Repurposing spent filter sand from iron and manganese removal systems as an adsorbent for treating arsenic contaminated drinking water.

Waterworks which utilise river bank filtration water sources often have to apply aeration and sand filtration to remove iron and manganese during the drinking water treatment process. After some time, the sand becomes saturated and the spent filter sand (SFS) must be disposed of and replaced. In order to valorize this waste stream, this paper investigates the reuse of SFS as an adsorbent for the treatment of arsenic contaminated drinking water. The arsenic removal performance of SFS is compared with two synthetic iron oxide coated sands (IOCS). The sorbents were first characterized by SEM, EDS, BET specific surface area, and point of zero charge (pHpzc) measurements, and then investigated under a variety of conditions. The surface of the SFS was revealed to be coated with iron manganese binary oxide. The Freundlich model best described the isotherm experiment data, indicating a non monolayer adsorption model for arsenic adsorption on the three IOCS investigated. As(III) and As(V) removals were negatively effected by the presence of PO43- and HA anions as they competed with the arsenic species for adsorption sites. However, given the status of SFS as a waste material, the results obtained in this paper suggest it may be successfully reused as a very economically and environmentally sustainable solution for small waterworks requiring both As(V) and As(III) removal during drinking water treatment.

A Metabolomics approach for the diagnosis Of SecondAry InfeCtions in COVID-19 (MOSAIC): a study protocol.

BACKGROUND: Critically ill patients with COVID-19 are at an increased risk of developing secondary bacterial infections. These are both difficult to diagnose and are associated with an increased mortality. Metabolomics may aid clinicians in diagnosing secondary bacterial infections in COVID-19 through identification and quantification of disease specific biomarkers, with the aim of identifying underlying causative microorganisms and directing antimicrobial therapy. METHODS: This is a multi-centre prospective diagnostic observational study. Patients with COVID-19 will be recruited from critical care units in three Scottish hospitals. Three serial blood samples will be taken from patients, and an additional sample taken if a patient shows clinical or microbiological evidence of secondary infection. Samples will be analysed using LC-MS and subjected to bioinformatic processing and statistical analysis to explore the metabolite changes associated with bacterial infections in COVID-19 patients. Comparisons of the data sets will be made with standard microbiological and biochemical methods of diagnosing infection. DISCUSSION: Metabolomics analyses may provide additional strategies for identifying secondary infections, which might permit faster initiation of specific tailored antimicrobial therapy to critically ill patients with COVID-19.

Propofol Target-Controlled Infusion in Emergency Department Sedation (ProTEDS): a multicentre, single-arm feasibility study.

BACKGROUND: Procedural sedation is a core skill of the emergency physician. Bolus administration of propofol is widely used in UK EDs. Titrated to an end point of sedation, it has a rapid effect but has been associated with adverse incidents. The use of a target-controlled infusion (TCI) of propofol is not routine but may reduce the incidence of adverse incidents.The primary aims of this single-arm feasibility study were patient satisfaction and to establish recruitment rates for a randomised controlled trial comparing propofol TCI to bolus administration. METHODS: Four EDs in Scotland, UK, participated. Patients aged 18-65 years, with anterior shoulder dislocation, weight ≥ 50kg, fasted ≥ 90 min were screened. Patients underwent reduction of their dislocated shoulder using TCI propofol. The primary end point was patient satisfaction recorded on a Visual Analogue Scale. RESULTS: Between 3 April 2017 and 31 December 2018, 25 patients were recruited with a recruitment rate of 20% for the 16-month recruitment window, with a temporary pause to allow amendment of drug dosage.Two patients were excluded. Twenty achieved adequate sedation, defined as a Modified Observer's Assessment of Alertness/Sedation Scale (OAA/S) 3. Successful reduction was achieved in all adequately sedated. Patient satisfaction was documented in 14 patients, mean±SD of 97±9 and time to sedation was 25±8 min. No adverse events were recorded using the Society of Intravenous Anaesthesia adverse event reporting tool. CONCLUSION: Propofol TCI was acceptable as a method of procedural sedation for patients. The lower than expected recruitment rates highlight the need for dedicated research support. TRIAL REGISTRATION NUMBER: NCT03442803.

Arsenic adsorption on Fe-Mn modified granular activated carbon (GAC-FeMn): batch and fixed-bed column studies.

Granular activated carbon (GAC) was modified with Fe-Mn binary oxide to produce a novel effective hybrid adsorbent (GAC-FeMn) for simultaneous removal of As(III) and As(V) from water. After characterization (including BET, SEM/EDS and XRD analyses) of the raw and modified GAC, FTIR analysis before and after As removal showed that ligand exchange was the major mechanism for As removal on GAC-FeMn. Sorption kinetics followed pseudo-second order kinetics for both As(III) and As(V) and were not controlled by intraparticle diffusion. Batch equilibrium experiments yielded adsorption capacities for As(III) and As(V) of 2.87 and 2.30 mg/g, and demonstrated that better sorption was achieved at low pH. Of the competitive anions investigated (PO43-, SiO32-, CO32-, SO42-, NO3-, Cl-), phosphate had the greatest negative effect on As(III) and As(V) adsorption. Three sorption/desorption cycles were conducted in continuous column tests with a real arsenic contaminated groundwater, with subsequent TCLP leaching tests confirming the stability of the spent sorbent. In the column tests, breakthrough curves were also obtained for phosphates, which were present at a relatively high concentration (1.33 mg/L) in the investigated groundwater. The phosphates limited the effective operational bed life of GAC-FeMn for arsenic removal. Nonetheless, the maximum arsenic adsorption capacities for GAC-FeMn obtained by the Thomas model during the three sorption cycles were high, ranging from 18.8 to 29.8 mg/g, demonstrating that even under high phosphate loads, with further process improvements, GAC-FeMn may provide an excellent solution for the economic removal of arsenic from real groundwaters.

Arginase overexpression and NADPH oxidase stimulation underlie impaired vasodilation induced by advanced glycation end products.

BACKGROUND: Advanced glycation endproducts (AGEs) play a major role in the development of many vascular complications that are mediated by endothelial dysfunction. The present work aimed to investigate the mechanism by which AGEs impair vasodilation. METHODS: The effect of AGEs on vasodilation induced by acetylcholine or D NONOate was examined by incubating isolated rat aortae with different AGEs concentrations. ACh-induced nitric oxide generation was assessed using the fluorescent probe diaminofluorecein (DAF-FM). The effect of AGEs on expression of mRNA for arginase 2, NADPH oxidase and endothelial nitric oxide synthase (eNOS) were determined by real-time PCR. RESULTS: One-hour in vitro incubation of rat aortae with AGEs impaired endothelial-dependent vasodilation produced by ACh, while increasing D NONOate-induced vasodilation. Preincubation of aortae with l-ornithine, an arginase 2-inhibitor, prevented the impairment effect induced by AGEs on endothelial-dependent vasodilation. Superoxide scavenging by tempol or NADPH oxidase inhibition by apocynin also blocked the effect of AGEs. AGEs decreased ACh-induced NO production and this was inhibited by both l-ornithine and apocynin. Furthermore, AGEs exposure increased arginase mRNA expression but decreased mRNA expression for eNOS in isolated rat aortae. CONCLUSION: The present results indicate that AGEs impairs endothelial-dependent vasodilation, and this effect is mediated via arginase overexpression and NADPH oxidase stimulation.

Cardioprotection by 6-gingerol in diabetic rats.

The current study was conducted to evaluate the effect of 6-gingerol (6G) on cardiac complications in streptozotocin (STZ)-induced diabetic (DM) rats. STZ-induced DM rats (single 50 mg/kg i.p. injection, 15 days prior to drug treatment) or time-matched controls were treated with 6G (75 mg/day route orally). After a further 8 weeks, blood was collected for biochemical analysis and 8-isoprostenol was measured in urine. Cardiac hemodynamics and ECG was assessed. 6G significantly attenuated the increased level of blood glucose in diabetic rats and improved cardiac hemodynamics in including RR interval, max dP/dt, min dP/dt and Tau. In addition, 6G alleviated the elevated ST segment, T amplitude and R amplitude with no significant effect on disturbed levels of adiponectin, TGF-ß or 8-isoprostenol induced by diabetes. The results showed that treatment with 6G has an ameliorative effect on cardiac dysfunction induced by diabetes. Which may be not related to its potential antioxidant effect.

Xanthine oxidase inhibition alleviates the cardiac complications of insulin resistance: effect on low grade inflammation and the angiotensin system.

BACKGROUND: We have previously shown that hyperuricemia plays an important role in the vascular complications of insulin resistance (IR). Here we investigated the effect of xanthine oxidase (XO) inhibition on the cardiac complications of IR. METHODS: IR was induced in rats by a high fructose high fat diet for 12 weeks. Allopurinol, a standard XO inhibitor, was administered in the last 4 weeks before cardiac hemodynamics and electrocardiography, serum glucose, insulin, tumor necrosis factor alpha (TNFα), 8-isoprostane, uric acid, lactate dehydrogenase (LDH) and XO activity were measured. Expression of cardiac angiotensin II (AngII) and angiotensin receptor 1 (AT1) were assessed by immunofluorescence. RESULTS: IR animals had significant hyperuricemia which was inhibited by allopurinol administration. IR was associated with impaired ventricular relaxation (reflected by a decreased diastolic pressure increment and prolonged diastolic duration) and XO inhibition greatly attenuated impaired relaxation. IR was accompanied by cardiac ischemia (reflected by increased QTc and T peak trend intervals) while XO inhibition alleviated the ECG abnormalities. When subjected to isoproterenol-induced ischemia, IR hearts were less resistant (reflected by larger ST height depression and higher LDH level) while XO inhibition alleviated the accompanying ischemia. In addition, XO inhibition prevented the elevation of serum 8-isoprostane and TNFα, and blocked elevated AngII and AT1 receptor expression in the heart tissue of IR animals. However, XO inhibition did not affect the developed hyperinsulinemia or dyslipidemia. CONCLUSIONS: XO inhibition alleviates cardiac ischemia and impaired relaxation in IR through the inhibition of low grade inflammation and the angiotensin system.

Degradation of anthraquinone dye reactive blue 4 in pyrite ash catalyzed Fenton reaction.

Pyrite ash (PA) is created by burning pyrite in the chemical production of sulphuric acid. The high concentration of iron oxide, mostly hematite, present in pyrite ash, gives the basis for its application as a source of catalytic iron in a modified Fenton process for anthraquinone dye reactive blue 4 (RB4) degradation. The effect of various operating variables such as catalyst and oxidant concentration, initial pH and RB4 concentration on the abatement of total organic carbon, and dye has been assessed in this study. Here we show that degradation of RB4 in the modified Fenton reaction was efficient under the following conditions: pH=2.5; [PA]0=0.2 g L(-1); [H2O2]0=5 mM and initial RB4 concentration up to 100 mg L(-1). The pyrite ash Fenton reaction can overcome limitations observed from the classic Fenton reaction, such as the early termination of the Fenton reaction. Metal (Pb, Zn, and Cu) content of the solution after the process suggests that an additional treatment step is necessary to remove the remaining metals from the water. These results provide basic knowledge to better understand the modified, heterogeneous Fenton process and apply the PA Fenton reaction for the treatment of wastewaters which contains anthraquinone dyes.

Evaluating the effectiveness of a low fidelity, easily available simulator to teach basic arthroscopy skills to novice learners: A prospective cohort study.

BACKGROUND: Arthroscopy proficiency is key to being a competent orthopaedic surgeon and acquiring arthroscopic skills takes years of exposure and diligent practice. However, today's graduating consultants have had considerably less time in operating theatre than their senior colleagues at the same point of their careers. OBJECTIVES: To evaluate whether: (1) Students could improve their arthroscopic technique using a low fidelity arthroscopic training tool (2) students enjoyed the use of the simulator (3) If certain demographics correlate to performance on the simulator. METHODS: Medical students who have no previous training in arthroscopy were included. A combined left- and right-handed timed run with a low-fidelity arthroscopic triangulation simulator was recorded before and after 40-minutes of practice. RESULTS: 84 participants took part with an average improvement of was 66.8%. Students felt that their arthroscopic skills increased on average by 36.4%. 73 of the 84 participants gave the maximum score of 5 when asked if they enjoyed the session and 74 participants gave the maximum score of 5 as to whether they would be interested in participating in further sessions. Factors such as biological sex, video game play and sports were found to be statistically significant to performance. CONCLUSIONS: This study showed a statistically significant improvement in students' arthroscopic performance with a low-fidelity arthroscopic simulator. Students found the experience useful with the vast majority indicating interest in completing further training sessions to help improve practical surgical skills. Video gamers, sports players and males were found to have a correlation with performance on the simulator.

Insight into changes during coagulation in NOM reactivity for trihalomethanes and haloacetic acids formation.

Natural organic matter (NOM) in raw water can contribute in many ways to the poor quality of drinking water, including the formation of disinfection byproducts such as trihalomethanes (THM) and haloacetic acids (HAA) during disinfection. This paper investigates the role of individual NOM fractions on changes in THM and HAA formation during coagulation with iron chloride (FeCl3) and a combination of polyaluminium chloride and iron chloride (FeCl3/PACl). The dissolved organic carbon (DOC) in the raw water and after coagulation was fractionated into four fractions, based on their hydrophobicity. Fractionation showed that most of the DOC (68%) in the raw water comes from the fulvic acid fraction, yielding 41% of the total THM precursors and 21% of the total HAA precursors. Both coagulants remove the humic acid fraction, but result in different changes to the reactivity of the remaining NOM fractions towards THM and HAA formation, indicating that coagulation occurs by different pathways, depending upon the type of coagulant used. In particular, significant changes in the reactivities of the hydrophilic acidic and non-acidic fractions were observed.

Correlation of different pollution criteria in the assessment of metal sediment pollution.

In this article an assessment of the sediment metal pollution (cadmium, copper, chromium, lead, nickel, zinc) in the Veliki Backi canal (Serbia) was carried out using pseudo-total metal content, contamination factor (CF), pollution load index (PLI) and enrichment factor (EF). The study also encompassed pore-water metal concentrations and an assessment of sediment pollution based on the analysis of simultaneously extracted metals (SEM), acid volatile sulphides (AVS) and the sequential extraction procedure. The concentrations of metals are likely to result in harmful effects based on the comparison with sediment quality guidelines (Dutch, Canadian, US EPA - United States Environmental Protection Agency). The ratio of simultaneously extracted metals and volatile acid sulphides was found to be greater than 1 in only one location, which is already recognized as a place of high risk based on the criteria applied. Other samples had Σ[SEM]/[AVS] < 1, despite their high risk classification based on the applied criteria. According to the sequential extraction procedure, zinc and nickel exhibit high risk in most samples, whereas other metals show low and medium risk. The CF values for Cr, Cu and Zn were > 6 in most samples, which denotes very high contamination by these metals. The PLI values indicated moderate and high pollution. The EF values for all metals studied except for Cd in some cases were >1.5, suggesting anthropogenic impact. The obtained results will be invaluable for future activities regarding sediment monitoring and will facilitate the selection of appropriate criteria when evaluating sediment quality.

Prospective randomised unblinded comparison of sputum viscosity for three methods of saline nebulisation in mechanically ventilated patients: A pilot study protocol.

INTRODUCTION: Heat and moisture exchanger (HME) filters are commonly used as passive circuit humidifiers during mechanical ventilation, however, are only ~80% efficient. As a result, patients that undergo mechanical ventilation in critical care with HME filter circuits will be exposed to partial airway humidification. This is associated with detrimental effects including increased secretion load which has been shown to be an independent predictor of failed extubation. Nebulised normal saline is commonly utilised to supplement circuit humidification in ventilated patients with high secretion loads, although there are no randomised control trials evaluating its use. Novel vibrating mesh nebulisers generate a fine aerosol resulting in deeper lung penetration, potentially offering a more effective means of nebulisation in comparison to jet nebulisers. The primary aim of this study is to compare the viscosity of respiratory secretions after treatment with nebulised normal saline administered via vibrating mesh nebuliser or jet nebuliser. METHODS AND ANALYSIS: This randomised controlled trial is enrolling 60 mechanically ventilated adult critical care patients breathing on HME filter circuits with high secretion loads. Recruited patients will be randomised to receive nebulised saline via 3 modalities: 1) Continuous vibrating mesh nebuliser; 2) Intermittent vibrating mesh nebuliser or 3) Intermittent jet nebuliser. Over the 72-hr study period, the patients' sputum viscosity (measured using a validated qualitative sputum assessment tool) and physiological parameters will be recorded by an unblinded assessor. A median reduction in secretion viscosity of ≥0.5 on the qualitative sputum assessment score will be deemed as a clinically significant improvement between treatment groups at analysis. DISCUSSION: At the conclusion of this trial, we will provisionally determine if nebulised normal saline administered via vibrating mesh nebulisation is superior to traditional jet nebulisation in terms of reduced respiratory secretion viscosity in intubated patients. Results from this pilot study will provide information to power a definitive clinical study. TRIAL REGISTRATION: ClinicalTrails.Gov Registry (NCT05635903).

Study protocol for IMPRoVE: a multicentre prospective observational cohort study of the incidence, impact and mechanisms of perioperative right ventricular dysfunction in non-cardiac surgery.

INTRODUCTION: Perioperative myocardial injury evidenced by elevated cardiac biomarkers (both natriuretic peptides and troponin) is common after major non-cardiac surgery. However, it is unclear if the rise in cardiac biomarkers represents global or more localised cardiac injury. We have previously shown isolated right ventricular (RV) dysfunction in patients following lung resection surgery, with no change in left ventricular (LV) function. Given that perioperative RV dysfunction (RVD) can manifest insidiously, we hypothesise there may be a substantial burden of covert yet clinically important perioperative RVD in other major non-cardiac surgical groups. The Incidence, impact and Mechanisms of Perioperative Right VEntricular dysfunction (IMPRoVE) study has been designed to address this knowledge gap. METHODS AND ANALYSIS: A multicentre prospective observational cohort study across four centres in the West of Scotland and London. One hundred and seventy-five patients will be recruited from five surgical specialties: thoracic, upper gastrointestinal, vascular, colorectal and orthopaedic surgery (35 patients from each group). All patients will undergo preoperative and postoperative (day 2-4) echocardiography, with contemporaneous cardiac biomarker testing. Ten patients from each surgical specialty (50 patients in total) will undergo T1-cardiovascular magnetic resonance (CMR) imaging preoperatively and postoperatively. The coprimary outcomes are the incidence of perioperative RVD (diagnosed by RV speckle tracking echocardiography) and the effect that RVD has on days alive and at home at 30 days postoperatively. Secondary outcomes include LV dysfunction and clinical outcomes informed by Standardised Endpoints in Perioperative Medicine consensus definitions. T1 CMR will be used to investigate for imaging correlates of myocardial inflammation as a possible mechanism driving perioperative RVD. ETHICS AND DISSEMINATION: Approval was gained from Oxford C Research Ethics Committee (REC reference 22/SC/0442). Findings will be disseminated by various methods including social media, international presentations and publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT05827315.

The use of joints of meat as phantoms for ultrasound-guided needling skills: a prospective blinded study.

BACKGROUND: Needle visualisation during ultrasound-guided procedures is a skill that can be difficult to practise, with commercially available phantoms being expensive and often unrealistic. Our aim was to find an inexpensive, reproducible model that could be used to assist in developing this skill. METHODS: Pork shoulder, beef brisket, and lamb shoulder joints were compared to a standard blue ultrasound phantom. Five 'chunky' yarn pieces were twisted together and threaded through each joint to simulate hyperechoic nerves. Participants were instructed to ultrasound each specimen and insert a needle close to a nerve like structure. Using a visual analogue scale, specimens were scored based on realism of appearances of ultrasound images and 'feel' of needling. RESULTS: 38 people participated. All specimens of meat scored significantly higher than the blue phantom (p = 0.01). There was no significant difference between the different types of meat. CONCLUSIONS: Pork, beef and lamb joints are an effective model to use for simulation training for needling skills. They have limited lifespan, but due to its relatively low cost, it is feasible to discard the meat after each training workshop. We hope the use of inexpensive meat products will make ultrasound simulation training simpler to organise and more effective.

Expression and agonist responsiveness of CXCR3 variants in human T lymphocytes.

The chemokine receptor CXCR3 and its ligands CXCL9, CXCL10 and CXCL11 are involved in variety of inflammatory disorders including multiple sclerosis, rheumatoid arthritis, psoriasis and sarcoidosis. Two alternatively spliced variants of the human CXCR3-A receptor have been described, termed CXCR3-B and CXCR3-alt. Human CXCR3-B binds CXCL9, CXCL10, CXCL11 as well as an additional ligand CXCL4. In contrast, CXCR3-alt only binds CXCL11. We report that CXCL4 induces intracellular calcium mobilization as well as Akt and p44/p42 extracellular signal-regulated kinase phosphorylation, in activated human T lymphocytes. These responses have similar concentration dependence and time-courses to those induced by established CXCR3 agonists. Moreover, phosphorylation of Akt and p44/p42 is inhibited by pertussis toxin, suggesting coupling to Gα(i) protein. Surprisingly, and in contrast with the other CXCR3 agonists, stimulation of T lymphocytes with CXCL4 failed to elicit migratory responses and did not lead to loss of surface CXCR3 expression. Taken together, our findings show that, although CXCL4 is coupled to downstream biochemical machinery, its role in T cells is probably distinct from that of CXCR3-A agonists.

Ionic Liquids: Review of their Current and Future Industrial Applications and their Potential Environmental Impact.

BACKGROUND: Over the last two decades, thousands of scientific papers and many patents have been written relating to applications of ionic liquids, a family of compounds that garnered such huge interest due to their reputation as "green chemicals". This work reviews the recent literature to investigate the progress ionic liquids have made in their transition from academia to full-scale application in a variety of industries. METHODS: For this review, keywords related to ionic liquids and their possible applications were used to search patent databases such as Google patents. The recent patents thus discovered were tabulated and sorted by application, and the most significant patents were identified. For each application of ionic liquids identified in the patent search, an additional review of the recent scientific literature was carried out, focussing on the relevant ionic liquids and their potential environmental impact. RESULTS: Patents involving ionic liquids were found for various industrial applications, including in chemical industry production technologies, nanotechnology, gas storage and environmental remediation. Despite the widespread interest of the chemical industry, which hopes to improve the environmental sustainability of their technologies by utilising ionic liquids, to date, only a handful of full-scale processes which utilise ionic liquids have been successfully commercialised. That said, a large number of pilot studies have been carried out in recent years, and 62 patents and 270 scientific texts are summarised herein and other industrial applications are also approaching the market. CONCLUSION: The properties of ionic liquids inhibit their entry into the atmosphere. However, their annual production is expected to increase drastically, raising urgent questions about their environmental impact, especially in water bodies. More research is thus required to identify and mitigate any risks ionic liquids might pose to the environment.

Application of Nanomaterials in Water Treatment: Arsenic and Natural Organic Matter Removal.

BACKGROUND: Globally, around 150 million people are still supplied with arsenic contaminated drinking water. The groundwaters effected often contain problematic concentrations of natural organic matter (NOM), which plays an important role in releasing As into the aquifer. Thus, this review explores the recent literature relating to the application of various nanomaterials to solve these drinking water supply problems and highlights the work that still needs to be done. METHODS: After an extensive initial search patent papers were selected based on their quality and relevance to the topic of this review: the use of magnetic nanomaterials based on pure magnetic materials, magnetic composites of carbon/graphene/biochars, polymeric matrices, metal-organic frameworks and mixed-oxide magnetic nanocomposites, as As adsorbents and as photocatalysts for NOM removal. RESULTS: 160 papers relating to the application of nanomaterials for As removal were reviewed and 38 papers covering photocatalysts for NOM removal. These papers were organised by type of nanomaterial, and their important findings summarised. Although many authors have demonstrated effective solutions in the laboratory, the following areas still need to be addressed: the challenges posed by larger pilot and full scale continuously operated processes; the treatment of complex natural water matrices; which technologies will be required to economically separate nanoparticles from the treated water; whether the nanoparticles will be more economically and environmentally sustainable than other techniques available. CONCLUSION: Despite these significant gaps in the literature, the body of work carried out thus far, as summarised in this review paper, strongly suggests that full scale treatment solutions applying (magnetic) nanomaterials may prove highly effective in the future for both arsenic and NOM removal.

Roots of Apium graveolens and Petroselinum crispum-Insight into Phenolic Status against Toxicity Level of Trace Elements.

Celery (Appium graveolens L.) and parsley (Petroselinum crispum (Mill.) Fuss) are herbs utilized in the everyday diet as spices and culinary flavorings, often used in the chemical and medicinal industries. Despite the knowing benefits of different plants from the Apiaceae family, their chemical composition is closely associated with various extrinsic factors. Environmental loading with trace elements (TEs) can modify a plant's metabolic pathways, change bioactive compounds production, cause plant pollution, and consequently provoke human health issues. Therefore, we established this research aiming to unravel the linkage between TEs accumulation and phenolic status in celery and parsley. Higher As, Cd, and Ni levels were observed in celery, which was followed by greater DPPH∙ radical scavenging activity and higher coumarins content. Contrary, parsley accumulated chromium to a greater extent, was richer in flavonoids, apigenin, and its glucosides. No significant difference between species was found in total phenolic contents, where ferulic and chlorogenic acid dominated in both species. A direct relationship between TEs and selected secondary metabolites was proven by the standardized major axis model. Besides abundant bioactive compounds, analyzed plant species showed a moderate hazard index in the children population, since the hazard index was higher than 1. Therefore, future perspectives should be turned towards the production of genotypes with a lower potential for toxic elements accumulation, so the health benefits of plant food will be more prominent.

Fate of natural organic matter and oxidation/disinfection by-products formation at a full-scale drinking water treatment plant.

This paper investigates the fate of natural organic matter (NOM) during the full-scale drinking water treatment plant supplied by Danube river bank filtration. After the recent reconstruction of the plant, special attention was devoted to the effects of ozone dose and granulated activated carbon (GAC) filtration on the formation and behaviour of oxidation by-products (carbonyl compounds and bromate), as well as carbonaceous and nitrogenous chlorination by-products. For the oxidation of aromatic NOM moieties that absorb light at UV254, a lower ozone dose (1.0 g O3/m3) is sufficient, whereas to achieve a measurable reduction (about 20%) of total organic carbon, an ozone dose of 1.5 g O3/m3 is required. The content of carbonyl compounds in the water after ozonation increases relative to the content before oxidation treatment, and is up to 12 times higher in the case of aldehydes and up to 2 times higher in the case of carboxylic acids. Seasonal variations, including changes in temperature and the amount of precipitation, were also shown to affect the content of organic matter in the raw water, with slight effects on the quality of the treated water. In the winter, the organic matter content is slightly higher, meaning their transformation products aldehydes and carboxylic acids, are also higher during the winter than the summer.

Synthesis, characterization and application of magnetic nanoparticles modified with Fe-Mn binary oxide for enhanced removal of As(III) and As(V).

Arsenic contamination of drinking water sources is a widespread global problem. Of the As species commonly found in groundwater, As(III) is generally more mobile and toxic than As(V). In this work, magnetic nanoparticles (MNp) modified with Fe-Mn binary oxide (MNp-FeMn) were synthesized in order to develop a low cost adsorbent with high removal efficiency for both arsenic species which can be readily separated from water using a magnetic field. MNp-FeMn were characterized using different techniques including SEM/EDS, XRD and BET analysis. Adsorption of As(III) and As(V) on MNp-FeMn was studied as a function of initial arsenic concentration, contact time, pH, and coexisting anions. The BET specific surface area of MNp-FeMn was 109 m2/g and maghemite (γ-Fe2O3) was the dominant precipitated phase. The adsorption rate of As(III) and As(V) on MNp-FeMn was controlled by surface diffusion. FTIR analysis confirms that surface complexation through ligand exchange was the main mechanism for As(III) and As(V) removal on MNp-FeMn, with As(III) conversion to As(V) occurring on the adsorbent surface. The maximal adsorption capacity qmax of MNp for As(III) (26 mg/g) was significantly improved after modification with Fe-Mn binary oxide (56 mg/g), while qmax for As(V) was 51 and 54 mg/g, respectively. PO43-, SiO32- and CO32- reduced As(III) and As(V) uptake at higher concentrations. MNp-FeMn can be easily regenerated and reused with only a slight reduction in adsorption capacity. The high oxidation and sorption capacity of MNp-FeMn, magnetic properties and reusability, suggest this material is a highly promising adsorbent for treatment of arsenic contaminated groundwater.