SINOPLAST, INOPOL) have commenced environmental monitoring of riverine plastic contamination in China, India, and several ASEAN countries. Monitoring is being undertaken in selected study catchments, which have been identified based on their geographical context and their relevance to global plastic contamination. They include several rivers that have been reported as being amongst the most contaminating systems in the world. Macroplastic flows in the active river channel will be assessed, as well as the role of the riverbank zone in the storage and transport of plastic waste. Monitoring of riverine microplastic contamination will also be included in some countries. The aims of this environmental monitoring is to: i) provide estimates for the flux of plastics to the ocean; ii) identify appropriate and optimum methods for routine monitoring of riverine plastic contamination; iii) supply qualitative and quantitative data on macroplastic flows and contamination to support social science research that is also taking place within these river catchments; and iv) provide data for the calibration and validation of riverine plastic transport models.&lt;/p&gt;&lt;p&gt;This presentation will give an overview of monitoring plans and preliminary findings and experiences from these ongoing projects. This will include a discussion about the ways in which monitoring methods have been adapted to river systems with different morphologies and flow regimes, and to satisfy different research questions across the projects. The complexities associated with undertaking environmental monitoring in large river systems will also be addressed.&lt;/p&gt;


2015 ◽  
Vol 13 (4) ◽  
pp. 1123-1129 ◽  
Author(s):  
C. P. Maurer ◽  
A. B. Simonetti ◽  
R. Staggemeier ◽  
C. Rigotto ◽  
L. S. Heinzelmann ◽  
...  

In the present study, molecular detection of human adenoviruses (HAdV) and enteroviruses (EV) was performed in surface water samples collected from beaches Ipanema and Lami, located on the shores of Lake Guaíba, city of Porto Alegre, RS, southern Brazil. Furthermore, water safety was evaluated by counting thermotolerant coliforms (TC), following local government regulations. A total of 36 samples were collected monthly from six different sites along the beaches. Viral genomes were found in 30 (83.3%) samples. The higher detection rate was observed for HAdV (77.8%), followed by EV (22.2%). Although low concentrations of TC have been found, the occurrence of viral genomes in water samples was frequent and may pose a potential risk of infection for people bathing in these beaches.


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