Analysis Of Pollutants In Water Research Articles

Continuous solid-phase extraction spectroscopy and its quantification method for trace analysis

This study designed and developed an innovative online detection device based on Continuous Solid-Phase Extraction Spectroscopy (CSPES) for rapid quantitative analysis of environmental water pollutants. The device is highly automated, eliminating environmental interference. Leveraging CSPES technology and adsorption kinetics theory, an online quantitative analysis model between the spectrum and component concentrations was established, along with a concentration calculation method based on the least squares method. The quantitative analysis method was validated using single-component and binary-component sample systems containing Fluoranthene, Benzo[k]Fluoranthene, and Rhodamine 6G. The model exhibited excellent predictive performance, with overall prediction concentration relative errors (RE) ranging from 0.45 % to 8.75 % and relative standard deviations (RSD) of less than 3 %. In real sample applications, recovery rates ranged from 86.8 % to 124.4 %, with RSDs between 0.33 % and 2.22 %. This method provides a robust tool for water quality monitoring and environmental analysis, holding significant potential for application across various fields.

Automated pretreatment of environmental water samples and non-targeted intelligent screening of organic compounds based on machine experiments

The complexity of environmental pollutants poses significant challenges for monitoring and analysis, especially with the emergence of numerous emerging contaminants. Traditional analysis methods rely mainly on laboratory analysis, which involves labor-intensive and time-consuming sample preparation procedures and non-target data analysis, greatly limiting the rapid detection of water organic pollutants. In this study, we designed a robot experimenter combined with GC × GC-TOFMS. By configuring self-developed automated analysis software, we established a fully automated process from sample collection to data characterization, for the analysis of organic pollutants. We validated the method with 111 organic standards compounds. The robot performed 2577 actions covering the entire workflow, from water sample collection to sample pre-treatment. The integration of mass spectrometry and related software enabled the automatic analysis of emerging hazardous contaminants, from sampling to the output of detection results. The results showed the automated process could qualitatively identify all compounds and demonstrated good linearity, low detection limits, and excellent quantitative ability within the range of 0.04–0.4 mg/L. The average recoveries of 82.89 % of the samples ranged from 70 % to 120 % (relative standard deviation (RSD) <15 %) at different spiked concentrations. This indicated that the established method could be used for non-targeted analysis of emerging contaminants in environmental water samples. We applied the method to samples from wastewater treatment plants and river sections, identifying 1,902 compounds across 26 categories, including 6 known hazardous contaminants found in all samples. The relative content of these characteristic compounds will inform whether treated wastewater meets discharge standards and aid in tracing the sources of pollutants. Therefore, the development of this fully automated machine experimental method enables real-time and online automatic analysis of organic pollutants in environmental water. The establishment of characteristic fingerprints can provide technical support for early warning and traceability of water quality.

STORET (Storage and Retrieval) method for analysis and identification of water pollutants in the Upper Citarum Watershed, West Java, Indonesia

Water pollution in the Citarum watershed is currently an urgent problem to control. Water pollution usually occurs due to the large number of pollutants entering the water bodies, such as from household, agricultural, industrial, livestock, and land use wastes. This study was conducted in the Citarum upstream watershed and divided into five locations: Situ Cisanti, Cikawao, Koyod, Rancamanyar, and Nanjung. This study aimed to analyze and identify the pollution level in the Citarum upstream watershed based on the BOD (biological oxygen demand), TDS (total dissolved solids), chloride, zinc, total detergent, nitrate, nitrite, lead, mercury, and phenol concentrations. These parameter data were then compared to the Indonesian government regulation for river water quality standards No. 22/2021 and the STORET (Storage and Retrieval) method, based on the United States Environmental Protection Agency (US EPA). Water sampling from each location was carried out in different seasons. The STORET value in the rainy season was categorized as slightly polluted with the value of -10, then became -34 in the dry season as heavily polluted. Therefore, water pollution management is necessary to sustain the water resources by controlling the domestic waste and fertilizer application in agriculture and livestock culture.

Comprehensive Analysis of the Association between Human Diseases and Water Pollutants

Drinking water is an important natural resource. For many people worldwide, especially in developing countries, access to safe drinking water is still a dream. An increasing number of human activities and industrialization have caused various physical, chemical, and biological pollutants to enter water bodies, affecting human health. Water pollutants contain a vast number of additives, such as perfluorinated chemicals, polybrominated diphenyl ethers, phthalate, nanomaterials, insecticides, microcystins, heavy metals, and pharmacologies. In this work, we aim to explore the potential relationship between water pollutants and human diseases. Here, we explored an integrative approach to identify genes, biological processes, molecular functions, and diseases linked to exposure to these water pollutants. These processes and functions affected by water pollutants are related to many diseases, including colonic neoplasms, breast neoplasms, hepatitis B, bladder cancer, and human cytomegalovirus infection. In addition, further analysis revealed the genes that play a key role in the human diseases induced by water pollutants. Therefore, conducting an integrative toxicogenomic analysis of water pollutants is more appropriate for evaluating the potential effects of water pollutants on human health.

Characteristics analysis of water pollutants in Cihu Lake, China, based on a multivariate statistical analysis method

In order to understand the sources of pollutants and the temporal and spatial distribution characteristics of the water quality in Cihu Lake, China, the monitoring data of seven water quality indicators from 12 sampling sites from 2015 to 2019 were selected, and the temporal and spatial variation laws of the water quality and pollution sources were analyzed by the use of the multivariate statistical analysis method. The results show that nitrogen and phosphorus pollution in the lake is dominant. The average concentrations of total nitrogen (TN) and total phosphorus (TP) exceed the surface water quality Class III standards by 1.6 and 2.2 times, respectively. Spatially, the results of the cluster analysis showed that the water quality in Cihu Lake can be categorized into three regions: the northern half of the lake, the southern half of the lake, and the canal entering the lake. Temporally, the water quality in these three regions can be classified into three categories: March to May (the northern half of Cihu Lake), September to November (the southern half of Cihu Lake), and September (the canal entering Cihu Lake). The discriminant analysis results showed that NH3-N, TN, CODCr, and BOD5 are the main factors that affect the uneven spatial distribution of the water quality of Cihu Lake, while TN, DO, and CODMn are the main factors that affect the temporal difference in the northern half of Cihu Lake, and NH3-N, TP, CODCr, DO, CODMn, TN, and TP are the main factors affecting the temporal difference in the southern half of Cihu Lake and the canal entering Cihu Lake. It was found that the water pollution in the study area can be mainly attributed to the incoming water and urban domestic pollution. The main pollution sources for the canal entering Cihu Lake and the southern half of Cihu Lake are the water from the sewage treatment plant and the domestic sewage that has not been intercepted, while the northern half of Cihu Lake is mainly affected by surface runoff, mixed rainwater and sewage, and internal pollution.

A Portable Microfluidic-Based Electrochemiluminescence Sensor for Trace Detection of Trenbolone in Natural Water.

In this study, a portable electrochemiluminescence sensor chip was designed for trenbolone (TBE) trace detection in environmental water. First, a stable ECL signal was obtained with low-toxicity 3,4,9,10-perylenetetracarboxylic acid (PTCA) as a luminophore and persulfate (S2O82-) as a coreactant. Second, hollow-structured Cu2MoS4 was introduced as a coreaction accelerator to catalyze S2O82- reduction. The reversible conversion of the mixed-valence transition metal ions in Cu2MoS4 (Cu+/Cu2+ and Mo4+/Mo6+) greatly promoted the generation of the sulfate radical (SO4•-). Meanwhile, the special porous structure of Cu2MoS4 possessed a large specific surface area, thus enhancing its catalytic performance. Based on these enhancement mechanisms, a strong ECL signal was acquired, which improved the detection sensitivity of the constructed sensor. Importantly, a microfluidic chip was introduced for sensing detection, thereby improving the practicality of the sensor. The developed sensor chip was miniature and portable, exhibiting high sensitivity for TBE detection with a wide linear range (10 fg/mL-100 ng/mL) and lower detection limit (3.32 fg/mL). This was of great significance for timely and rapid analysis of steroid pollutants in natural water.

Compound specific stable carbon isotope analysis of aromatic organic contaminants in water using gas chromatography coupled to mid-infrared laser spectroscopy

A mid-infrared laser based analytical approach is newly developed in this study for gas chromatography (GC) separation and carbon compound specific isotope analysis (CSIA) of aromatic organic pollutants in water.

Study, analysis and detection of pollutants in rain water for selected areas over Baghdad city for the 2018-2019 rainy season

Some clouds result in rain, such as cumulus clouds and cumulmbus clouds, as rain water is one of the important factors in purifying the air from plankton and impurities in air, Which also helps to soften and moisten the atmosphere, and because of the pollution that many countries of the world suffer from, and since the industrial revolutions that resulted in the rise of pollutants in the atmosphere, and the reason for this is the activity of factories that led to the rise of smoke and toxic gases, As well as car exhaust, generators, and environmental activities caused by dust storms, so the city of Baghdad was chosen to study and detect pollutants in rainwater, as samples of rainwater were collected from different areas including the center and outskirts of Baghdad for the 2018-2019 rainy season, and samples were analyzed by (xrf) technology., After examining the samples, it was found that there are different percentages of pollutants over each of these areas (the study area), as the results showed that the highest percentage of acidity (Ph) was in the Kemaliya area (7.5ppm) and the highest percentage of dissolved salts (46.1ppm) in the Shuala area, and the highest. The percentage of turbidity in the Abu Dashir area was (76ppm).

Continuous in situ portable SERS analysis of pollutants in water and air by a highly sensitive gold nanoparticle-decorated PVDF substrate.

The increasingly serious environmental pollution worldwide has posed a great threat to the ecosystem and human health, and yet the development of portable in situ monitoring techniques that are sensitive to gaseous and water pollutants remains incomplete. Herein, we report a highly active surface-enhanced Raman spectroscopy (SERS) substrate fabricated by immobilizing gold nanoparticles (AuNPs) onto a polyvinylidene fluoride (PVDF) membrane for continuous in situ SERS detection of pollutants in water and atmosphere. 4-Mercaptobenzoic acid (4-MBA) was adopted as a probe molecule to evaluate the performance of the substrate, and the results indicate that the polymer-based flexible substrate features high sensitivity, uniformity, and repeatability. The fabricated PVDF/SERS substrate was integrated with a portable Raman spectrometer operating under both passing-by and passing-through modes. The integrated system accomplishes quantitative detection and real-time online monitoring of pH in a liquid environment with a response speed of less than 10s and the rapid SERS response to gas molecules at a low concentration within 30s. We also demonstrated the highly sensitive detection for mainstream smoke (MS) and sidestream (SS) of cigarette smoke and verified their differences in the main constituent which contributes to the harmful secondhand smoke in public. The developed portable Raman system has excellent application prospects in online liquid and gas environmental detection.

Colloidal dendritic nanostructures of gold and silver for SERS analysis of water pollutants

Surface-Enhanced Raman Scattering (SERS) using colloidal metal (Ag, Au) nanoparticles has been regarded as a powerful method for detecting organic pollutants at vestigial levels. Although less investigated, the controlled synthesis of binary nanostructures comprising two metals provides an alternative route to SERS platforms with tuned surface plasmon resonances. Here, we demonstrate that the use of dendrimers allows the formation of distinct combinations of Ag:Au nanostructures that are composed of smaller metal nanocrystals. Our research highlights the role of the dendrimer macromolecules as a multipurpose ligand in the generation of such hybrid nanostructure, including as a reducing agent, an effective long-term colloidal stabilizer and as a molecular glue for interconnecting the primary metal nanocrystals. Noteworthy, the dendrimer-based Ag:Au hybrid nanostructures are more SERS sensitive as compared to the corresponding colloidal blends or to the single-phase metals, as revealed by using molecular pesticides as analytes in spiked water samples. We suggest that the high SERS sensitivity of the hybrid nanostructures is due to interparticle plasmonic coupling occurring between the primary metal nanoparticle aggregates, whose arrangement is templated by the presence of the dendrimer macromolecules.

Investigation of silver decorated silicon nanowires as ultrasensitive and cost-effective surface-enhanced Raman substrate

Quantitative analysis of organic pollutants in water and soil is an important issue for the ecological environment and human health. Surface-enhanced Raman spectroscopy (SERS) is a powerful detection technique. Silicon nanostructures are getting more attention due to low-cost fabrication and high enhancement factors for SERS. To detect organic pollutants, silicon nanowires (SiNWs) are fabricated here by metal-assisted chemical etching and silver nanoparticles are deposited by the electroless method. As the length of SiNWs is increased, the enhancement of SERS is decreased. In this work, a systematic study is conducted to discriminate closely related molecules in the tertiary mixture. When the mixture of Rhodamine 6G, Malachite green and Methylene blue) solutions are taken in the ratio (1:1:1), mostly Rhodamine 6G dye is detected in the Raman spectra. When this ratio is changed to (1:2:2), Raman modes of all other dyes are distinguished easily. It emphasizes the importance of research in the area of separation and detection of organic dyes with the help of SERS.

Dispersive Liquid-Liquid Microextraction Combined with Microwave Demulsification for Determination of FAME Residuals in Biodiesel Wastewater.

Biodiesel consists of various fatty acid methyl esters (FAMEs) that are mainly produced through transesterification of plant oil or animal fat. It is essential for biodiesel to be purified utmostly to meet its product standard before being traded, while the universal purification method has been water washing. However, water washing inevitably causes the residual of FAMEs in wastewater, which represents a loss of industrial profits. For the purpose of determination and monitoring of the FAME profile in wastewater, there is a necessity to develop a fast and reliable approach with small volume of sample in need. Hence, in this study, a combination of dispersive liquid-liquid microextraction (DLLME) and microwave demulsification is applied for the enrichment of residual FAMEs in water, followed by qualitative and quantitative analyses using gas chromatography-mass spectrometry. The results indicate that the optimal extractant in DLLME approach is toluene. And the optimal parameters are 20mL of water sample, 80μL of toluene as the extractant, 60s of ultrasonic irradiation duration, 200W of microwave power and 2min of microwave irradiation duration. The standard curves and linear equations obtained with these conditions are used for the quantitative analysis of biodiesel wastewater, which reveals that there was 50.35mg·L-1 of the total FAME residuals in wastewater. To the best of our knowledge, it is for the first time that the combined technique of DLLME and microwave demulsification is applied in determination of residual FAMEs in water samples. The proposed method corresponds to small volumes of sample and extractant and short analytical period. It also has the potential to be extended to the analysis of other water pollutants.

Analysis and Risk Assessment of Organic Pollutants in Surface Water from Xujiahe Basin, China

In this study, organic compounds were screened in surface water collected from Xujiahe basin, China by gas chromatography-mass spectrometry (GC-MS). A total of 51 compounds were identified including 14 organochlorine pesticides (OCPs), 9 organophosphorus pesticides (OPs), 16 polycyclic aromatic hydrocarbons (PAHs) and 12 chlorobenzene (CBs). The concentrations of OCPs, PAHs and CBs were generally low. The concentrations of OCPs in Xujiahe reservoir ranged from N.D. to 35.6ng/L, the concentrations of PAHs ranged from N.D. to 19.8ng/L and the concentrations of CBs ranged from 10.3 to 124.6ng/L. The Ecological Structure Activity Relationships (ECOSAR) model was employed to directly predict the integrated toxicity indexes of 51 organic pollutants. The risk quotient (RQ) values of most of the organic compounds in the water samples were acceptable for their ecological risk.

Determination of Monoaromatic Hydrocarbons in Water Samples by Nano-Liquid Chromatography using a Composite Carbon Nanotubes- Lauryl Polymethacrylate Capillary Monolithic Column

Background: This work reports a green analytical method for the determination of organic environmental pollutants using nano-liquid chromatography with a self-made column for rapid, sensitive, inexpensive and efficient analysis of BTX pollutants in water. The applications of monolithic nanoscale columns for quantitative analysis of environmental real samples are very limited in the literature. Methods: A capillary column containing a composite of multi-walled carbon nanotubes incorporated into a lauryl methacrylate-co-ethylene dimethacrylate porous monolithic polymer was fabricated for the determination of BTX pollutants in real water samples. Results: Baseline separation was accomplished at 0.4 µL/min flow rate with UV-detection set at 208 nm. Under the optimum conditions, the calibration curves were validated over the range of 1.0-500 µg/L with R2 more than 0.9992. The detection limits of benzene, toluene, o-xylene and m/p-xylene were 0.25, 0.05, 0.075 and 0.05 µg/L, respectively. After a simple extraction process with a theoretical preconcentration factor equal to 200, the recovery values in Milli-Q, tap and sea water samples were found to be ranged from 84.85 to 97.84% with %RSD less than 7.5. Furthermore, we reported a comparison between our prepared composite column with a commercial C18 silica based column which is the most used in such analytical field. Each column demonstrated its advantages from different analytical aspects. Conclusion: The application of monolithic columns and nano-scale LC for routine analysis of environmental samples is very promising as the use of monolithic capillary columns offers several advantages over conventional scale particulate packed columns.

Application of solid-phase extraction based on magnetic nanoparticle adsorbents for the analysis of selected persistent organic pollutants in environmental water: A review of recent advances

Sample preconcentration is a critical step in the analysis of trace organic pollutants in environmental water. In recent years, solid-phase extraction based on functionalized magnetic nanoparticle (MNP) adsorbents has attracted wide attention because of its advantages in time, reagent, and labor savings, as well as its high extraction efficiency. To improve the selectivity, dispersibility, stability, and reusability of MNP adsorbents, various functional materials have been applied, including inorganic materials, carbonaceous materials, organic compounds, metal–organic frameworks, and bio-sorbents and their hybrid forms. Here, the application of solid-phase extraction based on MNP adsorbents for trace persistent organic pollutant (POP) detection in environment water from 2015 to 2019 is reviewed. In addition, the synthetic routes, characteristics of modification materials, selective sorption mechanisms, and analytical performance of these adsorbents are also discussed. The properties of environmental water samples have complicated effects on the extraction efficiency of POPs, and improvements in magnetic solid-phase extraction (MSPE) for POP analysis should be carried out with regard to the following four aspects: (1) development of novel applicable functionalized MNP adsorbents; (2) choice of suitable detection techniques; (3) combination of other extraction techniques; and (4) automation of MSPE.

Ultrasensitive SERS detection of rhodamine 6G and p-nitrophenol based on electrochemically roughened nano-Au film

Quantitative analysis of organic pollutants in environmental water is an important issue for ecological environment and human health. In this paper, the quantitative analysis of rhodamine 6G (R6G) and p-nitrophenol (PNP) is performed by the surface enhanced Raman scattering (SERS) technology. The enhancement of Raman signals is achieved on the surface of an electrochemically roughened nano-Au film. The SERS performance depends on the microstructure of roughened nano-Au films, which is affected by the thickness of Au films and electrochemical roughening parameters. The structure-dependence of SERS performance is validated by finite element simulation of local electromagnetic field distribution. An obvious SERS effect of R6G with an enhancement factor of 108 is obtained on the roughened nano-Au film. A sensitive SERS detection of R6G with a linear range of 10−9-10−5 M and a detection limit of 10−11 M is realized. Moreover, a wide linear range of 10−9-10−3 M is obtained for the detection of PNP. The roughened nano-Au film is an effective substrate for the SERS detection of organic pollutants with high reproducibility and good stability. Therefore, the electrochemical technology in this study is expected to be a very promising method for the fabrication of high-performance SERS substrate.

Carbon Paste Modified Electrode as Powerful Sensor Approach Determination of Food Contaminants, Drug Ingredients, and Environmental Pollutants: A Review

Background:Application of electrochemical sensors for analysis of food, biological and water polluting compounds helps to speed up their analysis in the real samples. Electrochemical sensors with low cost, fast response and portable ability are a better choice compared to traditional methods for analysis of electro-active compounds such as HPLC. Therefore, in recent years, many analytical scientists have suggested this type of analytical method for analysis of food, biological compounds and water pollutants.Objective:Due to low cost, easy modification and low non-faradic current, the carbon paste electrode is a suitable choice as a working electrode in the electrochemical and especially voltammetric analysis. On the other hand, modification of carbon paste electrode can improve the quality of the sensor for the analysis of electroactive compounds at nanomolar level.

Analysis of volatile organic compounds in environmental matrices by nitrogen-assisted headspace solid-phase extraction

A novel pretreatment method named nitrogen-assisted headspace solid-phase extraction (NA/HS-SPE) was developed for the analysis of volatile organic pollutants in water, sediment, honey, and juice.

Direct speciation analysis of organophosphorus environmental pollutants in water by HPLC-ICPMS/MS

A new and optimized HPLC-ICPMS/MS method for the simultaneous determination of five of the most common phosphorous environmental pollutants in various water matrices has been developed, including aminomethylphosphonic acid (AMPA), glufosinate, glyphosate, fosamine, and ethephon. We show that the ICPMS/MS confers an average of 20-fold improvement in the detection limit (0.1–0.3 µg P L−1) relative to comparable methods based on single quadrupole ICPMS detection, without the incorporation of any sample purification or preconcentration step. The method was validated by determining the intra-day repeatability (< 6%), inter-day repeatability (< 10%) and recovery (86–112%) of 4 levels of spiking (5.0–250 µg L−1). The developed method involved utilizing the carbon enhancement effect which yielded up to 3-fold increase in sensitivity. A signal suppression effect exerted by the carbonate content of the analyzed water samples was identified, and should be generally taken into consideration when analyzing untreated hard water samples by HPLC-ICPMS. The developed method can be an important contribution in order to keep up with increasingly more stringent future regulations for the levels of the analyzed pollutants given their rising health concerns.

An in-source helical membrane inlet single photon ionization time-of-flight mass spectrometer for automatic monitoring of trace VOCs in water

An in-source, helical membrane inlet single photon ionization time-of-flight mass spectrometry (SPI-TOFMS) has been developed to improve the detection sensitivity of trace volatile organic compounds (VOCs) in water. A helical winding membrane and a four-stage differential pumping system of TOFMS was designed to improve and maintain the vapor pressure of analyte, which is linearly associated with the sensitivity of SPI. The helical winding increased the length of the hollow fiber membrane (HFM) from 7 cm to 100 cm and the pressure inside of SPI source was elevated from 3.6 Pa to 28 Pa, and then the sensitivity was increased by 16, 34.7, 32.3, 17.9 and 13.9 times for benzene, ethyl tert-butyl ether (ETBE), aniline, p-xylene, and chlorobenzene (MCBz) respectively. The limits of quantitation (LOQs) of benzene, ETBE, aniline, p-xylene and MCBz were 0.014, 0.143, 0.556, 0.036, 0.025 μg L−1 respectively with a measurement time of 50 s, which were enhanced by more than one order of magnitude compared to our previous work (reference [32]). The in-source design of helical winding membrane i.e. putting the membrane inside the SPI source dramatically reduced the response time to 1.33 min. This system has been evaluated for VOCs in sewage water of different laboratory buildings and automatic monitoring the pollutants in sewage water from a biological laboratory building. The automatic continuous analysis of organic pollutants in water has very important significance and broad application prospect for online assessment of water quality.