| dc.description.abstract | Urban wastewater treatment plants (UWTPs) could be an emission source of bioaerosols and particle matters into the air through the air-liquid exchange process and
bubble-jet-droplet mechanism. It poses the potential of spreading human opportunistic pathogen and pharmaceutical emerging pollutants in wastewater into the air. In view of the potentials of emission and exposure risks of airborne particles in UWTPs, there is a need to comprehensively characterize the physical, biological and chemical characteristics of particles emitted from UWTPs. The main objective of this study is to characterize the
wide-size-range particle size distribution (PSD) and the characteristics of bio-aerosols generated in a UWTP. In addition, the ultraviolet aerodynamic particle sizer (UV-APS; model 3314; TSI, USA) was used to detect viable bio-aerosols in real time. Meanwhile, the air samples were also collected by high-volume samplers (HV-RW; model 080130-1203; SIBATA, Japan) for investigating the occurrence and the distribution of emerging
pollutants on the particles emitted from the aeration tank.
The measurements were conducted at two sampling ports in a UWTP located in northern Taiwan. One is 1 meter away from aeration tank (AM), and the other is close to the water surface of the tank (CAT). On the number-based, the full particle size distribution exhibits a unimodal distribution and dominated by nanoparticles, which is
accounted for about 99% of the whole PSD. On the volume-based, the distribution exhibits dual peaks and the modes of particle size are located at 0.5-0.7 μm and 2-3 μm. For the results of the biological characteristics revealed by UV-APS, the peaks of the fluorescent signal were sitting around 2-3 μm, implying that the most of fluorescence particles may be bacteria aggregates or fungal species. In addition, the concentration of the bio-aerosols in the UWTPs may be underestimated by the traditional cultivating method. Moreover, pharmaceuticals and emerging pollutants can also be transferred into the air. Nine common emerging contaminants, including PFOS, Benzotriazole, Tolyltriazole, Pentoxifylline, Erythromycin-H2O, Clarithromycin, Ketamine, Methamphetamine, PFOA were analyzed and found in both air and water samples. Among them, the most abundant
chemicals in the air are Erythromycin-H2O (191.45 pg/m3) and Methamphetamine (39.02 pg/m3) and mainly reside on PM1.0. | en_US |