Effluent Residue Research Articles

Kinetic and thermodynamic factors controlling the dissolution of molybdate-bearing calcines during nuclear glass synthesis

As part of an ongoing program to constrain the factors affecting phase stability in nuclear waste containment glasses, the thermodynamic and kinetic factors influencing molybdenum oxide solubility in a borosilicate melt have been studied. A simplified system has been chosen to study how Mo oxide is transferred from solid effluent residues (calcines) to glass. The model calcines used are pure Na2MoO4 and a more complex mixture of Na2MoO4 and Al-bearing phases. These solid residues are mixed with a borosilicate glass frit and heat treated isothermally at temperatures in the range 700–1000 °C for times ranging from 2 min to 8 h. The mineralogy of the mixtures has been followed as a function of temperature and time using XRD and 27Al and 23Na MAS NMR spectroscopy, while the structure and composition of the amorphous phase have been studied by 11B MAS NMR and electron microprobe. The results obtained illustrate that while the dissolution of Al-rich calcines can modify the structure of the borosilicate network this does not affect either the MoO3 content of the liquid at saturation, or the characteristic time-scale required to reach saturation. In detail, the variation of the Mo content of the liquid at saturation can be described by an Arrhenian temperature dependence with an activation energy of 30 ± 5 kJ/mol and the time-scale required to reach saturation, can be described by an exponential function of time. This time-scale also shows Arrhenian temperature dependence with an activation energy of 225 ± 25 kJ/mol, a value identical within uncertainty to that associated with viscous flow. Using the experimental results, a numerical model for dissolution along variable temperature-time paths has been developed. These models indicate that for systems that are capable of complete dissolution grain-size is one of the most important parameter controlling the efficiency of the dissolution process.

Occurrence of high priority Pharmaceutical residues in hospital effluent and its treatment by Sequencing Batch Reactors

Occurrence of high priority Pharmaceutical residues in hospital effluent and its treatment by Sequencing Batch Reactors

Occurrence of antibiotic residues and antibiotic-resistant bacteria in effluents of pharmaceutical manufacturers and other sources around Hanoi, Vietnam

Pharmaceutical manufacturers in Vietnam are producing a wide variety of antibiotics for human and veterinary use. Consequently, the water discharged from those facilities can contain residues of antibiotics, which could have adverse impact on the environment. However, studies on the occurrence of antibiotics in the wastewater from pharmaceutical manufacturers in Vietnam are almost non-existent. In this study, water samples were collected at around the outlets of four pharmaceutical manufacturing plants as well as from a hospital and an aquaculture farm around Hanoi in 2016 and 2017. Fifteen antibiotics from four major classes (β-lactam, quinolones, macrolides, sulfonamides) were monitored, using a validated LC-MS/MS method, based on their number of registrations at the Ministry of Health. Ten antibiotics, ampicillin, cefuroxime, cefotaxime, clarithromycin, azithromycin, sulfamethoxazole, trimethoprim, ofloxacin, norfloxacin, and ciprofloxacin were detected in the samples at different concentrations. Notably, sulfonamides and quinolones were occasionally detected at very high concentration, such as sulfamethoxazole (252 μg/L), trimethoprim (107 μg/L), ofloxacin (85 μg/L), and ciprofloxacin (41 μg/L). In this study, concentrations of antibiotic residues in effluent of pharmaceutical plants were higher than those from other sources. The antibiotic-resistance tests indicated the widespread resistance to common antibiotics like quinolone and sulfonamides in the collected samples. This finding suggests that wastewater from pharmaceutical manufacturers could be an important source of antibiotics and antibiotic-resistant bacteria in the aquatic environment of Vietnam.

Deriving a water quality guideline for protection of aquatic communities exposed to triclosan in the Canadian environment.

Triclosan is an antibacterial and antifungal chemical used in a variety of consumer products, including soaps, detergents, moisturizers, and cosmetics. Aquatic ecosystems may be exposed to triclosan following the release of remaining residues in wastewater effluents and biosolids. In December 2017, Environment and Climate Change Canada (ECCC) released a federal environmental quality guideline (FEQG) report that contained a federal water quality guideline (FWQG) for triclosan. This guideline will be used as an adjunct to the risk assessment and risk management of priority chemicals identified under the Government of Canada's Chemicals Management Plan (CMP). The FWQG value for triclosan (0.47 μg/L) was derived by ECCC using a hazardous concentration for 5% of species (HC5) from a species sensitivity distribution (SSD). We recalculated the FWQG after performing an independent analysis and evaluation of the available aquatic toxicity data for triclosan and compared our results with the ECCC FWQG value. Our independent analysis of the available aquatic toxicity data entailed conducting a literature search of all available and relevant studies, evaluating the quality and reliability of all studies considered using thorough and consistent study evaluation criteria, and thereby generating a data set of high-quality toxicity values. The selected data set includes 22 species spanning 5 taxonomic groups. An SSD was developed using this data set following the ECCC approaches. The HC5 from the SSD derived based on our validated data set is 0.76 μg/L. This HC5 value is slightly greater (i.e., less sensitive) than the value presented in ECCC's final FWQG. Integr Environ Assess Manag 2018;14:437-441. © 2018 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Cotton swabs supported in-situ assay for quaternary ammonium compounds residues in effluents and surfaces

Cellulose paper and cotton swabs have been tested as sampling, reaction and measurement media for quaternary ammonium compounds (QACs) using the reagent Chromo Azurol S in the presence of aluminum cations (CAS-Al). On the basis of the results obtained a new method is proposed for the analysis of QACs in water samples which only entails the successive immersion of swabs into 1 mL of the samples, 1 mL of a solution of CAS-Al for the formation of a ternary blue complex, and 1 mL of water to remove the excess of reagent. The method can be used for the visual on site detection of QACs in effluents, as well as for their quantification within the 3.62–36.2 mg/L range through the direct measurement of the reflectance diffuse of the cotton tips. The proposed approach has been validated for the identification and quantification of QACs in water, and applied to effluents generated by the dairy industry. Moreover, the proposed methodology can be also adapted to the on-site detection of residues of QACs in surfaces at sub μg/cm2 levels.

GABAergic anxiolytic drug in water increases migration behaviour in salmon

Migration is an important life-history event in a wide range of taxa, yet many migrations are influenced by anthropogenic change. Although migration dynamics are extensively studied, the potential effects of environmental contaminants on migratory physiology are poorly understood. In this study we show that an anxiolytic drug in water can promote downward migratory behaviour of Atlantic salmon (Salmo salar) in both laboratory setting and in a natural river tributary. Exposing salmon smolt to a dilute concentration of a GABAA receptor agonist (oxazepam) increased migration intensity compared with untreated smolt. These results implicate that salmon migration may be affected by human-induced changes in water chemical properties, such as acidification and pharmaceutical residues in wastewater effluent, via alterations in the GABAA receptor function.

Popular pharmaceutical residues in hospital wastewater: quantification and qualification of degradation products by mass spectroscopy after treatment with membrane bioreactor.

The occurrence of drugs in wastewater has been considered an imminent risk to the population, for the treatments used are usually ineffective. The presence of four popular drug residues (metformin, paracetamol, tetracycline, and enalapril) in hospital effluents, by using ultra-fast liquid chromatography tandem mass spectrometry (UFLC-MS/MS) with electrospray (ESI) ionization, and removal/degradation by membrane bioreactor (MBR) system are investigated in this study. For analysis method, all standard calibration curves showed satisfactory linearity (R (2) ≥ 0.993) within a relatively wide range. The recovery was between 70.4 and 105.0%, and the relative standard deviation (RSD) values were within the ranges of 8.2 and 13.5%. The effluent samples were collected at the end of the process treated in a bench-scale MBR treatment system and preconcentrated on solid-phase extraction (SPE) cartridges. Following that procedure, the chemical analysis demonstrated that the MBR system was effective in enalapril 94.3 ± 7.63%, tetracycline 99.4 ± 0.02%, and paracetamol 98.8 ± 0.86% removal. However, the polar metformin was less effectively removed (35.4 ± 12.49%). Moreover, the degradation products were investigated using high-resolution mass spectrometry (HRMS) by quadrupole-time of flight (Q-TOF), which has been indicated a tetracycline metabolite. In order to investigate the environmental impact, the wastewater potential risk was evaluated. The risk quotient (RQ) by measure environmental concentration (MEC) and its predicted no effect concentration (PNEC) ratio (RQ = MEC/PNEC) was between 0.003 (enalapril) to 0.815 (paracetamol). Finally, this work demonstrates that UFLC-MS/MS (ESI-Q) is a sensitive and selective method for drug analysis in wastewater and with ESI-Q-TOF has the accuracy required for determining the degradation products of these compounds. Also, it indicated that membrane bioreactor systems represent a new generation of processes that have proved to outperform conventional treatment showing better effluent quality. The removal capacity studied in this work demonstrates the efficiency of this process.

Effect on Particle Size of Agro based Coagulant for Treatment of Textile Mill Effluent

An experimental investigation was carried out for the feasible use of agro based coagulants of different particle size to the treatment of textile mill effluent. Coagulation-flocculation and sedimentation process were applied for the treatment of textile mill effluents using crude water extracts of dry Moringaoleifera (MO), Tamarinaindica (TI) and Strychonomous Potatorum (SP) as primary agro based coagulant. The experiments were conducted at assorted particle sizes of 90 μ, 150 μ, 300 μ, 425 μ, 600 μ and850 μ of the coagulant powders of Moringaoleifera, TamarinaIndica and Strychonomous Potatorum using jar-test experiment. The pre and post treatment of textile mill effluent with agro based coagulant of different particle size and the removal efficiency of turbidity, TDS, TSS, BOD and COD of textile mill effluent were evaluated and compared with conventional coagulant Alum (AL). The surface characteristics of M. oleifera, T. indica, S. potatorum and textile mill effluent residues of pre and post treatment were analyzed with Scanning Electron Microscope (SEM). The outcome of this paper reveals that300 μ particle sizes of Moringaoleifera were efficient in removing turbidity, TDS, TSS, BOD and COD of textile effluent at different dosages of coagulants. Consequently natural coagulant of different particle sizes gives better removal efficiencies when compared with the conventional coagulant Alum.

16SrRNA sequencing of Dye decolorizing bacteria isolated from Soil.

Dye׳s residues in textile effluents are hazardous for humans and animals health. Such pollutants can be degraded into non-harmful molecules using biological approaches that are considered cheaper and ecologically safer. Isolated 15 bacterial cultures from soil that could be used in biological system were showed decolorization capacity for Acid Green dye (33.9% to 94.0%) using thin layer chromatography and broth culture method. The most promising cultures (AMC3) to decolorize Acid green Dye (94.6%) was re-coded as NSDSUAM for submitting at IMTECH, Chandigarh for sequencing. The 16SrRNA sequencing suggested that it can be a variant of Pseudomonas geniculata (99.85% identical similarity) with difference of 2 base pairs to reference strain Pseudomonas geniculata ATCC 19374(T). Thus present study proposed dye decolorizing efficiency of the isolated strain of Pseudomonas geniculata that was previously unnoticed. The sequence is deposited in NCBI GenBank with the accession number KP238100.

Model development with defined biological mechanisms for xenobiotic treatment activated sludge at steady state.

Activated sludge treatment of a xenobiotic organic compound, much different from treatment of biogenic organics, must be modeled with interactions involving a two-part biomass of degrader and nondegrader, which selectively or competitively grow on a two-part substrate of input xenobiotic and its biogenic metabolites. A xenobiotic treatment model was developed which incorporates kinetics of the growth of degrader and nondegrader, the line dividing metabolites into xenobiotic and biogenic, yields of degrader and nondegrader from utilization of their parts of substrates, and kinetics of degrader reversion to nondegrader due to instability of the degradative element degraders carry. Experimental activated sludge operated for treatment of a xenobiotic generated data for calibration of the model. With the input of influent xenobiotic concentration, mean cell and hydraulic residence times, and calibrated parameters, the model readily outputs concentrations of degrader, nondegrader, and effluent biogenic residue that closely match the results obtained from experiments.

Multi-residue analytical methodology-based liquid chromatography-time-of-flight-mass spectrometry for the analysis of pharmaceutical residues in surface water and effluents from sewage treatment plants and hospitals

An analytical method that facilitated the analysis of 11 pharmaceuticals residue (caffeine, prazosin, enalapril, carbamazepine, nifedipine, levonorgestrel, simvastatin, hydrochlorothiazide, gliclazide, diclofenac-Na, and mefenamic acid) with a single pre-treatment protocol was developed. The proposed method included an isolation and concentration procedure using solid phase extraction (Oasis HLB), a separation step using high-performance liquid chromatography, and a detection procedure that applies time-of-flight mass spectrometry. The method was validated for drinking water (DW), surface water (SW), sewage treatment plant (STP) influent and effluent, and hospital (HSP) influent and effluent. The limits of quantification were as low as 0.4, 1.6, 5, 3, 2.2 and 11ng/L in DW, SW, HSP influent and effluent, STP effluent, and STP influent, respectively. On average, good recoveries higher than 75% were obtained for most of the target analytes in all matrices. Matrix effect was evaluated for all samples matrices. The proposed method successfully determined and quantified the target compounds in raw and treated wastewater of four STPs and three hospitals in Malaysia, as well as in two SW sites. The results showed that a number of the studied compounds pose moderate to high persistency in sewage treatment effluents as well as in the recipient rivers, namely; caffeine, simvastatin, and hydrochlorothiazide. Ten out of 11 compounds were detected and quantified in 13 sampling points. Caffeine was detected with the highest level, with concentrations reaching up to 9099ng/L in STP influent.

A year-long study of the spatial occurrence and relative distribution of pharmaceutical residues in sewage effluent, receiving marine waters and marine bivalves

Reports concerning the quantitative analysis of pharmaceuticals in marine ecosystems are somewhat limited. It is necessary to determine pharmaceutical fate and assess any potential risk of exposure to aquatic species and ultimately, seafood consumers. In the work presented herein, analytical methods were optimised and validated for the quantification of pharmaceutical residues in wastewater effluent, receiving marine waters and marine mussels (Mytilus spp.). Selected pharmaceuticals included two non-steroidal anti-inflammatory drugs (NSAIDs) (diclofenac and mefenamic acid), an antibiotic (trimethoprim), an antiepileptic (carbamazepine) and a lipid regulator (gemfibrozil). This paper also presents the results of an in situ study in which caged Mytilus spp. were deployed at three sites on the Irish coastline over a 1-year period. In water samples, pharmaceutical residues were determined using solid phase extraction (SPE) and liquid chromatography–tandem mass spectrometry (LC–MS/MS). The extraction of pharmaceuticals from mussel tissues used an additional pressurised liquid extraction (PLE) step prior to SPE and LC–MS/MS. Limits of quantification between 15 and 225ng·L−1 were achieved in wastewater effluent, between 3 and 38ng·L−1 in marine surface water and between 4 and 29ng·g−1 dry weight in marine mussels. Method linearity was achieved for pharmaceuticals in each matrix with correlation coefficients of R2≥0.976. All five selected pharmaceuticals were quantified in wastewater effluent and marine surface waters. This work has demonstrated the susceptibility of the Mytilus spp. to pharmaceutical exposure following the detection of pharmaceutical residues in the tissues of this mussel species at measurable concentrations.

Improvement of a three-step process for the treatment of aluminium hazardous wastes containing PAHs (benzo[b,j,k]fluoranthene and chrysene) and fluoride

Hazardous wastes from a primary aluminium production plant could be decontaminated by a three-step process. First, the PAHs contained in these wastes were extracted with an amphoteric surfactant (0.25% or 0.50% w/w of cocamidopropylhydroxysultaine [CAS]) by cell or column flotation, depending on the particle size fraction (under or above 500 μm). Then, the fluorides were stabilized with lime (8% w/w) or a mixture of lime (4% w/w) and phosphoric acid (0.95% w/w). The decontaminated wastes satisfied the Quebec PAH norm, fixed at 1000 mg kg−1, with values of 900±352 mg kg−1 and 624±179 mg kg−1 for benzo(b,j,k)fluoranthene (BJK) at laboratory and pilot scales, respectively. The fluoride stabilization in the treated wastes was characterized by TCLP values of 138±67 mg F− L−1 and 29.5±7.6 mg F− L−1 for laboratory and pilot experiments, which were under the Quebec norm (<150 mg F− L−1). Finally, the metals in the process effluent were recovered by precipitation with sulphuric acid (10% v/v), and the final effluent and metallic residue obtained were recirculated without liquid fraction enrichment impact. The whole process was successfully tested at pilot scale. The preliminary economic study showed the potential of the process for the treatment of aluminium hazardous wastes.

Identification of biotransformation products of macrolide and fluoroquinolone antimicrobials in membrane bioreactor treatment by ultrahigh-performance liquid chromatography/quadrupole time-of-flight mass spectrometry

Ultrahigh-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry was applied for the identification of transformation products (TPs) of fluoroquinolone (norfloxacin and ciprofloxacin) and macrolide (azithromycin, erythromycin, and roxitromycin) antimicrobials in wastewater effluents from a Zenon hollow-fiber membrane bioreactor (MBR). The detected TPs were thoroughly characterized using the accurate mass feature for the determination of the tentative molecular formulae and MS-MS experiments for the structural elucidation of unknowns. Several novel TPs, which have not been previously reported in the literature, were identified. The TPs of azithromycin and roxithromycin, identified in MBR effluent, were conjugate compounds, which were formed by phosphorylation of desosamine moiety. Transformation of fluoroquinolones yielded two types of products: conjugates, formed by succinylation of the piperazine ring, and smaller metabolites, formed by an oxidative break-up of piperazine moiety to form the 7-[(2-carboxymethyl)amino] group. A semi-quantitative assessment of these TPs suggested that they might have contributed significantly to the overall balance of antimicrobial residues in MBR effluents and thus to the overall removal efficiency. Determination of TPs during a period of 2 months indicated a conspicuous dynamics, which warrants further research to identify microorganisms involved and treatment conditions leading to their formation.

Levels of pesticide residues in irrigation effluent from tomato fields in Owiro Estate, Tanzania

Pesticide residues lindane, chlorpyrifos and endosulfan sulphate were detected in water from the spring source, within field and return channel of vegetable farms in Ngarenanyuki, Tanzania. Extraction of the pesticide residues were conducted by liquid-liquid extraction (LLE) method. The detection and concentrations of pesticide residues were determined by gas chromatography equipped with electron capture detector (GCECD). The percentage detections in return channel and within field were observed to be 67 and 33 respectively whereas no pesticides were detected in the spring source. The average concentrations for lindane, chlorpyrifos and endosulfan sulphate within field and return channel were 3.0, 0.27 and 3.35, and 2.8, 0.06 and 3.13 mg/L, respectively. Absence of residues detection in spring source indicates that the source of pesticides in water from the field and return channel were the applications of pesticides in vegetable farms. This work, thus, seeks to provide information on levels of pesticide residues in water that will assist in a scientific assessment of the impact of pesticides application on public health and ecosystem in Tanzania.Keywords: Organochlorines, Organophosphorous, Water contamination, Ngarenanyuki.

INDUSTRY ISSUES: Pharmaceutical Factories as a Source of Drugs in Water

INDUSTRY ISSUES: Pharmaceutical Factories as a Source of Drugs in Water

An investigation into the behaviour of concrete containing seawater-neutralised bauxite refinery residues in silage effluent

The farm production of silage as a winter-feed supplement is widespread. However, the bins in which silage is produced are subject to acidic and microbial attacks. Both these types of attack can lead to a weakening and failure of the concretes, especially on the outer lip of the open side of the silage pit. Consequently, the development of an acid-resistant concrete that can extend the life span of silage bins on farms could lead to considerable cost savings for farmers and, hence, can improve farm productivity. This paper reports on test results of an investigation into the behaviour of concrete containing seawater-neutralised bauxite refinery residues (Bauxsol™) exposed to sulphuric acid environments in the laboratory and to silage effluents. The concrete manufactured had a fixed water–cement ratio of 0.55 and natural sand was replaced with the Bauxsol™ at 0%, 5%, 10%, 15% and 20% by cement mass. Results indicated that the use of Bauxsol™ as a sand replacement material improved the behaviour of concrete both in sulphuric acid in the laboratory as well as in the silage effluent. Consequently, it is concluded that the Bauxsol™ can be used to replace 10% of natural sand to produce concrete that is resistant to silage effluents, providing an extended service life over conventional concretes used in silage pits.

Degradation of pesticide residues in vineyard effluents by activated sludge treatment

The study evaluates the feasibility of the degradation of thirteen pesticides by an activated sludge aerobic treatment, used for the purification of wastewater effluents produced from a winemaking process. Chemical analyses were used to determine the capacity of the treatment to eliminate the implied pollution hazard. The results show that the biological treatment of such pesticides by activated sludge is possible if a minimum adaptation period of approximately 8 days is applied. System stability is reached in 30 days. The related degradation of twelve pesticides was 97%, the exception being anilinopyrimidin. However, the sludge biomass is dispersed (the pesticides destroyed the biomass flocs) and it was necessary to add a flocculation stage to concentrate and remove the free micro-organisms by using sedimentation.

Avaliação da contaminação do Igarapé do Sabino (Bacia do Rio Tibiri) por metais pesados, originados dos resíduos e efluentes do Aterro da Ribeira, em São Luís, Maranhão

This work aimed to carry out an environmental monitoring in sabino narrow river (affluent of Tibiri Basin, in Sao Luis - MA, Brazil), in order to verify the main environmental impacts caused by effluent residues from Ribeira landfill. Chemical analysis and bibliographic and cartographic researches on this ecosystem were also carried out. In addition, heavy metals, such as Hg, Pb and Zn, were investigated in water samples by ICP-MS technique. It was observed that the contents of such heavy metals were above the tolerance limits established by the Brazilian legislation, showing a strong impact level on the evaluated ecosystem.

A combination of statistical and analytical evaluation methods as a new optimization strategy for the quantification of pharmaceutical residues in sewage effluent

In this study, a new solid-phase microextraction (SPME) method for simultaneous extraction of pharmaceutical compounds with acidic and basic characteristics (ibuprofen, fenoprofen, diclofenac, diazepam and loratadine) from residual water samples is proposed. In this procedure, the extraction is processed using two distinct sample pH values. The extraction is begun at pH 2.5 to promote the sorption of acidic pharmaceuticals and after 35 min the sample pH is changed to 7.0 by adding 0.4 mol L −1 disodium hydrogenphosphate, so that the basic compounds can be sorbed by the fiber (20 min). The pH change is performed without interruption of the extraction process. A comparison between the proposed method and the SPME method applied to each group of the target compounds was performed. Gas chromatography coupled to mass spectrometry was used for separation and detection of analytes. The extraction conditions for the three methods were optimized using full factorial experimental design, response surface through a Doehlert matrix and central composite design. Limits of detection (0.02–0.43 μg L −1) and correlation coefficients (0.9970–0.9998) were determined for the three methods. The proposed extraction procedure was applied to samples of sewage treatment plant effluent and untreated wastewater. Recovery and relative standard deviation values ranged from 67 to 116% and 4.6 to 14.5%, respectively, for all compounds studied. Modification of sample pH during the extraction procedure was shown to be an excellent option for all of the compounds and may be extended to the simultaneous extraction of other compounds with different acid-base characteristics.