title: Biodegradation of four phthalate esters in sludge.
abstract: This study investigated the effects of ultrasonic pretreatment and various treatments on the aerobic degradation of four phthalic acid esters (PAEs) such as diethyl phthalate (DEP), benzyl butyl phthalate (BBP), di-n-butyl phthalate (DBP) and di-(2-ethyl hexyl)phthalate (DEHP) in sludge. The effect on PAE degradation of treating sludge with a 20 min sonication period at a power level of 0.1 W ml(-1) was evaluated. The degradation rates of the four PAEs were DBP>BBP>DEP>DEHP. Degradation rate constants (k(1)) and half-lives (t(1/2)) for the four PAEs (50 mg kg(-1)) ranged from 0.182 to 0.379 day(-1) and 1.8 to 3.8 days, respectively. The optimal pH for PAE degradation in sludge was 7.0 at 30 degrees C. PAE degradation was enhanced by the addition of yeast extract, brij 30 or brij 35 and inhibited by the addition of hydrogen peroxide. Our results show that a combination of ultrasonic pretreatment and biodegradation can effectively remove PAE from sludge.
authors.affiliation: Department of Microbiology, Soochow University, Taipei, Taiwan.
authors.forename: B V
authors.initials: BV
authors.lastname: Chang
authors.forename: T H
authors.initials: TH
authors.lastname: Wang
authors.forename: S Y
authors.initials: SY
authors.lastname: Yuan
mesh_terms: D001673:Biodegradation, Environmental; D003993:Dibutyl Phthalate / Q000737:chemistry / Q000378:metabolism; D004051:Diethylhexyl Phthalate / Q000737:chemistry / Q000378:metabolism; D004784:Environmental Monitoring; D004785:Environmental Pollutants; D007700:Kinetics; D015394:Molecular Structure; D010795:Phthalic Acids / Q000737:chemistry / Q000378:metabolism*; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology; D013010:Sonication; D013997:Time Factors
chemical_list: D004785:Environmental Pollutants; D010795:Phthalic Acids; D012722:Sewage; D003993:Dibutyl Phthalate; D004051:Diethylhexyl Phthalate; C007379:diethyl phthalate; C027561:butylbenzyl phthalate