Advanced Water Management Centre

AWMC Seminar Program: Jiexie Zhong & Ji Lu

M.Phil. student Jiexi Zhong will give his first year confirmation presentation and PhD student Ji Lu will present his mid-candidature review presentation for the AWMC seminar.

Understanding the Fate and Removal of Pharmaceuticals and Personal Care Products in Novel Wastewater Treatment Processes (Jiexi Zhong)

Abstract: The intensive use of pharmaceutical and personal care products (PPCPs) for personal health or cosmetic reasons or agricultural purposes results in the continuous release of PPCPs into the environment, posing threats to ecological environment and human health. Wastewater treatment plants (WWTPs) have been identified as one of important hotspots of PPCPs in the environment. The understanding of the fate of PPCP in WWTPs is prerequisite to develop efficient control strategies to eliminate the adverse effects of PPCPs. However, there is a lack of a comprehensive investigation about the fate of PPCPs across different treatment processes (e.g. anaerobic treatment, aerobic treatment, sedimentation, or disinfection) in WWTPs. In addition, more and more WWTPs are expected to be upgraded from conventional activated sludge (CAS) processes to novel treatment processes (such as Anammox- or MBR-based processes) to save energy consumption and reduce operational cost. Yet there is still a scarcity in literature regarding to a thorough study of PPCPs in these novel processes so far. This project aims to investigate the occurrence, fate and removal mechanisms of more than 30 selected PPCPs in both traditional and novel treatment processes by collect both liquid and solid samples from two full-scale CAS-based plants and two pilot plants employing novel processes. Although biological wastewater treatment processes could achieve PPCP removals, PPCPs may not be fully eliminated even with the development of novel biological treatment techniques, since PPCPs include a diverse array of compounds with persistent properties and some of them are not biodegradable. More importantly, this project will develop a photocatalysis process by employing nanomaterial graphitic-C3N4 as a photocatalyst. It is expected that this project outcome will enhance our understanding of the PPCP fate in WWTPs, and be facilitated to develop a nanomaterial-based technology to achieve more efficient PPCP removal.

Unraveling Roles of Emerging Environmental Contaminants on Promoting the Spread of Antibiotic Resistance (Ji Lu)

Abstract: The dissemination of antibiotic resistance has become a major threat to public health. The spread of antibiotic resistance has been attributed to the overuse and misuse of antibiotics in clinic settings, agriculture and aquaculture. However, whether non-antibiotic, anti-microbial (NAAM) chemicals can directly induce antibiotic resistance is unclear. Thus, my PhD project focuses on exploring the potential roles of three ubiquitous types of NAAM chemicals, silver nanoparticles (Ag NP), triclosan (TCS) and triclocarban (TCC) in the dissemination of antibiotic resistance in the environment. To achieve the aim, one attempt is to investigate the antibiotic-like roles of Ag NPs, TCS and TCC on triggering antibiotic resistance through genetic mutation. The other direction is to evaluate the effects of Ag NPs, TCS and TCC on promoting the horizontal transfer of antibiotic resistance genes (ARGs) within and across species. In this seminar, the research on TCS will be presented showing that, at a concentration of 0.2 mg/L, triclosan (TCS) as a NAAM chemical induces multi-drug resistance (MDR) in wide-type Escherichia coli after 30 days exposure. The oxidative stress induced by TCS caused genetic mutations in fabI, frdD, marR, acrR and soxR, and subsequently up-regulated the transcriptions of genes encoding beta-lactamase and multi-drug efflux pump as well as down-regulates genes related to membrane permeability. Moreover, exposure to TCS concentration from 0.02 μg/L to 0.2 mg/L could enhance the ARG transfer within and across bacteria genera. These findings will enhance the understanding of potential roles of environmental NAAM chemicals in the global dissemination of antibiotic resistance in microbes.

Event Details
Date & Time: 
Friday, 19 January 2018
9am - 10am
Venue: AIBN Building 75, Level 1 Seminar Room

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