Occurrence and removal of pharmaceuticals, hormones, personal care products, and endocrine disrupters in a full scale water reclamation plant.
This study provided the first comprehensive data on the occurrence and removal of twenty five target emerging contaminants (ECs) in a full scale water reclamation plant (WRP) in the Southeast Asian region. Nineteen out of the twenty five ECs were ubiquitously detected in raw influent samples. Concentrations of the detected ECs in raw influent samples ranged substantially from 44.3 to 124,966ng/L, depending upon the compound and sampling date. The elimination of ECs in full scale conventional activated sludge (CAS) and membrane bioreactor (MBR) systems at a local WRP was evaluated and compared. Several ECs, such as acetaminophen, atenolol, fenoprofen, indomethacin, ibuprofen, and oxybenzone, exhibited excellent removal efficiencies >90% in biological wastewater treatment processes, while some of the investigated compounds (carbamazepine, crotamiton, diclofenac, and iopamidol) appeared to be persistent in the both CAS and MBR systems. Field based monitoring results showed that MBR outperformed CAS in the elimination of most target ECs. The relationship between molecular characteristics of ECs (i.e. physicochemical properties and structural features) and their removal efficiencies during biological wastewater treatment was also elucidated. Excellent removal efficiencies >90% were often noted for ECs with the sole presence of electron donating groups (i.e. phenolic [OH] amine [NH2] methoxy [OCH3] phenoxy [OC6H5] or alkyl groups) Conversely, ECs with the absence of electron donating groups or the predominance of strong electron withdrawing groups (e.g. halogenated, carbonyl, carboxyl, and sulfonamide) tended to show poor removal efficiencies <30% in biological wastewater treatment processes.
The Science of the total environment