Monkeypox Virus in Wastewater Samples from Santiago Metropolitan Region, Chile.

Sewage surveillance provides useful epidemiologic and public health information on viral infections at the population level. We detected monkeypox virus DNA from sewage samples covering 85% of the population in Santiago Metropolitan Region Chile. We also isolated infective viruses from those samples. Wastewater surveillance could complement clinical surveillance for monkeypox virus.

Zirconium Nanoparticles Based Vortex Assisted Ligandless Dispersive Solid Phase Extraction for Trace Determination of Lead in Domestic Wastewater using Flame Atomic Absorption Spectrophotometry.

In this paper, a sensitive and simple zirconium nanoparticles (Zr-NPs) based vortex assisted ligandless dispersive solid phase extraction (VA-LDSPE) method was developed for the preconcentration of lead from wastewater samples for the determination by slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS). Zr-NPs were synthesized using zirconium (IV) chloride salt as a starting material through a simple reduction process with sodium borohydride, and used as selective adsorbent for the extraction of lead ions from aqueous medium. Single variant experiments were carried out for all optimizations of sorption/desorption steps including pH of solution, amount of nanoparticles, mixing type/period and eluent type. An SQT with five round slots was placed onto the burner of FAAS to increase the interaction between lead atoms and light from radiation source to enhance the absorbance signals. Under the determined optimum conditions, analytical figures of merit were evaluated and the limit of detection and quantification (LOD/LOQ) values were calculated as 5.2 and 17.3 µg L- 1, respectively. The developed method showed a linear calibration range between 25 and 250 µg L- 1 with a good regression coefficient value (0.9995). Recovery studies were also performed with domestic wastewater samples spiked at three concentrations and percent recovery values obtained in the range of 97%-102% validated the developed method's applicability and accuracy.

In-situ formation of Zn-Al layered double oxides on electrochemically anodized nanoporous aluminum film as sorbent for chlorophenols extraction from water and wastewater followed by determination using HPLC.

Herein, we present a simple, cost-effective, and robust strategy for the in-situ preparation of Zn-Al layered double oxides-anodized aluminum thin film via a facile hydrothermal method, followed by calcination treatment of the Zn-Al layered double hydroxide in the air atmosphere. The in-situ prepared Zn-Al layered double oxide-anodized aluminum film was implemented as sorbent for thin film microextraction of four selected chlorophenols (4-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, and pentachlorophenol), followed by high-performance liquid chromatography-ultraviolet detection. The different variables of the thin film microextraction were screened via Plackett-Burman design and then optimized through Box-Behnken design. Under the optimum condition, the method showed good linear ranges (0.2-200 µg/L) with the coefficient of determinations higher than 0.9938. The calculated limit of detections were between 0.07 and 0.56 µg/L. Relative standard deviations of the method for determination of the analytes at 5 µg/L concentration level (n = 3) were ranged from 3.5 to 3.9% (as interday). The enrichment factors were between 39 and 58. This extraction method was demonstrated to be fast, efficient, and convenient. To study the capability of the developed method for real sample analysis, tap, well, river, and two types of wastewater samples were satisfactorily analyzed.

Selective Fluorometric Analysis of Hg(II) in Industrial Waste Water Samples.

The highly selective and sensitive fluorometric method has been developed for trace level determination of Hg(II) is based on photo-induced electron transfer between rhodamine-6G dye and metal complex. Quenching in fluorescence intensity by fluorescence resonance energy transfer (FRET) is due to interaction between metal ion complex and dye. The fluorescence emitted was measured at 510 and 550 nm, for excitation and emission wavelengths respectively. Possible interferences present in water samples, which could affect the analytical response are studied and determined. The calibration graph was dynamically linear from 0.002 to 0.05 mgL-1 of Hg(II) with limit of detection 7 × 10-4 mgL-1 and limit of quantitation 1.9 × 10-3 mgL-1. The Stern-Volmer constant (KSV) calculated for the quenching of R-6G with Hg (II) was 8.47 Lmg-1 s-1 at optimized reaction conditions. The proposed FRET based fluorometric method was applied successfully in different industrial wastewater samples with satisfactory outcome.

Determination of 5-fluorocytosine, 5-fluorouracil, and 5-fluorouridine in hospital wastewater by liquid chromatography-mass spectrometry.

Chemotherapeutics are pharmaceutical compounds the occurrence of which in the environment is of growing concern because of the increase in treatments against cancer diseases. They can reach the aquatic ecosystems after passing through wastewater treatment plants without complete removal. One of the most frequently used chemotherapeutics is 5-fluorouracil which exhibits a strong cytostatic effect. In this paper, an analytical methodology was developed, validated, and applied to determine 5-fluorouracil, its precursor, 5-fluorocytosine, and its major active metabolite, 5-fluorouridine, in hospital wastewater samples. Due to the expected low concentrations after dilution and interferences present in such a complex matrix, a very selective and sensitive detection method is required. Moreover, an extraction method must be implemented prior to the determination in order to purify the sample extract and preconcentrate the target analytes at micrograms per liter concentration levels. Solid-phase extraction followed by liquid chromatography with tandem mass spectrometry was the combination of choice and all included parameters were studied. Under optimized conditions for wastewater samples analysis, recoveries from 63 to 108% were obtained, while intraday and interday relative standard deviations never exceeded 20 and 25%, respectively. Limits of detection between 61 and 620 ng/L were achieved. Finally, the optimized method was applied to samples from hospital wastewater effluents.

Efficient Low-Cost Procedure for Microextraction of Estrogen from Environmental Water Using Magnetic Ionic Liquids.

In this study, three magnetic ionic liquids (MILs) were investigated for extraction of four estrogens, i.e., estrone (E1), estradiol (E2), estriol (E3), and ethinylestradiol (EE2), from environmental water. The cation trihexyl(tetradecyl)phosphonium ([P66614]+), selected to confer hydrophobicity to the resulting MIL, was combined with tetrachloroferrate(III), ferricyanide, and dysprosium thiocyanate to yield ([P66614][FeCl4]), ([P66614]3[Fe(CN)6]), and ([P66614]5[Dy(SCN)8]), respectively. After evaluation of various strategies to develop a liquid-liquid microextraction technique based on synthesized MILs, we placed the MILs onto a magnetic stir bar and used them as extracting solvents. After extraction, the MIL-enriched phase was dissolved in methanol and injected into an HPLC-UV for qualitative and quantitative analysis. An experimental design was used to simultaneously evaluate the effect of select variables and optimization of extraction conditions to maximize the recovery of the analytes. Under optimum conditions, limits of detection were in the range of 0.2 (for E3 and E2) and 0.5 µg L-1 (for E1), and calibration curves exhibited linearity in the range of 1-1000 µg L-1 with correlation coefficients higher than 0.998. The percent relative standard deviation (RSD) was below 5.0%. Finally, this method was used to determine concentration of estrogens in real lake and sewage water samples.

Antipsychotic drugs in hospital wastewater and a preliminary risk assessment.

The residues of pharmaceutical and personal care products are the cause of increasing concern around the world. The aim of this study was to carry out the quantification of six antipsychotic drugs in hospital wastewater with the aid of liquid chromatography-mass spectrometry and, subsequently, make a preliminary assessment of the environmental risk posed. Dispersive liquid-liquid microextraction and solid phase extraction were optimized by multivariate design and validated in compliance with international guidelines. The extraction procedures were successfully applied to the quantification of the six selected antipsychotics in samples that were formed each day and collected at two main sampling points of the sewage network over the period of a week, in December 2017. Olanzapine (0.31─0.52 µg L-1), clozapine (0.56─0.97 µg L-1), haloperidol (1.43─2.73 µg L-1), risperidone (0.92─0.98 µg L-1) and chlorpromazine (0.52 µg L-1) were found in at least one sampling point. In the case of most analytes, the highest concentrations were determined at sampling point A, which are derived from the psychiatric wing. The environmental risk quotient for clozapine, chlorpromazine and risperidone was ˃600, a very high-risk index, which signals the need for a better control of the emission of antipsychotics and an improvement of the wastewater treatment, especially, with regard to wastewater discharged from the hospital psychiatric wing.

Preconcentration of mercury(II) using a magnetite@carbon/dithizone nanocomposite, and its quantification by anodic stripping voltammetry.

A new adsorbent is described that consists of a magnetite@carbon/dithizone nanocomposite. It was characterized using energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and field emission scanning electron microscopy. The magnetic sorbent is shown to be a viable material for the preconcentration of mercury(II) before its quantification by differential pulse anodic stripping voltammetry. The effects of pH value, eluent, adsorbent amount, sample volume, and adsorption/desorption time were optimized. The calibration plot extends from 0.25 to 30 ng.mL-1, and the detection limit is 27 pg.mL-1. The preconcentration factor and intra-day and inter-day relative standard deviations are 100, 3.8, and 4.5%, respectively, for six measurements at 5 ng.mL-1 concentrations of mercury(II). The method was validated by the analysis of the certified reference material NIST SRM 1566b, and successfully applied to the preconcentration and quantification of mercury(II) in industrial wastewaters and spiked water samples. Graphical abstractSchematic representation of magnetic solid-phase extraction of mercury(II) ion by dithizone-modified Fe3O4@C nanocomposite (Fe3O4@C/Dz NC) before its quantification by anodic stripping voltammetry (ASV).

Determination of four acidic nonsteroidal anti-inflammatory drugs in wastewater samples by dispersive liquid-liquid microextraction based on solidification of floating organic droplet and high-performance liquid chromatography.

A simple, environmentally friendly, and sensitive dispersive liquid-liquid microextraction based on solidification of floating organic droplet for the extraction of four acidic nonsteroidal anti-inflammatory drugs (ketoprofen, naproxen, ibuprofen, and diclofenac) from wastewater samples subsequent by high-performance liquid chromatography analysis was developed. The influence of extraction parameters such as pH, the effect of solution ionic strength, type of extraction solvent, disperser solvent, and extraction solvent volume were studied. High enrichment factors (283-302) were obtained through the developed method. The method provides good linearity (r > 0.999) in a concentration range of 1-100 µg/L, good intra- and inter-day precision (relative standard deviation < 7%) and low limits of quantification. The relative recoveries of the selected compounds were situated over 80% both in synthetic and real water samples. The developed method has been successfully applied for the analysis of the selected compounds in wastewater samples.

Identification of environmental and methodological factors driving variability of Pepper Mild Mottle Virus (PMMoV) across three wastewater treatment plants in the City of Toronto.

PMMoV has been widely used to normalize the concentration of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA, influenza, and respiratory syncytial virus (RSV) to account for variations in the fecal content of wastewater. PMMoV is also used as an internal RNA recovery control for wastewater-based epidemiology (WBE) tests. While potentially useful for the interpretation of WBE data, previous studies have suggested that PMMoV concentration can be affected by various physico-chemical characteristics of wastewater. There is also the possibility that laboratory methods, particularly the variability in centrifugation steps to remove supernatant from pellets can cause PMMoV variability. The goal of this study is to improve our understanding of the main drivers of PMMoV variability by assessing the relationship between PMMoV concentration, the physico-chemical characteristics of wastewater, and the methodological approach for concentrating wastewater samples. We analyzed 24-hour composite wastewater samples collected from the influent stream of three wastewater treatment plants (WWTPs) located in the City of Toronto, Ontario, Canada. Samples were collected 3 to 5 times per week starting from the beginning of March 2021 to mid-July 2023. The influent flow rate was used to partition the data into wet and dry weather conditions. Physico-chemical characteristics (e.g., total suspended solids (TSS), biological oxygen demand (BOD), alkalinity, electrical conductivity (EC), and ammonia (NH3)) of the raw wastewater were measured, and PMMoV was quantified. Spatial and temporal variability of PMMoV was observed throughout the study period. PMMoV concentration was significantly higher during dry weather conditions. Multiple linear regression analysis demonstrates that the number and type of physico-chemical parameters that drive PMMoV variability are site-specific, but overall BOD and alkalinity were the most important predictors. Differences in PMMoV concentration for a single WWTP between two different laboratory methods, along with a weak correlation between pellet mass and TSS using one method may indicate that differences in sample concentration and subjective subsampling bias could alter viral recovery and introduce variability to the data.

Temporal Analysis of Pharmaceuticals as Emerging Contaminants in Surface Water and Wastewater Samples: A Case Study.

Pharmaceuticals in the environment are a global concern, with studies in all continents highlighting their widespread occurrence and potential ecological impacts, revealing their presence, fate, and associated risks in aquatic ecosystems. Despite typically occurring at low concentrations (ranging from ng/L to µg/L), advancements in analytical methods and more sensitive equipment have enabled the detection of a higher number of pharmaceuticals. In this study, surface and wastewater samples were extracted using solid phase extraction and analyzed using ultra-high-performance liquid chromatography with tandem mass spectrometry. Among the therapeutic classes investigated, nonsteroidal anti-inflammatory drugs/analgesics, antibiotics, and psychiatric drugs showed a higher number of detected pharmaceuticals. Concentrations ranged from below method detection limit (

Occurrence and removal of psychiatric pharmaceuticals in the Tehran South Municipal Wastewater Treatment Plant.

Psychiatric drugs released by humans in wastewater have received more attention because of their potential risks for aquatic organisms. In this study, the occurrence of the two most common groups of psychiatric drugs (sedatives-hypnotics-anxiolytics and antidepressants) were evaluated in the Tehran South Municipal Wastewater Treatment Plant. All the target sedatives-hypnotics-anxiolytics (alprazolam, phenobarbital, and thioridazine) and antidepressants (fluoxetine, citalopram, sertraline, and venlafaxine) were observed in influent and secondary clarification (SC) effluent. Thioridazine (164.25 ± 218.74 ng/L) and citalopram (672.53 ± 938.56 ng/L) had the highest mean concentrations in the influent, while alprazolam (5.09 ± 2.33 ng/L) and citalopram (776.97 ± 1088.01 ng/L) had the highest concentrations in the SC effluent. The higher concentrations of the psychiatric drugs, except thioridazine, were detected in the SC effluent compared to the concentrations in the influent. The increased drugs concentrations, with negative removal efficiencies, were more distinctive in the cold season samples. Psychiatric drugs processed in the chlorination unit followed a completely different pattern compared to the drugs in the biological treatment unit. All the drugs' concentrations, except thioridazine, decreased in the chlorination unit, ranging between 27 ± 14% for alprazolam and 75 ± 10% for citalopram. However, the mean concentrations of the detected drugs were as follows: sertraline (11.96 ± 11.62 ng/L) and venlafaxine (184.94 ± 219.74 ng/L) which could cause environmental and ecological concerns.

Short-term stability of wastewater samples for storage and shipment in the context of the EU Sewage Sentinel System for SARS-CoV-2.

In the context of an EU-wide surveillance system for SARS-CoV-2 in wastewater, recommended by the European Commission, this study aims to provide scientific support to the adequacy of transport and storage conditions of samples both in terms of duration and samples temperature. Three laboratories in Slovenia, Cyprus and Estonia investigated the short-term, one-week, isochronous stability of wastewater samples by RT-qPCR based detection of SARS-CoV-2 genes. The results were tested for statistical significance to determine uncertainty of quantification and shelf-life, at testing temperatures of + 20 °C and - 20 °C, relative to reference at + 4 °C. Samples were collected from three urban wastewater treatment plant influents and analysed respectively for SARS-CoV-2 genes N1, N2 (Laboratory 1), N2, E (Laboratory 2) and N3 (Laboratory 3), with various analytical methods. For a period of 7/8 days at + 20 °C, decreasing trends of measured concentrations were observed for all genes resulting in instability according to the statistical analysis, while at - 20 °C the trend of variation was stable only for N1, N2 (Laboratory 1) and N3 (Laboratory 3). Trends for gene E concentrations at - 20 °C (Laboratory 2) could not be tested statistically for stability because of lack of data. Over a period of just 3 days at + 20 °C, the variation was statistically non-significant indicating stability for genes N1, E and N3 for laboratories 1, 2 and 3, respectively. Nonetheless, the outcome of the study presents evidence to support the choice of the selected temperature at which samples shall be preserved during storage before analysis or transport to the laboratory. The conditions (+4 °C, ∼ few days) chosen for EU wastewater surveillance are in accordance with these results, highlighting the importance of stability testing of environmental samples to determine the short-term analytical uncertainty.

A 30-day follow-up study on the prevalence of SARS-COV-2 genetic markers in wastewater from the residence of COVID-19 patient and comparison with clinical positivity.

Wastewater based epidemiology (WBE) is an important tool to fight against COVID-19 as it provides insights into the health status of the targeted population from a small single house to a large municipality in a cost-effective, rapid, and non-invasive way. The implementation of wastewater based surveillance (WBS) could reduce the burden on the public health system, management of pandemics, help to make informed decisions, and protect public health. In this study, a house with COVID-19 patients was targeted for monitoring the prevalence of SARS-CoV-2 genetic markers in wastewater samples (WS) with clinical specimens (CS) for a period of 30 days. RT-qPCR technique was employed to target nonstructural (ORF1ab) and structural-nucleocapsid (N) protein genes of SARS-CoV-2, according to a validated experimental protocol. Physiological, environmental, and biological parameters were also measured following the American Public Health Association (APHA) standard protocols. SARS-CoV-2 viral shedding in wastewater peaked when the highest number of COVID-19 cases were clinically diagnosed. Throughout the study period, 7450 to 23,000 gene copies/1000 mL were detected, where we identified 47 % (57/120) positive samples from WS and 35 % (128/360) from CS. When the COVID-19 patient number was the lowest (2), the highest CT value (39.4; i.e., lowest copy number) was identified from WS. On the other hand, when the COVID-19 patients were the highest (6), the lowest CT value (25.2 i.e., highest copy numbers) was obtained from WS. An advance signal of increased SARS-CoV-2 viral load from the COVID-19 patient was found in WS earlier than in the CS. Using customized primer sets in a traditional PCR approach, we confirmed that all SARS-CoV-2 variants identified in both CS and WS were Delta variants (B.1.617.2). To our knowledge, this is the first follow-up study to determine a temporal relationship between COVID-19 patients and their discharge of SARS-CoV-2 RNA genetic markers in wastewater from a single house including all family members for clinical sampling from a developing country (Bangladesh), where a proper sewage system is lacking. The salient findings of the study indicate that monitoring the genetic markers of the SARS-CoV-2 virus in wastewater could identify COVID-19 cases, which reduces the burden on the public health system during COVID-19 pandemics.

Template-directed synthesis of zeolitic imidazolate framework-8 derived Zn-Al layered double oxides decorated on the electrochemically anodized nanoporous aluminum substrate for thin film microextraction of chlorophenols followed by determination with high-performance liquid chromatography.

In this work, hierarchical ZIF-8 coated anodized aluminum foil was prepared through in situ template-directed method without addition of any zinc salt. The hierarchical sorbent was synthesized by the formation of the final HZIF-8 on the previously created layered double oxide (LDO) template. The LDO template was created by calcining the firstly in situ prepared desired layered double hydroxide (LDH) precursor coated on the electrochemically anodized porous Al foil in an air atmosphere. The microextraction ability of the extracting device was studied through direct immersion thin film microextraction (DI-TFME). The extracted analytes were quantified by high-performance liquid chromatography equipped by UV detector (HPLC-UV). The present strategy was used for the simultaneous extraction and quantification of four selected chlorophenols (CPs) (as model analyte). The variables of the TFME were optimized using response surface methodology (Plackett-Burman and Box-Behnken design). Under the obtained optimum condition, the prepared film presented acceptable extraction properties including low limits of detection (0.03-0.22 µgL-1), good linear ranges (0.2-200 µgL-1, r2 > 0.9918) and satisfactory reproducibility (relative standard deviation, 3.6 < RSD < 5.8% for one film as inter- and intra-day RSD, 4.8 < RSD < 5.3% for film to film). Moreover, the obtained enrichment factors were in the range of 56-76. The kinetics and adsorption isotherm of the selected analytes adsorption to the prepared sorbent were also investigated. The maximum adsorption capacities of the selected analytes on the prepared sorbent were in the range of 26.4-80.1 mg g-1. The adsorption isotherm obeyed the Langmuir and Freundlich models. Moreover, the adsorption of the selected chlorophenols on the prepared film followed the pseudo-second-order kinetic model. Finally, the HZIF-8 film was utilized for the quantification of selected CPs in different types of water and wastewater samples. The results showed satisfactory relative recoveries (93-102%) and acceptable precisions (3.6 < RSD < 9.2%).

Evaluation of poly(ethylene diamine-trimesoyl chloride)-modified diatomite as efficient adsorbent for removal of rhodamine B from wastewater samples.

Diatomite (D) as a low-cost and eco-friendly clay was modified by ethylene diamine (EDA)-trimesoyl chloride (TMC) polymer to achieve a novel adsorbent for efficient removal of rhodamine B dye (RB) from wastewater samples. The EDA-TMC polymer was grafted to the surface of diatomite by in situ interfacial polymerization. The prepared p(EDA-TMC)/D adsorbent was characterized by XRD, FTIR, and SEM/EDX techniques. The effective experimental parameters on the adsorption performance were optimized with factorial design analysis. The equilibrium data were better correlated by non-linear Langmuir model compared to non-linear Freundlich model. The Langmuir monolayer adsorption capacity of the p(EDA-TMC)/D adsorbent was determined as 371.8 mg g-1. The key adsorption parameters were optimized by experimental design analysis. The kinetic findings showed the adsorption mechanism of RB onto p(EDA-TMC)/D adsorbent was well designated by the pseudo-second-order kinetic model. The thermodynamic results indicate that the RB adsorption had an exothermic character in thermal nature and was less favorable with increasing temperature from 20 to 60 °C. Furthermore, the adsorption/desorption yield of p(EDA-TMC)/D was still 80%/70% after 5th cycle and reduced to 60%/52% at the end of 8th cycle. Thus, the present study revealed that the developed p(EDA-TMC)/D composite had great adsorption potential for removal of RB from wastewater samples compared to that of different kinds of adsorbents reported in the literature.

Surveillance of Noroviruses in Rio De Janeiro, Brazil: Occurrence of New GIV Genotype in Clinical and Wastewater Samples.

Genogroup (G) IV norovirus (NoV) has been described in the literature as infectious agents in humans, although there are few reports regarding the frequency and spread of this virus, resulting in insufficient epidemiological data. The aim of this study was to investigate the occurrence of GIV norovirus in the State of Rio de Janeiro, Brazil in order to evaluate frequency, concentration, and genetic diversity using clinical and environmental approaches. For this purpose, 316 stool samples were collected from acute gastroenteritis cases reported over a period of three years. Wastewater samples were also obtained from the main wastewater treatment plant (WWTP) located in Rio de Janeiro throughout one year, totalizing 156 samples. All samples were submitted to quantitative analysis by TaqMan™ real-time PCR for GIV norovirus. Three out of 316 clinical samples were positive (0.9%) for GIV, with viral load ranging from 104 to 106 genome copies (CG) per gram. Regarding wastewater samples, GIV were detected in 52% of raw sewage, with viral load ranging from 104 to 106 CG per liter. Phylogenetic analysis revealed the circulation of a new GIV genotype in both clinical and environmental samples. To our knowledge, this is the first description of GIV norovirus in clinical samples in Brazil. These results demonstrate the importance of performing laboratory surveillance of clinical and environmental samples, assisting the comprehension of the epidemiology pattern of viruses with neglected diagnosis and indefinite impact in the population.

Magnetic ethylene diamine-functionalized graphene oxide as novel sorbent for removal of lead and cadmium ions from wastewater samples.

In this paper, magnetic ethylene diamine-functionalized graphene oxide (MDFGO) as a novel sorbent was synthesized and applied for removal of Pb(II) and Cd(II) from real wastewater samples. The morphology and molecular structure of MDFGO were studied by different analytical methods. The effective parameters in adsorption efficiency of Pb(II) and Cd(II) were studied and optimized using experimental design. Under the optimal condition, the effective parameters including pH, sorbent dosage, shaking rate, and adsorption time were 6.2, 33.0 mg, 500 rpm, and 11 min, respectively. Mechanism of adsorption kinetic was investigated using the Lagergren pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. It was found that adsorption of lead and cadmium ions in the MDFGO sorbent followed from pseudo-first-order and pseudo-second-order models, respectively. Thermodynamic parameters (ΔG°, ΔH°, and ΔS°) for the lead and cadmium ions uptake onto the MDFGO sorbent were calculated and indicated that the adsorption processes were spontaneous and endothermic in nature for both cations. In order to investigate the isotherm model for adsorption of Pb(II) and Cd(II), the experimental data were studied using the Langmuir, Freundlich, and Harkins-Jura isotherm models. The results fitted well with Freundlich model for both metal ions. The new sorbent (MDFGO) was applied to remove Pb(II) and Cd(II) from battery wastewater and electroplating wastewater. The removal percentage of Pb(II) and Cd(II) were 99.6±0.5 and 99.4±0.6, respectively, and demonstrated that the new sorbent was very suitable for removal of lead and cadmium ion from the real wastewater samples.

An alternative perspective of hollow fiber-mediated extraction: Bundled hollow fiber array-liquid-phase microextraction with sonication-assisted desorption and liquid chromatography-tandem mass spectrometry for determination of estrogens in aqueous matrices.

A bundled hollow fiber array (BHF)-liquid-phase microextraction (LPME) approach has been developed for the ultra-high performance liquid chromatography tandem mass spectrometric determination of estrone, 17ß-estradiol, estriol, and 17α-ethinylestradiol. The BHF was dipped in n-octanol to impregnate only the wall pores of the hollow fibers without deliberate loading of extractant solvent in the lumens, before placing it in the sample for extraction. Parameters influencing extraction efficiency, such as number of bundled hollow fibers, type of extraction and desorption solvent, agitation mode, extraction temperature and duration, and the salting out effect were examined. Under the most favourable experimental conditions, the enrichment factors were between 77 and 137-fold for the target compounds. The developed method offered high sensitivity and reproducibility. Low limits of detection and limits of quantification were achieved, i.e., between 0.251 and 0.440ng/L, and 0.995 and 1.82ng/L, respectively. Good intra and inter-day precision were obtained with relative standard deviations (RSDs) of less than 9%. BHF-LPME provided a new perspective on using membrane solvent-supported hollow fiber-mediated LPME. Raman spectroscopy was also introduced in this study to reaffirm that the polypropylene BHF did not play any role in the extraction; only the solvent was responsible.

Separation and identification of hormone-active compounds using a combination of chromatographic separation and yeast-based reporter assay.

Arxula adeninivorans-based yeast cell assays for the detection of steroid hormones demonstrated their efficiency for the determination of total hormone activity in a variety of samples using a microtiter plate format. In this study, a preliminary chromatographic separation using thin-layer chromatography plates is introduced in order to allow a rapid identification of the compounds responsible for this hormonal activity. The yeast whole cell assay can then be performed on the plate, producing a detectable signal where a steroid hormone is present. Simultaneous detection of estrogens, progestogens and androgens on the same plate in the picogram range was achieved, while keeping the assay as simple and affordable as possible. The assay requires a single incubation of the thin-layer chromatography plate and the detection of reporter protein production can be performed by fluorescence scanning of the plate at different wavelengths. The chromatographic separation allows the separation of several estrogens, androgens and progestogens, thus making its application for 'real world' samples very useful. In this work, different water-based samples from environmental origins were used to demonstrate the capacity of this new bioassay. Trials showed that most samples, with the exception of complex samples such as wastewater influent, can be assayed.