COMPARISON OF CONVENTIONAL AND Vibrio fischeri BIOASSAYS FOR THE ASSESSMENT OF MUNICIPAL WASTEWATER TOXICITY

Combined treatment of landfill leachate and municipal wastewater was performed in order to investigate the changes of leachate toxicity during biological treatment. Three laboratory A2O lab-scale reactors were operating under the same parameters (Q-8.5–10 L/d; HRT-1.4–1.6 d; MLSS 1.6–2.5 g/L) except for the influent characteristic and load. The influent of reactor I consisted of municipal wastewater amended with leachate from postclosure landfill; influent of reactor II consisted of leachate collected from transient landfill and municipal wastewater; reactor III served as a control and its influent consisted of municipal wastewater only. Toxicity of raw and treated wastewater was determinted by four acute toxicity tests withDaphnia magna, Thamnocephalus platyurus, Vibrio fischeri,andRaphidocelis subcapitata. Landfill leachate increased initial toxicity of wastewater. During biological treatment, significant decline of acute toxicity was observed, but still mixture of leachate and wastewater was harmful to all tested organisms.

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Removal of Pharmaceuticals, Toxicity and Natural Fluorescence by Ozonation in Biologically Pre-Treated Municipal Wastewater, in Comparison to Subsequent Polishing Biofilm Reactors

Water ◽

10.3390/w12041059 ◽

2020 ◽

Vol 12 (4) ◽

pp. 1059

Author(s):

Kai Tang ◽

Gordon Ooi ◽

Aikaterini Spiliotopoulou ◽

Kamilla Kaarsholm ◽

Kim Sundmark ◽

...

Keyword(s):

Laboratory Experiments ◽

Municipal Wastewater ◽

Vibrio Fischeri ◽

Biofilm Reactor ◽

Wastewater Effluent ◽

Moving Bed Biofilm Reactor ◽

Biofilm Reactors ◽

Pharmaceutical Removal ◽

Natural Fluorescence ◽

Treated Municipal Wastewater

Ozonation followed by a polishing moving bed biofilm reactor (MBBR) was implemented in pilot and laboratory to remove the residual pharmaceuticals and toxicity from wastewater effluent, which was from a pilot hybrid system of MBBR and activated sludge, receiving municipal wastewater. The delivered ozone dosages achieving 90% pharmaceutical removal were determined both in pilot and laboratory experiments and they were normalised to dissolved organic carbon (DOC), illustrating our findings were comparable with previously published literature. During wastewater ozonation, the intensity of natural fluorescence was found to be greatly associated with the concentrations of the studied pharmaceuticals. In pilot experiments, toxicity, measured by Vibrio fischeri, increased after ozonation at delivered ozone dosages at 0.38–0.47 mg O3/mg DOC and was completely removed by the subsequent polishing MBBR. Laboratory experiments verified that the polishing MBBR was able to remove the toxicity produced by the ozonation.

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Bioassays and biomarkers for ecotoxicological assessment of reclaimed municipal wastewater

Water Science & Technology ◽

10.2166/wst.2008.196 ◽

2008 ◽

Vol 57 (6) ◽

pp. 947-953 ◽

Cited By ~ 6

Author(s):

A. Kontana ◽

M. Yiangou ◽

C. A. Papadimitriou ◽

P. Samaras ◽

A. Zdragas

Keyword(s):

Municipal Wastewater ◽

Vibrio Fischeri ◽

Tertiary Treatment ◽

Reclaimed Wastewater ◽

Immunological Parameters ◽

Test Species ◽

Mouse Splenocytes ◽

Microbiological Characteristics ◽

Cytokine Levels ◽

Wastewater Samples

The aim of this work was to examine the ecotoxicity of reclaimed wastewater by the use of bioassays and the determination of immunological parameters. Secondary and tertiary mucicipal wastewater samples were examined for their physicochemical and microbiological characteristics as well as for their endotoxin concentrations. The ecotoxicological characteristics were assessed by a battery of bioassays, using Vibrio fischeri, Daphnia magna and Tetrahymena thermophilla as test species and phytotoxicity. The mitogenic responses of mouse splenocytes were as well used as bioassay. The cytokines of IL-1, IL-2, IL-10, IFNγ and TNFα, were also determined in the supernatant of splenocyte cultures and served as molecular biomarkers. All bioassays exhibited decrease of the ecotoxicological responses after tertiary treatment. However, mitogenic responses were proved to be more sensitive. IL-1 increased, while IL-2 production was unaffected. The fact that IL-10 production increased in response to secondary treated effluents in conjunction with the increased endotoxin levels, suggest Th2 type immune responses. Although results obtained from the toxicity bioassays after the tertiary treatment showed comparable results to those of controls, cytokine levels indicated the induction of immune response even after tertiary treatment. Consequently, cytokine production could be used as a sensitive biomarker for the evaluation of treatment efficiency of the reclaimed wastewaters intended for reuse.

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Removal of a mixture of pharmaceuticals sulfamethoxazole and diclofenac from water streams by a polyamide nanofiltration membrane

Water Science & Technology ◽

10.2166/wst.2020.166 ◽

2020 ◽

Vol 81 (4) ◽

pp. 732-743

Author(s):

Daniela Gomes ◽

Mafalda Cardoso ◽

Rui C. Martins ◽

Rosa M. Quinta-Ferreira ◽

Lícinio M. Gando-Ferreira

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Vibrio Fischeri ◽

Applied Pressure ◽

Treatment Plant ◽

Oxygen Demand ◽

Operating Conditions ◽

Process Efficiency ◽

Secondary Effluent ◽

Municipal Wastewater Treatment

Abstract Wastewater treatment plants are not specially designed to remove pharmaceutically active compounds (PhACs), since these substances are toxic and bio-refractory. This paper aims to investigate and optimize the performance of the Trisep TS80 nanofiltration (NF) membrane for the removal of a mixture of two of the most detected PhACs in municipal wastewaters worldwide, sulfamethoxazole and diclofenac. Several NF tests were carried out to study the rejections of these contaminants both spiked in demineralized water, filtrated water taken from Mondego River and secondary effluent coming from a municipal wastewater treatment plant. Among the several studied operating variables, pH was the one that most affected the contaminant rejection and membrane permeability. In the case of synthetic effluent, an applied pressure of 10 bar and pH 7 were determined as the best operating conditions, which allowed almost total chemical oxygen demand retention and a global contaminant rejection of 96.3% to be achieved. The application of different water matrices (river water and secondary municipal effluent) had no relevant impact on process efficiency. Vibrio fischeri luminescence inhibition tests revealed that treatment by nanofiltration reduced acute toxicity of all studied effluents.

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A new disinfection system for wastewater treatment: performic acid full-scale trial evaluations

Water Science & Technology ◽

10.2166/wst.2013.137 ◽

2013 ◽

Vol 67 (11) ◽

pp. 2476-2487 ◽

Cited By ~ 17

Author(s):

P. Ragazzo ◽

N. Chiucchini ◽

V. Piccolo ◽

M. Ostoich

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Vibrio Fischeri ◽

Product Formation ◽

Full Scale ◽

Performic Acid ◽

Municipal Wastewater Treatment ◽

Faecal Coliforms ◽

E Coli

To evaluate the efficiency and effect of a new disinfection technology in wastewater treatment, batch and full-scale experiments were performed between winter 2005 and summer 2011. The system, developed by Kemira Oyj, produces a disinfection solution containing performic acid (PFA) by mixing hydrogen peroxide and formic acid. A preliminary study in batch reactors established the suitability for wastewater disinfection; three subsequent full-scale plant experiments conducted at two municipal wastewater treatment plants (120,000 and 32,000 equivalent inhabitants) discharging in sensitive areas demonstrated its effectiveness and reliability in this application field. The disinfection power of the system was measured using faecal coliforms, Escherichia coli and faecal enterococci; additional water quality parameters included total organic carbon, suspended solids, eco-toxicity and disinfection by-products. Full-scale experiments indicated that PFA has a high disinfection power, always ensuring over 3 log of faecal coliforms and E. coli reductions at CT over 60 mg/L min (CT: disinfectant initial Concentration (mg/L) × contact Time (min)). The final production system yielded even better performance, with E. coli and faecal enterococci reductions ranging from 2 to 4.2 and from 0.7 to 3.2 log, respectively, at CT conditions lower than 23 mg/L min. There were no eco-toxicological effects measured by Vibrio fischeri or by-product formation.

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