Volatility, Effective Density and Oxidative Potential of Aerosol Particles in The Urban Area In recent years, the toxicological mechanisms of PM-related health effects are thought to involve the generation of reactive oxygen species (ROS) derived from particulate matter (PM), since it could induce oxidative stress and cause cellular damages. Oxidative potential (OP), defined as a measure of the capacity of particles to oxidize target molecules, can be viewed as the ability to generate ROS. Thus, OP is generally used as an indicator to quantify the potential toxicity of PM and to study the correlation between PM’s physiochemical characteristics and human health. Volatility, effective density and OP are intercorrelated and dynamically evolving with time in the ambient environment. However, these aerosol properties have not been examined simultaneously in a roadside environment with a significant fraction of motorcycles in the vehicle fleet as is typical of Southeast Asia. To explore the volatility, oxidation potential, and effective density of aerosol particles, a monitoring station was established and located at the Graduate Institute of Environmental Engineering, National Taiwan University (25.02 oN, 121.54 oE), Taipei, Taiwan. It is adjacent to the main street and right at the crossing interception.

Physical, Chemical and Biological Characteristics of Aerosol Particle Emitted from an Urban Wastewater Treatment Plant Nowadays, Waste Water Treatment Plant (WWTP) is a crucial facility of maintaining the quality of natural water resources, and it is increasingly important for developing alternative urban water sources through reuse practice. However, through discharging, mixing, aerating, and spraying of sewage, significant amounts of bioaerosols and particulate matters can be produced during the wastewater treatment process and pose a high health risk to workers[1]. The risks associated with exposure to emissions from WWTPs should call for more research, stronger regulatory frameworks and safer design consideration. Secondly, in response to the presence of antibiotics in the wastewater, the bacterial generation could be stimulated to evolve with antibiotic resistance genes (ARGs). Although antibiotic resistance bacteria (ARB) and ARG have been found in the water sampled in WWTPs, only few researches on exploring the ARG and ARB in air samples. This work expose that the potential risk of inhalation exposure of emerging contaminants (solely PM1.0) and bio-aerosols (mostly in PM2.5-10) in the WWTPs should not be neglected, and these effects certainly merit urgent investigations. Reference : [1]. Hsiao et al. 2020