Treatment of carbofuran-bearing synthetic wastewater using UASB process.
03 Mar 2007-Journal of Environmental Science and Health Part B-pesticides Food Contaminants and Agricultural Wastes (Informa UK Limited)-Vol. 42, Iss: 2, pp 189-199
TL;DR: The toxic effect of carbofuran was reversible to a certain extent and the reactor efficiency was also measured in terms of specific acetoclastic methanogenic activity (SMA).
Abstract: In the present study, fate of carbofuran in anaerobic environments and the adverse effects of carbofuran on conventional anaerobic systems were evaluated. Carbofuran degradation studies were carried out in batch reactors with varying carbofuran concentrations of 0 to 270.73 mg/L corresponding to a sludge-loading rate (SLR) of 2.12 × 10− 6 to 3.83 × 10− 3 g of carbofuran/g of volatile suspended solids (VSS)/d. Carbofuran concentration was reduced to undetectable levels at the end of 8 and 13 days in the batch reactors operated with a SLR of 2.12 × 10− 6 and 3.33 × 10− 5 g of carbofuran/g of VSS/d, respectively. Performances of two anaerobic reactors i.e. upflow anaerobic sludge blanket (UASB) and modified UASB (with tube settlers) were evaluated in the presence and absence of carbofuran using synthetic wastewater. In the absence of carbofuran, the soluble chemical oxygen demand (COD) removal efficiency in the conventional UASB reactor at 8 h and 6 h hydraulic retention time (HRT) was nearly 88% and 76%, re...
Citations
More filters
TL;DR: The use of this consortium for the treatment of CBF and other carbamates at reactor scale represents a potential approach for the removal of these pesticides from agricultural wastewater, as an alternative to BPS.
18 citations
22 Feb 2017-Journal of Environmental Science and Health Part B-pesticides Food Contaminants and Agricultural Wastes
TL;DR: The reactor system and GAC-TiO2 catalyst used could be constructive in cost-effective CBF removal with no impact to receiving environment through getaway of photocatalyst.
Abstract: Carbofuran (CBF) removal in a continuous-flow photocatalytic reactor with granular activated carbon supported titanium dioxide (GAC-TiO2) catalyst was investigated. The effects of feed flow rate, TiO2 concentration and addition of supplementary oxidants on CBF removal were investigated. The central composite design (CCD) was used to design the experiments and to estimate the effects of feed flow rate and TiO2 concentration on CBF removal. The outcome of CCD experiments demonstrated that reactor performance was influenced mainly by feed flow rate compared to TiO2 concentration. A second-order polynomial model developed based on CCD experiments fitted the experimental data with good correlation (R2 ∼ 0.964). The addition of 1 mL min−1 hydrogen peroxide has shown complete CBF degradation and 76% chemical oxygen demand removal under the following operating conditions of CBF ∼50 mg L−1, TiO2 ∼5 mg L−1 and feed flow rate ∼82.5 mL min−1. Rate constant of the photodegradation process was also calculated b...
17 citations
TL;DR: In this article , the intracellular and extracellular metabolites of the Chryseobacterium sp. BSC2-3 strain were analyzed during carbofuran degradation by using a liquid chromatography-mass spectrometry-based metabolomics approach.
Abstract: Carbofuran is one of the most commonly used N-methylcarbamate-based pesticides and is excellent for controlling pests; however, carbofuran also causes soil and water pollution. Although various studies have been conducted on the bioremediation of pesticide-contaminated soil, the changes occurring in the metabolome during the bioremediation of carbofuran are not fully understood. In this study, the intracellular and extracellular metabolites of the Chryseobacterium sp. BSC2-3 strain were analysed during carbofuran degradation by using a liquid chromatography-mass spectrometry-based metabolomics approach. We found that the BSC2-3 strain extracellularly transformed carbofuran into 3-hydroxycarbofuran. Intracellular metabolite analysis revealed that carbofuran mainly affected aminobenzoate degradation, ubiquinone and terpenoid-quinone biosynthesis, and arginine and proline metabolism. Carbofuran especially affected the metabolic pathway for the degradation of naphthalene and aminobenzoate. Metabolomics additionally revealed that the strain produces disease resistance inducers and plant growth regulators. We also identified the genes involved in the production of indole-3-acetic acid, which is one of the most active auxins. Overall, we identified the metabolic changes induced in carbofuran-degrading bacteria and the genes predicted to be responsible for the degradation of carbofuran.
4 citations
TL;DR: In this article , a review describes carbofuran toxicity to the eye with special emphasis on corneal morbidities and blindness, and reported alteration of autophagy mechanism in human cornea in vitro and ex vivo post carbofuranium exposure.
References
More filters
Journal Article•
TL;DR: Test de mesure de l'activite methanogenique, utile pour le controle des digesteurs anaerobies as mentioned in this paper, is a test suite for the controllation of digestes.
Abstract: Test de mesure de l'activite methanogenique, utile pour le controle des digesteurs anaerobies
113 citations
"Treatment of carbofuran-bearing syn..." refers methods in this paper
...The sludge sample was first diluted to get a VSS concentration of approximately 5 g/L with a mineral solution[16] consisting of (g L−1) KH2PO4 : 2....
[...]
TL;DR: The reduction of nitrite by metallic iron was a pseudo-zero-order reaction under the experimental conditions and Neutral condition enhanced the formation of nitrogen gas from nitrite reduction.
91 citations
TL;DR: The movement of several pesticides was studied from 1985 to 1987 in a small, agricultural watershed as discussed by the authors, where the watershed contained a distinct, ephemeral stream bed and two permanent, small reservoirs The five herbicides measured − 2,4 dichlorophenoxyacetic acid (2,4 D), dicamba, bromoxynil, diclofop-methyl, and triallate were those most commonly used.
Abstract: The movement of several pesticides was studied from 1985 to 1987 in a small, agricultural watershed The watershed contained a distinct, ephemeral stream bed and two permanent, small reservoirs The five herbicides measured −2,4 dichlorophenoxyacetic acid (2,4 D), dicamba, bromoxynil, diclofop-methyl, and triallate – were those most commonly used in the watershed Of the 105 collected ground water samples 47% contained residues of one or more herbicides Residues in surface water samples were less frequent, and concentrations were lower than those in ground water All spring snowmelt runoff samples were collected in 1985 and 1987 and contained some pesticide residues The significance of these findings will be discussed and related to potential environmental toxicological effects Severe grasshopper infestations in 1985 and 1986 resulted in insecticide treatments in the study area Water samples were tested for the insecticides carbofuran, carbaryl, chlorpyrifos, dimethoate, and deltamethrin Three samples of spring runoff, collected from one site in 1987, contained approximately 1 ppb carbofuran All other samples were less than the detection levels
90 citations
TL;DR: Soil microorganisms converting heptachlor to its epoxide were identified and the presence of cyclodiene insecticides in the media appeared to influence some microbial metabolic processes.
Abstract: Chemical and soil microbial degradation of heptachlor proceeded by at least 3 pathways: epoxidation, hydrolysis, and reduction. Soil microorganisms converting heptachlor to its epoxide were identified. Thirty-five of 47 fungi, and 26 of 45 bacteria and actinomycetes isolated from soil produced the epoxide. In aqueous media, heptachlor hydrolyzed chemically to 1-hydroxychlordene, which the soil microorganisms were able to epoxidize to I-hydroxy. 2,3-epoxychlordenc. Heptachlor was dechlorinated by bacteria to chlordene which was then epoxidized to chlor dene epoxide. The insecticide and its byproducts were concentrated in the fungal mycelium. The presence of cyclodiene insecticides in the media appeared to influence some microbial metabolic processes.
72 citations
"Treatment of carbofuran-bearing syn..." refers background in this paper
...Many anaerobic pure bacterial isolates have been found to be successful in dechlorination and degradation of many recalcitrant and toxic organic substances like heptachlor,[9] chlorophenols,[10] chlorobenzene[11] and pentachloroethylene....
[...]
TL;DR: Both the test reactor and the R1 reactor showed conversion of PCE to DCE, even at HRTs much lower than the reciprocal maximum specific growth rate of D. multivorans, indicating that this bacterium was immobilized in the living and autoclaved granular sludge.
Abstract: Dechlorination of tetrachloroethene, also known as perchloroethylene (PCE), was investigated in an upflow anaerobic sludge blanket (UASB) reactor after incorporation of the strictly anaerobic, reductively dechlorinating bacterium Dehalospirillum multivorans into granular sludge. This reactor was compared to the reference 1 (R1) reactor, where the granules were autoclaved to remove all dechlorinating abilities before inoculation, and to the reference 2 (R2) reactor, containing only living granular sludge. All three reactors were fed mineral medium containing 3 to 57 μM PCE, 2 mM formate, and 0.5 mM acetate and were operated under sterile conditions. In the test reactor, an average of 93% (mole/mole) of the effluent chloroethenes was dichloroethene (DCE), compared to 99% (mole/mole) in the R1 reactor. The R2 reactor, with no inoculation, produced only trichloroethene (TCE), averaging 43% (mole/mole) of the effluent chloroethenes. No dechlorination of PCE was observed in an abiotic control consisting of sterile granules without inoculum. During continuous operation with stepwise-reduced hydraulic retention times (HRTs), both the test reactor and the R1 reactor showed conversion of PCE to DCE, even at HRTs much lower than the reciprocal maximum specific growth rate of D. multivorans, indicating that this bacterium was immobilized in the living and autoclaved granular sludge. In contrast, the R2 reactor, with no inoculation of D. multivorans, only converted PCE to TCE under the same conditions. Immobilization could be confirmed by using fluorescein-labeled antibody probes raised against D. multivorans. In granules obtained from the R1 reactor, D. multivorans grew mainly in microcolonies located in the centers of the granules, while in the test reactor, the bacterium mainly covered the surfaces of granules.
47 citations
"Treatment of carbofuran-bearing syn..." refers background in this paper
...Many anaerobic pure bacterial isolates have been found to be successful in dechlorination and degradation of many recalcitrant and toxic organic substances like heptachlor,[9] chlorophenols,[10] chlorobenzene[11] and pentachloroethylene.[12] Earlier anaerobic biotechnology was used mainly for the digestion of sludge produced by other treatment processes....
[...]