Tertiary Treatment Research Articles

To what extent do water reuse treatments reduce antibiotic resistance indicators? A comparison of two full-scale systems

Water reuse is an essential strategy for reducing water demand from conventional sources, alleviating water stress, and promoting sustainability, but understanding the effectiveness of associated treatment processes as barriers to the spread of antibiotic resistance is an important consideration to protecting human health. We comprehensively evaluated the reduction of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) in two field-operational water reuse systems with distinct treatment trains, one producing water for indirect potable reuse (ozone/biologically-active carbon/granular activated carbon) and the other for non-potable reuse (denitrification-filtration/chlorination) using metagenomic sequencing and culture. Relative abundances of total ARGs/clinically-relevant ARGs and cultured ARB were reduced by several logs during primary and secondary stages of wastewater treatment, but to a lesser extent during the tertiary water reuse treatments. In particular, ozonation tended to enrich multi-drug ARGs. The effect of chlorination was facility-dependent, increasing the relative abundance of ARGs when following biologically-active carbon filters, but generally providing a benefit in reduced bacterial numbers and ecological and human health resistome risk scores. Relative abundances of total ARGs and resistome risk scores were lowest in aquifer samples, although resistant Escherichia coli and Klebsiella pneumoniae were occasionally detected in the monitoring well 3-days downgradient from injection, but not 6-months downgradient. Resistant E. coli and Pseudomonas aeruginosa were occasionally detected in the nonpotable reuse distribution system, along with increased levels of multidrug, sulfonamide, phenicol, and aminoglycoside ARGs. This study illuminates specific vulnerabilities of water reuse systems to persistence, selection, and growth of ARGs and ARB and emphasizes the role of multiple treatment barriers, including aquifers and distribution systems.

Effect of floating treatment wetland coverage ratio and operating parameters on nitrogen removal: toward design optimization.

Floating treatment wetlands (FTWs) have the potential to improve the quality of wastewater discharges, yet design basics are unavailable to size these systems. This study investigates the effect of FTWs' coverage ratio and hydraulic retention time on agri-food wastewater treatment. This was studied in a pilot-scale experiment comprising four lagoons (6.5 m3 each) fed with real effluent from an existing tertiary treatment lagoon. An evaluation of FTW of different sizes (L24, L48, and L72 representing 24, 48, and 72% of pilot lagoons surface areas) and a control, L0 (without FTW), was performed over 16 months. Overall, L72 and L48 moderately improved total nitrogen (TN) mass removal compared to L0 (p < 0.05), while L24 exhibited similar TN mass removal (p = 0.196). The highest improvement was observed for L72, exhibiting up to 55% (mean of 13%) greater N mass removal than the control. The net increase in TN removal by FTWs was mainly related to denitrification, promoted by decreasing dissolved oxygen for increasing FTW coverage ratio. Residence time, temperature, and dissolved oxygen were the main parameters driving TN removal by FTWs. Retrofitting existing lagoons with FTW can facilitate N retrieval through plant harvesting, thereby reducing N remobilization from sediment (common in conventional lagoons).

The fate of antibiotic resistance genes in wastewater containing microalgae treated by chlorination, ultra-violet, and Fenton reaction

Antibiotic resistance genes (ARGs) and bacteria (ARBs) in the effluent of wastewater treatment plants (WWTPs) are of utmost importance for the dissemination of ARGs in natural aquatic environments. Therefore, there is an urgent need for effective technologies to eliminate WWTP ARGs/ARBs and mitigate the associated risks posed by the discharged ARG in aquatic environments. To test the effective technology for eliminating ARGs/ARBs, we compared the removal of ARGs and ARBs by three different tertiary treatments, namely ultra-violet (UV) disinfection, chlorination disinfection, and Fenton oxidation. Then, the treated wastewater was co-cultured with Chlorella vulgaris (representative of aquatic biota) to investigate the fate of discharged ARGs into the aquatic environment. The results demonstrated that chlorination (at a chlorine concentration of 15 mg/L) and Fenton (at pH 2.73, with 0.005 mol/L Fe2+ and 0.0025 mol/L H2O2) treatment showed higher efficacy in ARG removal (1.8 - 4.17 logs) than UV treatment (15 min) (1.29 - 3.87 logs). Moreover, chlorine at 15 mg/L and Fenton treatment effectively suppressed ARB regeneration while UV treatment for 15 min could not. Regardless of treatments tested in this study, the input of treated wastewater to the Chlorella system increased the number of ARGs and mobile genetic elements (MGEs), indicating the potential risk of ARG dissemination associated with WWTP discharge. Among the wastewater-Chlorella co-culture systems, chlorination resulted in less of an increase in the number of ARGs and MGEs compared to Fenton and UV treatment. When comparing the wastewater systems to the co-culture systems, it was observed that Chlorella vulgaris reduced the number of ARGs and MGEs in chlorination and UV-treated wastewater; however, Chlorella vulgaris promoted ARG survival in Fenton-treated water, suggesting that aquatic microalgae might act as a barrier to ARG dissemination. Overall, chlorination treatment not only effectively removes ARGs and inhibits ARB regeneration but also shows a lower risk of ARG dissemination. Therefore, chlorination is recommended for practical application in controlling the spread of discharged ARGs from WWTP effluent in natural aquatic environments.

The Efficacy of Activated Carbon from Organic Waste in Treating Wastewater Effluent

Increasing population growth with high socio-economic development has changed the world landscape. These advancements have resulted to the water quality degradation and inadequate management of solid waste. In addressing these critical issues, a robust water treatment technology is required. Activated carbon (AC) in enhancing thewastewater effluent quality has proven to be a promising and sustainable solution. AC from sugarcane bagasse (SCB), empty fruit bunch (EFB), and rice husk (RH) have been identified as abundant bioresources in Malaysia. These materials possess unique compositions and potential for reuse. The production of AC involves both physical activation through a carbonization processat 600°C and chemical activation through impregnation with ZnCl2. In the study, samples from wastewater effluent were collected and analyzed for several parameters, including total suspended solids (TSS), chemical oxygen demand (COD), biochemical oxygen demand (BOD), ammonia-nitrogen, nitrite-nitrogen, and nitrate-nitrogen. The samples have undergone treatment using activated carbon with various ratios. Here, the removal efficiency of pollutants was determined before and after the batch experiment. It can be denoted that AC, composed of SCB:EFB:RH in a ratio of 1.5:1:1, demonstrated an outstanding performance with an average percentage removal of 97%. Adetailed analysis of the physicochemical characteristics of the AC was conducted. The output revealed significant surface modifications and alterations in the functional groups of the AC due to the adsorption process. These findings set a remarkable implication for tertiary treatment in enhancing the quality of effluent and provides valuable insight into implementing sustainable practices in wastewater treatment operations.

Treatment and referral patterns of patients with atopic dermatitis from the Danish primary care system to the tertiary care system

AbstractBackgroundPatients with atopic dermatitis (AD) are mostly managed by general practitioners (GPs) and practicing dermatologists (PDs) in Denmark. In cases of severe and refractory AD, the primary physician can refer the patient to a specialised dermatology department.ObjectivesAim of the study was to investigate treatment at the time of referral to a specialised dermatology department and the cause stated by the GP in a Danish cohort of AD patients referred to the Department of Dermatology, Aarhus University Hospital from 2019 to 2021.MethodsOne hundred and thirty cases were randomly selected via diagnosis codes for AD. Information regarding the cause for referral and treatment given at time of referral was obtained from medical records. 18 cases were excluded due to missing referral in the patients' medical records, other diagnosis than AD or treatment initiation before 2019. The final cohort consisted of 112 cases. Differences between patients referred from GP and PD were analysed with Fisher's exact test.ResultsMost cases were referred by PDs (45.5%) and GPs (24.1%). GPs primarily referred due to acute flare‐ups in need of treatment (40.7%), and PDs due to lacking disease control (64.7%), (p‐values &lt; 0.0018). GPs generally included more descriptive information in their referrals than PDs, however, only the difference in mentioning sleep disturbance was significant (p‐value = 0.0144). Topical corticosteroids were the preferred treatments before referral regardless of the referring doctor, with no statistical differences. Topical calcineurin inhibitors were significantly more used among PD‐referred patients compared to GP‐referred patients (p‐value = 0.0018). Systemic therapy was initiated in 45 patients (40.2%) at the tertiary hospital with no differences between referral from either GPs or PDs.ConclusionsThe study identified few differences in the referral pattern of AD to a tertiary treatment center from GPs and PDs. No major deviations from Danish guidelines were found.

Second life of water and wastewater in the context of circular economy – Do the membrane bioreactor technology and storage reservoirs make the recycled water safe for further use?

In recent years water demand drastically increased which is particularly evident in tourism-burdened mountain regions. In these areas, climate neutral circular economy strategies to minimize human impact on the environment can be successfully applied. Among these strategies, treated wastewater reuse and retaining water in storage reservoirs deserve particular attention. This study aimed to determine if recycled water produced with two circular economy systems, namely membrane bioreactor treatment plant (MBR) with UV-light effluent disinfection and a storage reservoir, is safe enough for further use in green areas irrigation in summer and artificial snow production in winter. The assessment was based on the presence and concentration of antimicrobial agents, antibiotic resistant bacteria, antibiotic resistance genes, bacterial community composition and diversity. The treated water and wastewater was compared with natural water in their vicinity. Both systems fulfill the criteria set by the European Union in terms of reclaimed water suitable for reuse. Although the MBR/UV light wastewater treatment substantially reduced the numbers of E. coli and E. faecalis (from e.g. 32,000 CFU/100 ml to 20 CFU/100 ml and 15,000 CFU/100 ml to nearly 0 CFU/ml), bacteria resistant to ampicillin, aztreonam, cefepime, ceftazidime, ertapenem and tigecycline, as well as ESBL-positive and multidrug resistant E. coli were highly prevalent in MBR-treated wastewater (88.9 %, 55.6 %, 33.3 %, 22.2 % and 11.1 % and 44.4 and 55.6 %, respectively). Applying additional tertiary treatment technology is recommended. Retaining water in storage reservoirs nearly eliminated bacterial contaminants (e.g. E. coli dropped from 350 CFU/100 ml to 10 CFU/100 ml), antibiotic resistant bacteria, resistance genes (none detected in the storage reservoir) and antibiotics (only enrofloxacin detected once in the concentration of 3.20 ng/l). Findings of this study point to the limitations of solely culture-based assessment of reclaimed water and wastewater while they may prove useful in risk management and prevention in wastewater reuse.

Coagulative removal of polystyrene microplastics from aqueous matrices using FeCl3-chitosan system: Experimental and artificial neural network modeling

Effluent from sewage treatment plants (STPs) is a significant source of microplastics (MPs) re-entry into the environment. Coagulation-flocculation-sedimentation (CFS) process as an initial tertiary treatment step requires investigation for coagulative MPs removal from secondary-treated sewage effluents. In this study, experiments were conducted on synthetic water containing 25 mg/L polystyrene (PS) MPs using varying dosages of FeCl3 (1–10 mg/L) and chitosan (0.25–9 mg/L) to assess the effect of process parameters, such as pH (4−8), stirring speed (0–200 rpm), and settling time (10–40 min). Results revealed that ∼89.3% and 21.4% of PS removal were achieved by FeCl3 and chitosan, respectively. Further, their combination resulted in a maximum of 99.8% removal at favorable conditions: FeCl3: 2 mg/L, chitosan: 7 mg/L, pH: 6.3, stirring speed: 100 rpm, and settling time: 30 min, with a statistically significant (p < 0.05) effect. Artificial neural network (ANN) validated the experimental results with RMSE = 1.0643 and R2 = 0.9997. Charge neutralization, confirmed by zeta potential, and adsorption, ascertained by field-emission scanning electron microscope (FESEM) and Fourier-transform infrared spectroscopy (FTIR), were primary mechanisms for efficient PS removal. For practical considerations, the application of the FeCl3-chitosan system on the effluents from moving bed biofilm reactor (MBBR) and sequencing batch reactor (SBR)-based STPs, spiked with PS microbeads, showed > 98% removal at favorable conditions.

Sequential Treatment by Ozonation and Biodegradation of Pulp and Paper Industry Wastewater to Eliminate Organic Contaminants.

In this research, the decomposition of toxic organics from pulp and paper mill effluent by the sequential application of ozonation and biodegradation was studied. Ozonation, as a pre-treatment, was executed to transform the initial pollutants into less toxic compounds (such as organic acids of low molecular weights). Biodegradation was executed during three days with acclimated microorganisms that were able to complete the decomposition of the initial organic mixture (raw wastewater) and to achieve a higher degree of mineralization (85-90%). Experiments were performed under three different conditions: (a) only ozonation of the initial contaminants, (b) only biodegradation of residual water without previous treatment by ozone and (c) ozonation followed by biodegradation performed by acclimated microorganisms. In the case of 72 h of biodegradation, the mineralization efficiency reached 85% and 89% after 30 and 60 min of ozonation, respectively. The no significant difference in this parameter coincided with the calculated generalized microorganisms' consortia specific growing rate μmax that was reduced from 2.08 × 10-3 h-1 to 6.05 × 10-4 h-1 when the ozonation time was longer. The identification of the organics composition by gas chromatography with mass detector (GC-MS) before and after treatments confirmed that the proposed combined process served as a more efficient alternative to secondary and tertiary treatments (mineralization degree between 60 and 80% in average) of the paper industry wastewater.

Assessment and Upgrading of Preparation Protocols for Emulsified Crude Oils Mimicking Real Produced Water Characteristics

AbstractProduced water (PW) presents a significant challenge as a complex wastewater stream, necessitating thorough treatment prior to disposal or further reuse. This study is dedicated to the assessment, reproduction and upgrading of literature‐based preparation protocols for synthetic PW at the tertiary treatment stage; more specifically those methods utilizing high‐pressure homogenizers and ultrasonication. The objective was to produce synthetic model water that can be employed as a standardized controllable medium for optimization experiments of PW treatment techniques. This synthetic medium should facilitate the investigation of specific challenges associated with PW tertiary treatment, independent of the different and often unpredictable composition of real PW. The refined methods were modified for the application in lab‐scale research investigating the use of membrane filtration as tertiary treatment step.

Fate of contaminants of emerging concern in two wastewater treatment plants after retrofitting tertiary treatment for reduction of nitrogen discharge

More and more previously designed wastewater treatment plants (WWTPs) are upgraded to tertiary treatment to meet the higher effluent discharge standards of conventional pollutants. Contaminants of emerging concern (CECs) can cause adverse effects on organisms and usually flow into WWTPs along with urban sewage. How the retrofitted WWTPs targeting conventional pollutants will influence the treatment efficiency of CECs is seldom discussed. This study investigates the removal of CECs in two full-scale newly retrofitted WWTPs (CD and JM WWTPs), containing high-efficiency sedimentation tank and denitrification deep bed filter for enhancing total nitrogen removal. The overall CEC removal efficiencies in the CD and JM WWTPs were 73.79 % and 93.63 %, respectively. Mass balance results indicated that CD WWTP and JM WWTP release a total of 36.89 and 88.58 g/d of CECs into the environment through effluent and excess sludge, respectively. Analysis of the concentration of CECs along the treatment process revealed most CECs were removed in the biological treatment units. The incorporation of newly constructed tertiary treatment proved beneficial for CEC removal and removed 2.93 % and 2.36 % CECs, corresponding to CEC removal of 2.92 and 27.49 g/d in the CD and JM WWTPs, respectively. The data of this study were further used to evaluate the suitability of the SimpleTreat model for simulating the fate of CECs in WWTPs. The predicted fraction of CECs discharged through the biological treatment effluent were generally within ten-fold difference from the measured results, highlighting its potential for estimating CEC removal in WWTPs.

Potential and risks of water reuse in Brandenburg (Germany) – an interdisciplinary case study

Abstract For Brandenburg, a region in Germany with increasing water shortage and drought events, water reuse can counteract competition scenarios between drinking water supply, agricultural irrigation, and industrial use. Centralized and decentralized sources for reclaimed water are found to potentially substitute 245 or 28% of irrigation water, respectively, in agriculture production in Brandenburg. For such a reuse scenario, the fate of organic micro-pollutants is examined for diatrizoate (DZA) and carbamazepine (CBZ). Retention in local sandy soil and transfer into roots and leaves of arugula are analyzed in lysimeter studies and greenhouse pot experiments. Vertical transport was found for DZA and accumulation in or on arugula roots with a root concentration factor of 1,925 ± 34% but a low bioconcentration factor due to intrinsic molecule properties. CBZ was not found to be mobile in the sandy soil but accumulates in arugula roots and leaves by factors of 70 ± 7% and 155 ± 12%, respectively. Further research on potential plant uptake and groundwater enrichment for more substances is highly recommended as well as tertiary wastewater treatment prior to water reuse.

Pituitary Adenoma Prevalence and Characteristics of Omani Patients: A Single Center Experience.

To estimate the incidence of pituitary adenomas (PA) in adult Omani patients and describe its epidemiological, clinical, and radiological characteristics. In this longitudinal, descriptive study, we reviewed the records of all PA patients from January 2015 to January 2020 who presented at the endocrinology facilities at Sultan Qaboos University Hospital, Muscat. The participants comprised of 112 Omani patients with PA. The incidence of PA among all adult patients at Sultan Qaboos University Hospital (inpatient and outpatient) over five years (2015-2020) was 0.23%. The cohort had a mean age of 41.0±15.0 years. Of the 112 patients included in this study, 79 (70.5%) were women. Nearly half (51; 45.5%) of adenomas were prolactinomas while 46 (41.1%) were non-functioning adenomas, and seven (6.3%) were growth hormone-secreting adenomas while six (5.4%) were adrenocorticotropic hormone secreting adenomas. Headache was present in 67 (59.8%) patients, followed by visual field defects (40; 35.7%), galactorrhea (26; 23.2%), and fatigue (19; 17.0%). The majority of women (45/79; 57.0%) presented with menstrual cycle abnormalities. Radiological appearances were nearly equally distributed between micro- and macroadenomas. Most cases (58/112; 52.0%) of PA were treated medically by cabergoline, octreotide, and replacement therapies such as hydrocortisone and thyroxin, 38 (33.9%) were treated surgically (mainly by trans-sphenoidal pituitary resection), and the remaining 10 (8.9%) cases were subjected to radiotherapy. Medical treatment combined with surgery was employed for 15 (13.4%) patients. In our investigation, PA was primarily prevalent among Omani female patients, and the most common subtype of pituitary tumors was prolactinomas. The most common presentation symptom was headaches; most female patients had menstrual irregularities. Medical treatment was the primary approach for the applicable types of PAs, while surgery and radiotherapy were found to be secondary and tertiary treatment options, respectively.

Effect of treated wastewater irrigation on ornamental plants: Case study of Lantana and Hibiscus, Morocco

AbstractIn water stressed countries such as Morocco, the use of treated wastewater represents a strategic perspective for sustainable agricultural development. However, technological and management innovations are needed to make it feasible and effective. The main objective of this work is to evaluate the effect of irrigation with treated wastewater compared with fresh water on the growth of two ornamental plants: Rosa Sinensis hibiscus and Lantana Camara. The study also aimed to examine the impact of treated wastewater on the hydraulic performance of different irrigation systems. To carry out this study, irrigation was applied by two irrigation systems: subsurface drip irrigation and surface drip irrigation. Also, two sources of water were compared: treated wastewater from the WWTP of M'zar (tertiary treatment) and well water, each for a duration of 2 months. The results obtained showed that the treated wastewater generally promoted a better development of agronomic parameters such as height, number of branches, leaves, and flowers for both plants. The same observation was also made regarding the esthetical parameter. For the irrigation system effect, the results obtained showed a better development under the subsurface drip irrigation system; thus, the combination of treated wastewater and subsurface drip irrigation provided the best results for both plants. Regarding the hydraulic performance of the irrigation system, no risk of clogging of the distributors was observed in relation to the water quality; the uniformity coefficient and distribution uniformity remained above 90%. It can therefore be deduced that the use of treated wastewater for irrigation of green spaces should be at the heart of water resource mobilization policies. in fact, it represents an excellent alternative for promoting national water management strategies.

P718 Observational real-world evidence on the efficacy and safety of Janus Kinase inhibitors (JAKi) in the treatment of moderate to severe Active Ulcerative Colitis (UC)

Abstract Background Janus kinase inhibitors (JAKi) are the first orally administered treatment for Ulcerative Colitis (UC). The JAK family comprises of four intracellular tyrosine kinases inhibitors (JAK1, JAK2, JAK3 and Tyrosine Kinase 2). Inhibition of the JAK kinases lead to dampening of the inflammatory cytokines which drive Inflammatory Bowel Disease (IBD). Tofacitinib was the first generation pan-JAKi. This was followed by second generation JAKi: Filgotinib and Upadacinib which preferentially inhibit JAK1. We report on the real-world evidence on the efficacy and safety of JAKi in the treatment of UC in a tertiary IBD treatment centre. Methods Patients attending the IBD clinic at weeks 8-12 of initiation of therapy were included. Baseline demographics, disease activity and previous therapies were recorded. Clinical response was measured using the SCCAI and biochemical response was measured using calprotectin and CRP. We defined clinical response as ≥3 points reduction from baseline SCCAI, and clinical remission as SCCAI Score of &amp;lt;2.5, and / or biochemical remission as a CRP of less than 5 mg/L and a calprotectin level of &amp;lt; 250 mg/g. We also assessed treatment persistence, and the reasons for treatment cessation. Results The UC populations are shown in Table 1. 52 patients were included and an additional 24 patients who discontinued therapy early on were assessed to review secondary outcomes. Table 1 summarises the comparative outcomes of the JAKi. 81% and 63% of patients achieved clinical and biochemical remission respectively. Overall, 31% discontinued treatment due to lack of efficacy or adverse events. 60% of patients reported adverse events (AEs), 25 % of patients discontinued treatment due to AEs and 84% of patients continued treatment despite reporting AEs. The most common AEs were hypercholesteremia and cold and flu like symptoms and the most common AEs related with treatment discontinuation were recurrent infection or persistent deranged liver functions contributed to patients’ history of primary sclerosing cholangitis. No Serious Adverse Events were reported. 60% of patients on tofacitinib developed side effects and persisted with therapy, which included hypercholesteremia (67%), shingles (11%), flu like symptom (11%) and hair loss (11%). 53% had side effects with Filgotinib; hypercholesteremia (25%), cold like symptoms (25%), chest infection (13%), shingles (13%), acne (13%). 68% developed side effects with Upadacitinib; reports of acne (20%), cold and flu (33%), shingles and mood swings (7%) and high cholesterol (67%). Conclusion In this real-world cohort of UC patients, JAKi was effective in inducing remission and had an acceptable safety profile. The observed safety profile was as expected compared to clinical data results.

Human health risk assessment and uncertainty analysis of silver nanoparticles in water.

Despite frequent detection in environmental waters, literature which quantifies the health risk of silver nanoparticles (Ag NPs) through oral ingestion is scarce. This study compiled literature data to find the removal of Ag NPs from different treatment schemes (i.e., natural, engineered, or hybrid). Ag NP concentrations were found either in surface water or in groundwater based on where the effluent of treatment schemes was discharged, i.e.,either in surface water or in groundwater. Monte-Carlo simulation was carried out for probabilistic assessment of health risks for children for two hypothetical exposure scenarios: (a) ingesting river water while swimming and (b) drinking groundwater. Bio-accessible fraction, dietary metal adsorption factor, and concentrations of silver ions were incorporated to simulate realistic situations. Different treatment schemes were ranked for their nanoparticles' removal efficiency with respect to (i) exceedance probability from guideline value and (ii) health risk to children. Hybrid treatment combinations, i.e., conventional primary and secondary treatment units followed by nature-based units (constructed wetlands and soil aquifer treatment), were ranked the best. The health risk value was found to be less than 1, with the 99th percentile value less than 10-3 in all cases. The maximum allowable concentration of Ag NPs was found to be as low as 1.43 mg/L for groundwater, suggesting probable potential for risk. Uncertainty analysis revealed that the uncertainty of the influent NPs concentration in raw wastewater contributes > 99% to the variance of the hazard index. The results of this work indicate that the use of natural treatment technologies with existing engineered treatments provides higher nanoparticle removal from wastewater without the requirement of any tertiary treatment unit.

Pilot test of Mn-Fe/Al2O3 catalytic ozonation in tertiary wastewater treatment

Heterogeneous catalytic ozonation has received increasing popularity in wastewater treatment across China. However, some challenges, such as metal leaching from catalysts, still exist. Meanwhile, it is lesser known about its removal efficiency of dissolved organic carbon and impact on biological toxicity in pilot-scale applications. Here we synthesized an Al-based catalyst (Mn-Fe/Al2O3) for catalytic ozonation in pilot-scale. Results of characterization show that Mn and Fe were effectively supported on porous alumina and formed chemical bonds. The catalytic ozonation process could generate hydroxyl radical, superoxide radical and singlet oxygen for the deep degradation of dissolved organic carbon. Its chemical oxygen demand removal efficiency (average removal of 14.5 mg/L) could meet the requirement of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB 18918-2002) in China with acceptable metal leaching. The process also effectively removed dissolved organic carbon, especially the hydrophobic fractions (99 % removal). In toxicogenomics assay, the total transcriptional effect level index value for the effluent (1.40) was ≤ 1.50, indicating there was no obvious toxic effect for ecosystem. Based on economical estimation, the operational cost of the catalytic ozonation was 0.09 $/m3, much less than previous reported cases. This study provides convincing evidence for the effectiveness of Mn-Fe/Al2O3 catalytic ozonation in future wastewater treatment.

Cross-cultural adaptation and psychometric validation of the brief assessment of recovery capital (BARC-10) scale into Bangla.

Recovery capital is a construct central to the substance use disorder treatment and recovery field. Lack of structured instrument for its assessment in the local context necessitated the translation of the English self-assessment version of the "Brief Assessment of Recovery Capital" (BARC-10) scale to Bangla and the study of its psychometric properties. The objective was to develop a culturally adapted and validated Bangla version of the BARC-10 scale for substance use disorders patients. This study conducted in the period of January 2021 to March 2022 in the department of Psychiatry of a tertiary hospital and central drug addiction treatment center. Initially BARC-10 questionnaire was translated into Bangla (T1 and T2) by 2 separate translators and then synthesis of a single version (T12) was done based on the previous translations. After that 2 back translations (BT1 and BT2) were done by 2 more translators based on the synthesized version (T12). By reviewing all these forward and backward translations, an expert committee made the pre-final version after making some linguistic modification. Then data collection was done among 100 subjects who were selected purposively. Reliability was assessed by Cronbach alpha. Content validity, face validity and Construct validity by factor analysis were measured. Internal consistency measured by Cronbach alpha found was 0.846. No significant change in Cronbach alpha was observed following deleting any item. Confirmatory factor analysis revealed a good fit to data by a chi-square/df value1.33, RMSEA value 0.058. Kaiser-Meyer-Olkin value (.840) showed sampling adequacy. Exploratory factor analysis of the principal component identified 2 factors which had eigenvalues of more than 1. Scree plot also revealed similar factors. These 2 factors together explained 53.1% of the variance. All items were loaded under 2 factors after varimax rotation. The validated Bangla version of the BARC-10 demonstrated high internal reliability and validity. It can potentially be applied in "recovery-oriented" deaddiction service.

Determinants of microbial colonization on microplastics through wastewater treatment processes: The role of polymer type and sequential treatment

This study examines the microbial colonization characteristics of microplastics (MPs) in wastewater treatment plants (WWTPs), focusing on polymer types (High-Density Polyethylene (HDPE) and Polyethylene Terephthalate (PET)) and various stages of wastewater treatments. Through individual and sequential deployment approaches, the research aimed to identify the determinants of bacterial colonization on MPs, whether they were introduced at each stage of treatment individually or in sequence from primary to tertiary stages. The study revealed that the stage of wastewater treatment profoundly influenced bacterial colonization on the polymer types MPs, with bacterial attachment being largely niche-specific. HDPE showed increased sensitivity to wastewater composition, leading to selective biofilm formation. For instance, in HDPE, Firmicutes accounted for 25.1 ± 0.04 % during primary treatment, while Alphaproteobacteria increased significantly in the tertiary treatment to 19.8 ± 0.1 %. Conversely, PET exhibited a stochastic pattern of bacterial colonization due to differences in surface hydrophilicity. Additionally, in sequential deployments, a notable shift towards stochastic bacterial attachment on MPs, particularly with HDPE was observed. The Shannon diversity values for MP biofilms were consistently higher than those for wastewater across all stages, with PET showing an increase in diversity in sequential deployments (Shannon diversity: 5.01 ± 0.03 for tertiary stage). These findings highlight the critical role of MPs as carriers of diverse bacteria, emphasizing the necessity for strategies to mitigate their impact in WWTPs. This study presents a significant advancement in our understanding of the interactions between MPs and microbial populations in WWTP environments.

Methods for eliminating micropollutant from wastewater: A review

The amount of suspended solid and medicinal micropollutants, such as fungicides, personal care products, contraceptive medications, antibiotics and aromatic hydrocarbons are increasing daily and has reached an alarming level. The micropollutant present in wastewater must be treated before its release because it forms adverse effect on mortal health. Because some harmful micropollutants are incredibly difficult to remove from WWTPs because of their nonbiodegradability, poor adsorption capability, complex nature and traditional wastewater treatments are precious or insufficient for decontamination. For the micropollutant declination some of the conventional physicochemical has been used. The use of powdered activated carbon (PAC) for water purification has been proven to be effective without harming the environment. Advanced oxidation technologies (AOTs), typically applied after natural processes have recently emerged as effective tertiary treatments for the withdrawal of micropollutants at high concentrations. Various methods have been developed and studied for the removal of these micropollutants from wastewater. This review aims to provide a comprehensive overview of the different methods employed, including physical, chemical, and biological processes, highlighting their effectiveness and limitations in micropollutant removal. As well as improving treatment efficiency, they can also remove any accumulation of dangerous byproducts produced during treatment.

Effectiveness of wastewater treatment plant at the removal of nutrients, pathogenic bacteria, and antibiotic-resistant bacteria in wastewater from hospital source.

This study is aimed at assessing the effectiveness of hospital's wastewater treatment plant (WWTP) in removing nutrients, pathogenic bacteria, and addressing antibiotic resistance using a case study of a tertiary hospital in Ibadan, Nigeria. During the dry and wet seasons in the month of July and December, respectively, samples were collected, and analyzed using standard guidelines to examine significant physicochemical parameters of the WTTP; to evaluate the removal efficiency of biological oxygen demand (BOD) and chemical oxygen demand (COD), and to examine the prevalence of pathogenic and antibiotic-resistant bacteria. The results of this study showed that during the dry season, certain parameters exceeded acceptable limits, including temperature, total suspended solids (TSS), total dissolved solids (TDS), phosphate, and nitrate. Although there were reductions in BOD (1555mg/L to 482mg/L) and COD levels (3160mg/L to 972mg/L), they remained above acceptable limits by World Health Organization. In the wet season, the level of COD (20mg/L) in the effluent was within acceptable limit, while the BOD (160mg/L) was above the acceptable limit. The WWTP effectively removed nutrients and reduced the microbial load, as evident from the absence of fecal coliforms in the effluent in both seasons. In respect to BOD removal efficiency, the level of purification of wastewater by the WWTP was 69% during the dry season, while the removal efficiency of COD was 83.54% which showed the efficiency of the WWTP at the removal of COD. However, antibiotic resistance was still present. The study concludes that while the WWTP effectively addressed nutrients and microbial load, additional measures such as tertiary treatment methods like chlorination and UV radiation are necessary to tackle antibiotic resistance. This is crucial to prevent the release of antibiotic-resistant bacteria into the environment, safeguarding human health, animals, plants, and overall environmental well-being.