Kinds Of Environmental Samples Research Articles

Dual-mode supramolecular fluorescent probe for rapid and on-site detection of chlorpyrifos in the environment

Chlorpyrifos (CPF) as a classic organophosphorus pesticide has been widely used in agricultural applications to control insects and worms. CPF in the environment can cause deaths of diverse kinds of aquatic organism and bring a high risk to human health. Therefore, the development of effective analytical method for CPF is of great importance. In this work, a novel dual-mode albumin (ALB)-based supramolecular probe FD@ALB was designed and prepared for rapid detection of CPF in the environment. The limit of detection is 0.57 μM (∼ 0.2 ppm) with a wider detection range up to 200 μM, which is satisfactory for application. The sensing mechanism can be ascribed to CPF-induced phosphorylation of ALB, thus leading to a change in the binding microenvironment of FD dye. Moreover, the paper-based test strips were used in conjunction with the FD@ALB, realizing the portable detection of CPF. This method was demonstrated to be suitable for on-site detection of CPF in various kinds of environmental samples, including water, soil, and food samples, with the aid of a smartphone. To the best of our knowledge, this is the first analytical method achieving a combination of the rapid and ratiometric detection of CPF in the environment.

Cell-free arsenic biosensors with applied nanomaterials: critical analysis.

Arsenic is a ubiquitously found metalloid in our ecosystem because of natural and anthropogenic activities. People exposed to a higher level of arsenic become susceptible to several disorders, including cancer. According to current statistics, the population chronically exposed to arsenic has surpassed 200 million. Therefore, its detection in our environment is of great importance. There are many analytical techniques for the assessment of arsenic in different kinds of environmental samples. Among these techniques, the biosensor is considered a convenient platform and a widely applied analytical device for rapid qualitative and quantitative analysis in the field of environmental monitoring, food safety, and disease diagnosis. Today, there is a trend of including nanomaterials in sensors and biosensors because it empowers researchers to explore new arsenic detection methods and to enhance their analytical capabilities. In this review article, we summarized the latest developments in arsenic biosensors in particular with emphasis on the works based on cell-free approaches that are protein/enzyme-based, DNA-based, and aptamer-based utilizing various transduction platforms. In the meantime, we compared the capabilities that were related to these cell-free arsenic biosensors. This review article also highlights the development and application of novel nanomaterials for arsenic detection.

A semi-automated protocol for NGS metabarcoding and fungal analysis in forensic

Metabarcoding through Next Generation Sequencing (NGS) has revolutionized environmental biological studies. The availability of this technical approach has opened the opportunity for a systematic implementation of fungal metabarcoding analysis in forensics, where standardized, sensitive and reproducible protocols are highly desirable. In the present paper, a pipeline including a semi-automated molecular protocol and user-friendly bioinformatics tools are applied to several kinds of environmental samples and forensic caseworks. The identification of fungi that characterize specific environments (like Aspergillus for indoor walls, or Penicillium, Debaryomices and Wickerhamomyces for food storage) can be informative for the provenance of samples. In some situations, fungal analysis cannot allow the identification of a defined environment but seems useful to cluster samples with similar provenance. Based on these considerations, fungal analysis can be included in a wider process of non-human DNA identification in order to provide clues on sample provenance.

The precision of bacterial quantification techniques on different kinds of environmental samples and the effect of ultrasonic treatment

The precision of cell number quantification in environmental samples depends on the complexity of the sample and on the applied technique. We compared fluorescence microscopy after filtration, quantification of gene copies and the cultivation based most probable number technique for their precision. We further analyzed the effect of increasing complexity of the sample material on the precision of the different methods by using pure cultures of Pseudomonas aeruginosa, fresh water samples and sediment slurries with and without ultrasonic treatment for analyses. Microscopy reached the highest precision, which was similar between pure cultures and water samples, but lower for sediment samples due to a higher percentage of cells in clusters and flocks. The PCR based quantification was most precise for pure cultures. Water and sediment samples were similar but less precise, which might be caused by the applied DNA extraction techniques. MPN measurements were equally precise for pure cultures and water samples. For sediment slurries the precision was slightly lower. The applied ultrasonic treatment of the slurries dispersed the cell clusters and flocks, increased the precision of microscopical and MPN measurements and also increased the number of potential colony forming units. However, the culturable cell number decreased by half. For MPN quantification of viable cells in samples with a high proportion of clustered cells we therefore recommend an optimization of ultrasonic treatment and a confirmation by microscopy and cultivation to reach highest possible dispersion of the cells with a minimum of inactivation. As a result of these observations we suggest a correction factor for MPN measurements to consider the effect of sonication on complex samples. The results are most likely applicable to other complex samples such as soil or biofilms.

Fate of the chemical warfare agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX) on soil following accelerant-based fire and liquid decontamination.

In the event of alleged use of organophosphorus nerve agents, all kinds of environmental samples can be received for analysis. These might include decontaminated and charred matter collected from the site of a suspected chemical attack. In other scenarios, such matter might be sampled to confirm the site of a chemical weapon test or clandestine laboratory decontaminated and burned to prevent discovery. To provide an analytical capability for these contingencies, we present a preliminary investigation of the effect of accelerant-based fire and liquid decontamination on soil contaminated with the nerve agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX). The objectives were (a) to determine if VX or its degradation products were detectable in soil after an accelerant-based fire promoted by aviation fuel, including following decontamination with Decontamination Solution 2 (DS2) or aqueous sodium hypochlorite, (b) to develop analytical methods to support forensic analysis of accelerant-soaked, decontaminated and charred soil and (c) to inform the design of future experiments of this type to improve analytical fidelity. Our results show for the first time that modern analytical techniques can be used to identify residual VX and its degradation products in contaminated soil after an accelerant-based fire and after chemical decontamination and then fire. Comparison of the gas chromatography-mass spectrometry (GC-MS) profiles of VX and its impurities/degradation products from contaminated burnt soil, and burnt soil spiked with VX, indicated that the fire resulted in the production of diethyl methylphosphonate and O,S-diethyl methylphosphonothiolate (by an unknown mechanism). Other products identified were indicative of chemical decontamination, and some of these provided evidence of the decontaminant used, for example, ethyl 2-methoxyethyl methylphosphonate and bis(2-methoxyethyl) methylphosphonate following decontamination with DS2. Sample preparation procedures and analytical methods suitable for investigating accelerant and decontaminant-soaked soil samples are presented. VX and its degradation products and/or impurities were detected under all the conditions studied, demonstrating that accelerant-based fire and liquid-based decontamination and then fire are unlikely to prevent the retrieval of evidence of chemical warfare agent (CWA) testing. This is the first published study of the effects of an accelerant-based fire on a CWA in environmental samples. The results will inform defence and security-based organisations worldwide and support the verification activities of the Organisation for the Prohibition of Chemical Weapons (OPCW), winner of the 2013 Nobel Peace Prize for its extensive efforts to eliminate chemical weapons.

Improved assessment of pyrogenic carbon quantity and quality in environmental samples by high-performance liquid chromatography

The analysis of pyrogenic carbon (PyC) in environmental samples is of great interest, e.g. for carbon cycle assessment, (bio-)char characterization and palaeo-environmental or archeological reconstruction. Here, an HPLC method (HPLC) is presented that reproducibly quantifies benzene polycarboxylic acids (BPCA) as molecular markers for PyC in various kinds of environmental samples. It operates at low pH without requiring an organic modifier and was thoroughly tested with PyC reference materials and a peatland core that served as a feasibility and plausibility check. Compared to the established gas chromatography (GC) method, the HPLC method results in higher BPCA quantification reproducibility by showing a significantly smaller coefficient of variation (HPLC: 5%, GC: 16–23%). It works well with small sample amounts, as for instance from sediment cores and aerosol collectors, and requires less sample preparation work than the GC method. Moreover, the here presented HPLC method facilitates 13C and 14C analyses on PyC from environmental samples.

Tritium Concentration in Environmental Samples around the Rokkasho Reprocessing Plant

Aomori Prefectural Government (Aomori Pref.) and Japan Nuclear Fuel Limited (JNFL) have been carrying out tritium monitoring of many kinds of environmental samples around the Rokkasho Reprocessing Plant (RRP) as part of environmental radiation monitoring. Similarly, Aomori Pref. and Tohoku Electric Power Co., Inc. have been carrying out monitoring around the Higashidori Nuclear Power Station. Results which exceeded the background levels of environmental tritium were observed in water vapor, some seawater samples and some fish samples (measured as tissue free-water tritium(TFWT)) since the final commissioning test using actual spent nuclear fuels (Active Test) was started at the RRP on March 31 2006. Therefore, we examined causes for these results by considering the operational status of the RRP and meteorological and hydrographic conditions. The committed effective dose estimated by using the results for the effect of the RRP was far below the annual dose limit for the public (1 mSv).

Global and selective detection of organohalogens in environmental samples by comprehensive two-dimensional gas chromatography–tandem mass spectrometry and high-resolution time-of-flight mass spectrometry

We successfully detected halogenated compounds from several kinds of environmental samples by using a comprehensive two-dimensional gas chromatograph coupled with a tandem mass spectrometer (GC × GC–MS/MS). For the global detection of organohalogens, fly ash sample extracts were directly measured without any cleanup process. The global and selective detection of halogenated compounds was achieved by neutral loss scans of chlorine, bromine and/or fluorine using an MS/MS. It was also possible to search for and identify compounds using two-dimensional mass chromatograms and mass profiles obtained from measurements of the same sample with a GC × GC-high resolution time-of-flight mass spectrometer (HRTofMS) under the same conditions as those used for the GC × GC–MS/MS. In this study, novel software tools were also developed to help find target (halogenated) compounds in the data provided by a GC × GC-HRTofMS. As a result, many dioxin and polychlorinated biphenyl congeners and many other halogenated compounds were found in fly ash extract and sediment samples. By extracting the desired information, which concerned organohalogens in this study, from huge quantities of data with the GC × GC-HRTofMS, we reveal the possibility of realizing the total global detection of compounds with one GC measurement of a sample without any pre-treatment.

Study of carbon nanotubes and functionalized-carbon nanotubes as substrates for flow injection solid phase extraction associated to inductively coupled plasma with ultrasonic nebulization: Application to Cd monitoring in solid environmental samples

A research was performed to evaluate the capabilities of carbon nanotubes (CNTs) and modified CNTs to serve as sorbents for preconcentrating Cd together with on-line ultrasonic nebulization (USN)-inductively coupled plasma optical emission spectrometry (ICPOES). Three different carbon nanotubes sustrates namely, carbon nanotubes (CNTs), oxidized-carbon nanotubes (ox-CNTs) and l -alanine-carbon nanotubes (ala-CNTs) were studied systematically and the main factors influencing the preconcentration and determination of Cd were examined thoroughly. The CNTs evaluated showed dissimilar adsorption behaviors leading to increasing preconcentration factors when used in the proposed on-line solid phase extraction (SPE) system as follows: CNT < ala-CNT < ox-CNT. Aiming to achieve the best analytical performance, ox-CNTs were used as they enable quantitative retention of Cd at pH 7.0 and instantaneous elution of the analyte with 10% HNO 3. Under optimal conditions, the adsorption capacity on ox-CNTs was found to be 130 μmol g −1 and the detection limit (3σ) achieved was 1.03 μg L − 1 . The precision of the method expressed as the relative standard deviation (RSD) turned to be 3.0%. The flow injection method involving use of ox-CNTs as sorbent and USN-ICPOES for detection was successfully applied to the determination of Cd in different kinds of environmental samples.

Biomarkers at the microscopic range: ToF‐SIMS molecular imaging of Archaea‐derived lipids in a microbial mat

ABSTRACTTime‐of‐Flight Secondary Ion Mass Spectrometry (ToF‐SIMS) with a bismuth cluster primary ion source was used for analysing microbial lipid biomarkers in 10‐µm‐thick microscopic cryosections of methanotrophic microbial mats from the Black Sea. Without further sample preparation, archaeal isopranyl glycerol di‐ and tetraether core lipids, together with their intact diglycoside (gentiobiosyl‐) derivatives, were simultaneously identified by exact mass determination. Utilizing the imaging capability of ToF‐SIMS, the spatial distributions of these biomarkers were mapped at a lateral resolution of &lt; 5 µm in 500 × 500 µm2 areas on the mat sections. Using cluster projectiles in the burst alignment mode, it was possible to reach a lateral resolution of 1 µm on an area of 233 × 233 µm, thus approaching the typical size of microbial cells. The mappings showed different ‘provenances’ within the sections that are distinguished by individual lipid fingerprints, namely (A) the diethers archaeol and hydroxyarchaeol co‐occurring with glycerol dialkyl glycerol tetraethers (GDGT), (B) hydroxyarchaeol and dihydroxyarchaeol, and (C) GDGT and gentiobiosyl‐GDGT. Because ToF‐SIMS is a virtually nondestructive technique affecting only the outermost layers of the sample surface (typically 10–100 nm), it was possible to further examine the studied areas using conventional microscopy, and associate the individual lipid patterns with specific morphological traits. This showed that provenance (B) was frequently associated with irregular, methane‐derived CaCO3 crystallites, whereas provenance (C) revealed a population of fluorescent, filamentous microorganisms showing the morphology of known methanotrophic ANME‐1 archaea. The direct coupling of imaging mass spectrometry with microscopic techniques reveals interesting perspectives for the in‐situ study of lipids in geobiology, microbial ecology, and organic geochemistry. After further developing protocols for handling different kinds of environmental samples, ToF‐SIMS could be used as a tool to attack many challenging problems in these fields, such as the attribution of biological source(s) to particular biomarkers in question, or the high‐resolution tracking of biogeochemical processes in modern and ancient natural environments.

Analysis of sugars in environmental samples by gas chromatography–mass spectrometry

Many environmental samples contain complex mixtures of organic compounds with different sources, polarities and reactivities. This study reports a method for the analysis of both polar/water-soluble and apolar organic compounds in several kinds of environmental samples. The analytical method consists of extraction with a mixture of dichloromethane:methanol (2:1, v/v), silylation using BSTFA ( N,O-bis-(trimethylsilyl)trifluoroacetamide) and analysis by gas chromatography–mass spectrometry (GC–MS), a common device in chemical and environmental laboratories. Fifty individual sugar standards, including monosaccharides, sugar alcohols, anhydrosugars, disaccharides and trisaccharides, were analyzed for the determination of their fragmentation patterns and retention times. Recoveries (at three concentrations) and limits of detection (LOD) were determined for a standard mixture containing glucose (monosaccharide), sorbitol (sugar alcohol), levoglucosan (anhydrosugar) and sucrose (disaccharide), and they varied from 68 to 119% and 130 to 360 ng mL −1, respectively. The method was used for the analysis of aerosol particle, soil and sediment samples, and demonstrated its feasibility in detecting not only several important environmental sugars (e.g., glucose, fructose, inositol, mannitol, sorbitol, levoglucosan, sucrose, mycose), but also a large range of organic compound classes from other polar components (e.g., dicarboxylic acids) to apolar compounds such as n-alkanes. Therefore, the analytical method presented here demonstrated its usefulness for a better understanding of sources and transport of various organic compounds in different environmental compartments.

VARIATIONS OF THE ELEMENTAL CONCENTRATIONS IN PINE NEEDLE AND GRASS COLLECTED FROM THE AREA SURROUNDING RADIOISOTOPE WASTE TREATMENT LABORATORY

Environmental samples (rice, soil, river soil and water, running water, pine needle, milk and grass) are collected from the area surrounding Kaya Memorial Takizawa Laboratory (radioisotope waste treatment laboratory) neighboring Nishina Memorial Cyclotron Center for detection of radionuclide in those. We examine annual variations of elemental concentrations in two kinds of environmental samples (pine needle and grass) collected during 5-years period. These were prepared using nitric acid ashing method and analyzed using ordinal vacuum PIXE for detection of the elemental concentration. The result indicates that the concentrations of potassium and phosphorous in grass change according as fertilizer. This is the primary study. The results of annual variations of elemental concentrations in other environmental samples will be described in another paper in the near future.

Determination of detection efficiency curves of HPGe detectors on radioactivity measurement of volume samples

An efficiency calibration method has been developed to measure radioactivity of volume samples with HPGe detectors. The method has two main procedures. One is a point-source calibration at a representative point near the detector. The position of the representative point is determined by Monte Carlo simulations. The other is correction for absorption by a sample matrix and a sample container. This paper presents application of the method for obtaining efficiency curves for volume samples in the energy range from 22 to 1836 keV. In addition to the standard volume sources of cement and water matrices, measurement was made with some kinds of environmental samples that are often used in environmental monitoring for radiation control works. The composition of the environmental sample was determined by elemental analysis. For these samples, measured absorption correction factors were compared with those by the Monte Carlo simulations. As a result, detection efficiency curves were obtained with good accuracy for variety types of volume samples.

Prediction of gas chromatographic retention indices of polychlorinated dibenzothiophenes on non-polar columns

Polychlorodibenzothiophenes (PCDTs) have been found in several kinds of environmental samples. The lack of reference compounds has meant that very little is known about their gas chromatographic behavior. Here we discuss the retention of 19 authentic PCDTs and their sulfones on the widely used gas chromatographic stationary phases DB-5 and DB-5ms. The retention order is different from that of the polychlorodibenzofurans. The data generated allowed us to carry out a multiple linear regression to generate parameters for predicting the retention indices of unknown congeners based only on their structural features.

Adaptation of a radioanalytical method for strontium-90 to different kinds of environmental samples and its application for the investigation of some samples in the Riyadh region

A relatively simple and rapid radioanalytical method, limited to milk, is adapted for investigating soil, biological and water samples for90Sr. The method is based on a selective separation and successive counting of equilibrium quantities of its daughter 90Y, which can be extracted by tributyl phosphate from nitrate medium and stripped by conc. ammonia solution. 90Y is separated from possible iron and measured by Cerenkov counting. The procedure is thoroughly tested with certified reference materials and used lately for determining90Sr in some environmental samples in the Riyadh region. The results obtained are given and discussed.

Activities related to environmental specimen banking in Japan

Some experiments on the preservability of chemicals in environmental samples such as atmospheric particulate matters and mussel meat have been conducted by National Institute for Environmental Studies (NIES), Japan, as a preliminary study for future establishment of environmental specimen bank. NIES also has been operating a small experimental sample bank, storing several kinds of environmental samples. Closely cooperating with NIES, Environment Agency of Japan has been performing several types of nationwide environmental monitoring of chemical substances and some parts of the collected samples have been stored in the cold storage room for future use. A retrospective analysis of TBT and TPT in the fish using these stored samples showed an availability and usefulness of specimen bank for the long term monitoring of pollutants.

Optimization of a radioanalytical procedure for the determination of uranium isotopes in environmental samples

A radiochemical procedure is described for the fast and sensitive measurement of uranium isotopes in gaseous and liquid effluents of nuclear facilities. Equally, this procedure is suitable to measure uranium isotopes in all kinds of environmental samples. Uranium is leached from ashed sample materials with HNO3, HF, and Al(NO3)3 solution and separated from matrix elements by extraction with trioctylphosphinic oxide and backextraction with NH4F. After radiochemical cleaning by coprecipitation with LaF3 and anion exchange, uranium isotopes are electroplated on stainless steel discs from HCl/oxalate solution. The preparation is measured by alpha-spectrometry using surface barrier detectors. The detection limit for 1000 minutes of counting time is 2 mBq per sample and nuclide, the chemical yield is in the range of 50 to 80%.

SIMPLE AND RAPID METHOD FOR DETERMINING TRACE AMOUNTS OF ENVIRONMENTAL CONTAMINANTS WITH DETECTOR TUBE SYSTEM

Detector tube, an integral-and-direct-reading method, was combined with operations such as trapping (absorption, absorption and filtration), aeration, redox reaction and pyrolyzing, and applied to more kinds of environmental samples and smaller amounts of contaminants in them than itself alone. The system for samples of exhaust gases, workers environments, atmosphere and river and waste waters, and the performance were described.

Characterization of fe bearing compounds in environmental samples

Using57Mossbauer spectroscopy and neutron activation analysis, various kinds of environmental samples have been studied, in order to demonstrate that the combination of a phase sensitive and a multi-element technique is a powerful tool for studying environmental problems.

Flow-through determination of sulphate in water using different methods: A comparison

Sulphate was determined in various kinds of environmental samples using a continuous-flow system, a flow-injection system or a flow-through titrimeter. The reagents in the three cases consisted basically of DMSA(III), KNO3 and Ba(ClO4)2. The results of the three methods were evaluated statistically. A comparison of the three methods is given. The advantage of the DSMA(III)-methods is shown in a comparison with the commonly used thorin method.