An OUR-based approach to determine the toxic effects of 2,4-dichlorophenoxyacetic acid in activated sludge

Meriç, Süreyya; Eremektar, Gülen; Çiner, Fehiman; Tünay, Olcay

doi:10.1016/s0304-3894(03)00147-x

Cited by 21 publications

(8 citation statements)

References 12 publications

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“…Biological treatments are environmentally friendly and in general less expensive than physicochemical methods for wastewater treatment (Kargi and Eker 2006), but they can be excessively slow or even unfeasible when the microbial activity is affected by the toxicity of xenobiotic compounds (Meric et al 2003;Tamer et al 2006). Thus, before performing the biological treatment of a specific wastewater, it is necessary to assess its toxicity and biodegradability (Gutiérrez et al 2002).…”

Section: Introductionmentioning

confidence: 99%

Comparison of experimental methods for determination of toxicity and biodegradability of xenobiotic compounds

et al. 2011

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Different methods for determining the toxicity and biodegradability of hazardous compounds evaluating their susceptibility to biological treatment were studied. Several compounds including chlorophenols and herbicides have been evaluated. Toxicity was analyzed in terms of EC50 and by a simple respirometric procedure based on the OECD Method 209 and by the Microtox® bioassay. The values of EC50 obtained from respirometry were in all the cases higher than those from the Microtox® test. The respirometric inhibition values of chlorophenols were related well with the number of chlorine atoms and their position in the aromatic ring. In general, herbicides showed lower inhibition, being alachlor the less toxic from this criterion. For determination of biodegradability an easier and faster alternative to the OECD Method 301, with a higher biomass to substrate ratio is proposed. When this test was negative, the Zahn-Wellens one was performed in order to evaluate the inherent biodegradability. In the fast test of biodegradability, 4-chlorocatechol and 4-chlorophenol showed a complete biodegradation by an unacclimated sludge upon 48 h. These results together with their low respirometric inhibition, allow concluding that these compounds could be conveniently removed in a WWTP. Alachlor, 2,4-dichlorophenol, 2,4,6-trichlorophenol and MCPA showed a partial biodegradation upon 28 days by the Zahn-Wellens inherent biodegradability test.

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Section: Introductionmentioning

confidence: 99%

Comparison of experimental methods for determination of toxicity and biodegradability of xenobiotic compounds

et al. 2011

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“…Because the cost of handling excess sludge is a major concern in the management of an activated sludge treatment plant, the reduction of sludge production by a xenobiotic may be a benefit for the plant when it must treat an influent containing the xenobiotic. In additional to the activated sludge's favorable xenobiotic treatment capability by which the mutagenic, carcinogenic, or toxic properties of the xenobiotics (Meric et al, 2003) are mitigated, the benefits of reduction of sludge production may enhance the efficacy for an activated sludge plant in xenobiotic treatment.…”

Section: Resultsmentioning

confidence: 99%

Xenobiotic substrate reduces yield of activated sludge in a continuous flow system

Chong

Wang

et al. 2011

Bioresource Technology

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“…Activated sludge was fed in separate mediums corresponding to different periods as follows: The first period was to cultivate activated sludge in a sequence batch reactor with supplementing daily sucrose 100mg/l, peptone 18mg/l, FeCl 3 1mg/l, NH 4 Supposing that: 0 stands for the best concentrations; "-"stands for the lower concentrations than the best concentrations; "+" stands for the higher concentrations than the best concentrations. From the supposition, the matrix of sugar and peptone concentrations is shown in Table 1.…”

Section: Experimental Methods To Obtain Acclimated Activated Sludgementioning

confidence: 99%

“…The uncoupling, or the energy-spilling reactions, occurs when catabolism energy is dissipated or diverted away from anabolism through the metabolism of a substrate in bacterial cells [1]. Although xenobiotics containing wastewater can be suitably treated using biological methods [2,3,4,5], the xenobiotic nature of the pollutant requires the treatment plant microorganisms (typically activated sludge) to go through an acclimation phase before the microorganisms evolve the degradation capability for treating the influent xenobiotics. Thus, biodegradation method is used widely to treat xenobiotics in water treatment methods.…”

Section: Introductionmentioning

confidence: 99%

Effects of combined growth of biogenic and xenobiotic substrates on degradation of xenobiotic by activated sludge

et al. 2017

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Abstract. The purpose of this study was to research about supplementation of different concentrations of the substrate on the degradation rate of xenobiotic and to determine the optimal concentrations of the auxiliary substrates that are most beneficial of xenobiotic degradation rate. 2,4-dichlorophenol acid (2,4-D) was used representative xenobiotic organic compounds, while peptone and sugar used for auxiliary substrates. The activated sludge was completely break down 100 mg/l of 2,4-D for three consecutive times. The different concentrations between biogenic substracts of sucrose and peptone were fed separately or combined into the medium containing 200 mg/l of 2,4-D and 140 mg SS/l of activated sludge. The results showed that sugar and peptone could affect 2,4-D degradation rate to several different degree at different concentrations. In separate supplementation, 2,4-D degradation completed within 25 hours, 40 mg/l sugar and 150 mg/l peptone concentrations were found to be the optimal concentrations. In combined case, 2,4-D was consumed totally within 20 hours and the optimal concentration of the combined sugar and peptone concentrations were 40 and 150 mg/l, respectively.

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An OUR-based approach to determine the toxic effects of 2,4-dichlorophenoxyacetic acid in activated sludge

Cited by 21 publications

References 12 publications

Comparison of experimental methods for determination of toxicity and biodegradability of xenobiotic compounds

Comparison of experimental methods for determination of toxicity and biodegradability of xenobiotic compounds

Xenobiotic substrate reduces yield of activated sludge in a continuous flow system

Effects of combined growth of biogenic and xenobiotic substrates on degradation of xenobiotic by activated sludge

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