title: A comparative study of occurrence and fate of endocrine disruptors: diethyl phthalate and dibutyl phthalate in ASP- and SBR-based wastewater treatment plants.
abstract: Phthalates are endocrine-disrupting chemicals which affect endocrine system by bio-accumulation in aquatic organisms and produce adverse health effects in aquatic organisms as well as human beings, when come in contact. Present study focuses on occurrence and removal of two phthalates: diethylphthalate (DEP) and dibutylphthalate (DBP) in two full-scale wastewater treatment plants (WWTPs) i.e. sewage treatment plants (STPs) based on well-adopted technologies, activated sludge process (ASP) and sequencing batch reactor (SBR).Gas chromatography-mass spectrometry (GC-MS) analysis was performed for both wastewater and sludge sample for determination and identification of the concentration of these compounds in both STPs by monitoring the STPs for 9 months. It was observed that the concentration of DEP was less than DBP in the influent of ASP and SBR. Average concentrations of DEP and DBP in sludge sample of ASP were found to be 2.15 and 2.08 ng/g, whereas in SBR plant, these values were observed as 1.71 and 2.01 ng/g, respectively. Concerning the removal efficiency of DEP, SBR and ASP plants were found effective with removal efficiency of 91.51 and 91.03 %, respectively. However, in the case of DBP, SBR showed lower removal efficiency (85.42 %) as compared to ASP (92.67 %). Comparative study of both plants proposed that in ASP plant, DBP reduction was higher than the SBR. Fourier transformation infrared (FTIR) analysis also confirmed the same result of sludge analysis for both STPs. Sludge disposal studied with scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and thermo-gravimetric analysis (TGA) techniques confirmed that sludge of both STPs have high calorific value and can be used as fuel to make fuel-briquettes and bottom ash to make firebricks.
authors.affiliation: Department of Civil Engineering, Indian Institute of Technology, Roorkee, 247667, India. gitaprvn@gmail.com.
authors.forename: Gita
authors.initials: G
authors.lastname: Saini
authors.affiliation: S. D. Degree College, Roorkee, Uttarakhand, 246174, India.
authors.forename: Shalini
authors.initials: S
authors.lastname: Pant
authors.affiliation: Department of Civil Engineering, Indian Institute of Technology, Roorkee, 247667, India.
authors.forename: Shri Om
authors.initials: SO
authors.lastname: Singh
authors.affiliation: Department of Civil Engineering, Indian Institute of Technology, Roorkee, 247667, India.
authors.forename: A A
authors.initials: AA
authors.lastname: Kazmi
authors.affiliation: D. A. V. P. G. College, Roorkee, Uttarakhand, 246174, India.
authors.forename: Tanveer
authors.initials: T
authors.lastname: Alam
mesh_terms: D003993:Dibutyl Phthalate / Q000032:analysis*; D052244:Endocrine Disruptors / Q000032:analysis*; D004784:Environmental Monitoring; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D010795:Phthalic Acids / Q000032:analysis*; D012722:Sewage / Q000032:analysis*; D062065:Wastewater / Q000737:chemistry
chemical_list: D003993:Dibutyl Phthalate; D052244:Endocrine Disruptors; D010795:Phthalic Acids; D012722:Sewage; D062065:Wastewater; C032279:phthalic acid; C007379:diethyl phthalate
keywords: Activated sludge process; Dibutylphthalate; Diethylphthalate; Endocrine-disrupting compounds (EDCs); GC–MS analysis; Sequencing batch reactor; TGA analysis