title: Effect of ultrasonication and Fenton oxidation on biodegradation of bis(2-ethylhexyl) phthalate (DEHP) in wastewater sludge.
abstract: The presence of bis(2-ethylhexyl) phthalate (DEHP) and its metabolites, i.e. 2-ethylhexanol, 2-ethylhexanal, and 2-ethylhexanoic acid in wastewater sludge (WWS) were investigated during aerobic digestion and Bacillus thuringiensis (Bt)-based fermentation of WWS. Ultrasonication and Fenton oxidation pre-treatment was applied to improve biodegradability of WWS and bioavailability of the target compounds for digestion and fermentation. DEHP and 2-ethylhexanoic acid were observed at higher concentration, meanwhile 2-ethylhexanol and 2-ethylhexanal were observed at lower concentration in WWS. After 20-day aerobic digestion, DEHP removal was 72%, 89%, and 85%, and 2-ethylhexanoic acid removal was 71%, 84%, 79%, respectively for raw, ultrasonicated, and Fenton-oxidized sludges. Bt was found to degrade DEHP, leading to DEHP removal of 21%, 40%, and 30%, respectively for raw, ultrasonicated, and Fenton-oxidized sludges in the fermentation. The results suggested that aerobic stabilization and Bt-based fermentation can remove the phthalates, and pre-treatment of WWS was also effective in improvement of DEHP biodegradation. Hence, Bt-based biopesticide production from WWS can be applied safely when taking into consideration the phthalate contaminants.
authors.affiliation: INRS-ETE, Université du Québec, 490 rue de la Couronne, Québec, Canada G1K 9A9.
authors.forename: T T H
authors.initials: TT
authors.lastname: Pham
authors.forename: R D
authors.initials: RD
authors.lastname: Tyagi
authors.forename: S K
authors.initials: SK
authors.lastname: Brar
authors.forename: R Y
authors.initials: RY
authors.lastname: Surampalli
mesh_terms: D000332:Aerobiosis; D001413:Bacillus thuringiensis / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002849:Chromatography, Gas; D004051:Diethylhexyl Phthalate / Q000737:chemistry / Q000378:metabolism*; D005285:Fermentation; D019220:High-Energy Shock Waves; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism*
chemical_list: C045076:Fenton's reagent; D012722:Sewage; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; D004051:Diethylhexyl Phthalate; D007501:Iron