Odorous emissions of synthetic turf and its relationship with local communities.

Synthetic turf has been a mainstay of field sports and local communities for decades, and in that time, has faced both community and government pressure to ensure its safety and fitness for purpose. Considerable research and regulations have been applied to synthetic turf with regards to its safety, construction, potential toxicity, sports impact, as well as environmental considerations. However, very little attention has been paid to reports of odorous impacts from synthetic turf fields. This is problematic as odours are both a source of most complaints by communities towards other industries, as well as the fact that synthetic turf has a unique placement within communities themselves. It is wholly possible that the concerns surrounding synthetic turf are being modulated by the odours that the fields themselves produce through previously identified psychological mechanisms. As a result, ensuring good standards for synthetic turf with regards to odorous emissions should be benchmarked for community acceptability. This review investigates prior research into synthetic turf with regards to identified volatile organic compounds emitted, as well as proposing the means by which community stakeholders engage with synthetic turf, as well as how they should be consulted. From here, this review provides trajectories for future research within this space, and how regulatory bodies should address potential issues. This research space is currently in its infancy and therefore information relating to synthetic turf odour factors must be carefully considered.

Review of scientific research on air quality and environmental health risk and impact for PICTS.

Air quality (AQ) significantly impacts human health, influenced by both natural phenomena and human activities. In 2021, heightened awareness of AQ's health impacts prompted the revision of the World Health Organization (WHO) guidelines, advocating for stricter pollution standards. However, research on AQ has predominantly focused on high-income countries and densely populated cities, neglecting low- and middle-income countries, particularly Pacific Island Countries, Territories, and States (PICTS). This systematic review compiles existing peer-reviewed literature on AQ research in PICTS to assess the current state of knowledge and emphasize the need for further investigation. A systematic literature search yielded 40 papers from databases including Web of Science, Scopus, and Embase. Among the 26 PICTS, only 6 (Hawai'i, Fiji, Papua New Guinea, New Caledonia, Republic of Marshall Islands, and Pacific) have been subject to AQ-related research, with 4 considering the World Health Organization (WHO) parameters and 26 addressing non-WHO parameters. Analysis reveals AQ parameters often exceed 2021 WHO guidelines for PM2.5, PM10, SO2, and CO, raising concerns among regional governments. Studies primarily focused on urban, agricultural, rural, and open ocean areas, with 15 based on primary data and 14 on both primary and secondary sources. Research interests and funding sources dictated the methods used, with a predominant focus on environmental risks over social, economic, and technological impacts. Although some papers addressed health implications, further efforts are needed in this area. This review underscores the urgent need for ongoing AQ monitoring efforts in PICTS to generate spatially and temporally comparable data. By presenting the current state of AQ knowledge, this work lays the foundation for coordinated regional monitoring and informs national policy development.

Importance of 2,4,6-Trichloroanisole (TCA) as an odorant in the emissions from anaerobically stabilized dewatered biosolids.

Odours from stabilized biosolids after anaerobic digestion of wastewater sludge can cause local community impact. Apart from the well-known odorants such as sulfur compounds, contributions from other volatile organic compounds (VOCs) to nuisance odours is limited. The presence of compounds with low odour detection thresholds (ODTs) at low concentrations, can present challenges for analytical identification. Thirty-six biosolids samples were taken after anaerobic stabilisation and dewatering at a wastewater treatment plant, Sydney, Australia. Biosolid cake samples were stored outside in loosely covered trays under aerobic conditions, however without interactions with soil microorganisms as it would be in reality. All biosolids cake samples were analysed over a period of 35 days. Emissions were collected onto Tenax TA sorbent tubes using a U.S. EPA flux hood method at storage days 1, 3, 7, 10, 14, 21 and 35. Gas chromatography (GC) coupled with mass spectrometer detector (MSD) and an olfactory detection port (ODP) was used to identify a musty/moldy/earthy type odorant in the biosolids emissions as 2,4,6-trichloroanisole (TCA). Measured odour intensities, classified on a scale from 1 to 4, and odour characters were specified by three ODP assessors. TCA was identified in all biosolid cake emissions. The measured odour intensities of the TCA did not significantly alter as the biosolids were aged, however varied between biosolids cakes. Due to its odour intensity, 85% frequency of detection and its low ODT, which is orders of magnitudes lower than sulfur compounds, TCA should be considered as a potential odorant of concern in biosolids emissions.

Enhanced real-time cyanobacterial fluorescence monitoring through chlorophyll-a interference compensation corrections.

In situ fluorometers can be used as a real-time cyanobacteria detection tool to maintain safe drinking and recreational water standards. However, previous studies into fluorometers have established issues arising mainly from measurement inaccuracies due to green algae interference. Therefore, this study focusses on developing correction factors from a systematic study on the impact of green algae as an interference source. This study brings a novel technique where the chlorophyll-a (Chl-a) and phycocyanin measurements are used to correct the fluorometer output for interference bias; four fluorometers were tested against three key cyanobacterial species and the relationship between phycocyanin output, green algae and cyanobacteria concentrations were investigated. Good correlation (R2 > 0.9, p-value < 0.05) was found between the fluorometer phycocyanin output and increasing green algae concentration. The optimal correction method was selected for each of the fluorometer and cyanobacteria species pairs by validating against data from the investigation of green algae as an interference source. The correction factors determined in this study reduced the measurement error for almost all the fluorometers and species tested by 21%-99% depending on the species and fluorometer, compared to previous published correction factors in which the measurement error was reduced by approximately 11%-81%. Field validation of the correction factors showed reduction in fluorometer measurement error at sites in which cyanobacterial blooms were dominated by a single species.

A comparison of removal performance of volatile organic and sulfurous compounds between odour abatement systems.

Three types of odour abatement systems in sewer networks in Australia were studied for 18 months to determine the removals of different compounds. Six volatile sulfurous compounds and seven volatile organic compounds (VOCs) were further investigated. All types of odour abatement systems exhibited good removal of hydrogen sulfide with the biotrickling filters (BTFs) showing the highest consistent removal. Biofilters outperformed BTFs and activated carbon (AC) filters in the removal of dimethyl mono-, di- and tri-sulfide species at the low inlet concentrations typically found. AC filters exhibited little VOC removal with no compound consistently identified as having a removal greater than 0%. Biofilters outperformed BTFs in VOC removal, yet both had high removal variability.

Critical review of dog detection and the influences of physiology, training, and analytical methodologies.

Detection dogs serve a plethora of roles within modern society, and are relied upon to identify threats such as explosives and narcotics. Despite their importance, research and training regarding detection dogs has involved ambiguity. This is partially due to the fact that the assessment of effectiveness regarding detection dogs continues to be entrenched within a traditional, non-scientific understanding. Furthermore, the capabilities of detection dogs are also based on their olfactory physiology and training methodologies, both of which are hampered by knowledge gaps. Additionally, the future of detection dogs is strongly influenced by welfare and social implications. Most importantly however, is the emergence of progressively inexpensive and efficacious analytical methodologies including gas chromatography related techniques, "e-noses", and capillary electrophoresis. These analytical methodologies provide both an alternative and assistor for the detection dog industry, however the interrelationship between these two detection paradigms requires clarification. These factors, when considering their relative contributions, illustrate a need to address research gaps, formalise the detection dog industry and research process, as well as take into consideration analytical methodologies and their influence on the future status of detection dogs. This review offers an integrated assessment of the factors involved in order to determine the current and future status of detection dogs.

Emissions of volatile sulfur compounds (VSCs) throughout wastewater biosolids processing.

Volatile sulfur compounds (VSCs) are important contributors to nuisance odours from the processing of wastewater sludge and biosolids. However, emission characteristics are difficult to predict as they vary between sites and are likely to be affected by biosolids processing configuration and operation. VSC emissions from biosolids throughout 6 wastewater treatment plants (WWTPs) in Sydney, Australia were examined in this study. H2S was the VSC found at the highest concentrations throughout the WWTPs, with concentrations ranging from 7 to 39,000µg/m3. Based on odour activity values (OAVs), H2S was typically also the most dominant odorant. However, methyl mercaptan (MeSH) was also found to be sensorially important in the biosolids storage areas given its low odour detection threshold (ODT). High concentrations of VOSCs such as MeSH in the storage areas were shown to potentially interfere with H2S measurements using the Jerome 631-X H2S sensor and these interferences should be investigated in more detail. The VSC composition of emissions varied throughout biosolids processing as well as between the different WWTPs. The primary sludge and biosolids after dewatering and during storage, were key stages producing nuisance odours as judged by the determination of OAVs. Cluster analysis was used to group sampling locations according to VSC emissions. These groups were typically the dewatered and stored biosolids, primary and thickened primary sludge, and waste activated sludge (WAS), thickened WAS, digested sludge and centrate. Effects of biosolids composition and process operation on VSC emissions were evaluated using best subset regression. Emissions from the primary sludge were dominated by H2S and appeared to be affected by the presence of organic matter, pH and Fe content. While volatile organic sulfur compounds (VOSCs) emitted from the produced biosolids were shown to be correlated with upstream factors such as Fe and Al salt dosing, anaerobic digestion and dewatering parameters.

Survey of the effect of odour impact on communities.

In the context of environmental malodour, surveys are valuable as they allow for the relatively detailed analysis of multiple factors pertaining to odour perception and subsequent reaction. However, the causes for an individual to experience odour impact while a neighbour will not are still not understood. The goal of this current survey design was to consolidate varying research paths for surveys within the environmental odour research space. This survey investigated the area of effect for wastewater treatment plants by using stratified random sampling techniques that radiated from the industrial areas. Additionally, this survey provided a "non-alerted" response to environmental malodour that represents a step forward for ecological validity. We found a small number of items relating to odour annoyance and home ownership that can be used in order to predict odour impact for individual community members. However, we also did not find any relationship with odour impact and perceived control. This survey design and analysis reconciles the varied approaches towards community surveys administered in prior literature, as well as providing information to improve future community engagement policies.

Unrepresented community odour impact: Improving engagement strategies.

Complaints for odour causing industry continue to increase in numeracy and severity. One assessment approach using Gas Chromatography-Mass Spectrometry/Olfactometry (GC-MS/O), has been used primarily to identify priority odourants within a standardised panel. We investigated the variation of response between participants of average and high olfactory sensitivity, and discovered that current GC-MS/O methodologies do not represent the entirety of community odour impact. Based on these results we constructed a Biosolids Processing Odour Wheel followed by a Community Odour Wheel for use by untrained community members and site operators. By using the information gathered from this research, as well as odour testing workshops for a wastewater treatment plant's staff and community surrounding the facility, we established a communicative system, which was subsequently incorporated into an online dynamic odour observation platform. This platform provides the WWTP with meaningful information from the community, as well as a common language for which to discuss environmental malodour with all stakeholders.

Distribution and sensorial relevance of volatile organic compounds emitted throughout wastewater biosolids processing.

A diverse range of volatile organic compounds (VOCs) are emitted from wastewater biosolids processing. Odorous emissions are predominately made up of volatile sulfur compounds (VSCs) which are typically the only odorants measured. However, a range of VOCs are known to contribute to malodours yet previous studies often overlook the contribution of VOCs in comparison with VSCs. This study aims to evaluate how emissions are affected by different biosolids processing configurations, and if any non-sulfur VOCs should be included in odour measurement and management. Non-sulfur VOCs emitted from biosolids throughout six wastewater treatment plants in the Sydney, Australia region were measured at six locations on average twice each week over 2-3weeks at each site. Variations in types of VOCs emitted throughout and between the sites were assigned to differences in WWTP processing configurations, plant operation and variations in industrial and municipal flows to the sewer network, referred to as sewer catchments. The presence of VOCs is likely due to biotic generation as well as industrial or residential additions to the sewer network. The dewatered and stored biosolids samples had the highest levels of VOC emissions. Sensorially important odorants were p-cresol and butanoic acid, based on the frequency of detection and odour activity values. Other compounds with a high risk of nuisance impacts were trimethylamine, indole and phenol emitted from the dewatered and stored biosolids, and volatile fatty acids from the anaerobic digester inlet and outlet at one particular site. The findings show that non-sulfur VOCs should be added to odorant monitoring campaigns at WWTPs. Identification of VOCs as sensorially important odorants opens opportunities for the more efficient management of nuisance odours, through targeted odour control or process improvement.

Sulfur flows and biosolids processing: Using Material Flux Analysis (MFA) principles at wastewater treatment plants.

High flows of sulfur through wastewater treatment plants (WWTPs) may cause noxious gaseous emissions, corrosion of infrastructure, inhibit wastewater microbial communities, or contribute to acid rain if the biosolids or biogas is combusted. Yet, sulfur is an important agricultural nutrient and the direct application of biosolids to soils enables its beneficial re-use. Flows of sulfur throughout the biosolids processing of six WWTPs were investigated to identify how they were affected by biosolids processing configurations. The process of tracking sulfur flows through the sites also identified limitations in data availability and quality, highlighting future requirements for tracking substance flows. One site was investigated in more detail showing sulfur speciation throughout the plant and tracking sulfur flows in odour control systems in order to quantify outflows to air, land and ocean sinks. While the majority of sulfur from WWTPs is removed as sulfate in the secondary effluent, the sulfur content of biosolids is valuable as it can be directly returned to soils to combat the potential sulfur deficiencies. Biosolids processing configurations, which focus on maximising solids recovery, through high efficiency separation techniques in primary sedimentation tanks, thickeners and dewatering centrifuges retain more sulfur in the biosolids. However, variations in sulfur loads and concentrations entering the WWTPs affect sulfur recovery in the biosolids, suggesting industrial emitters, and chemical dosing of iron salts are responsible for differences in recovery between sites.

Odorous volatile organic compound (VOC) emissions from ageing anaerobically stabilised biosolids.

Opportunities for the beneficial re-use of biosolids are limited by nuisance odour emissions. Volatile organic compounds (VOCs) from anaerobically stabilised biosolids were measured to identify compounds that could contribute to the overall odour character of nuisance emissions. Flux hood sampling and chemical analysis were used to identify VOCs emitted from biosolids as they were stored in ambient conditions. Compounds emitted varied as the biosolid cakes were stored for a period of 50 days. VOCs detected in the biosolids are likely to occur from catchment sources as well as abiotic and biotic generation in the wastewater processing and the biosolids as they are stored. Odour activity values (OAVs) were used to compare odorants. Trimethylamine was the only VOC detected that exceeded the sulfur compounds in terms of OAVs. Other compounds such as limonene, ethyl methyl benzene and acetic acid were detected at concentrations exceeding their olfactory detection limits, however at lower OAVs than sulfur compounds.

The impact of malodour on communities: a review of assessment techniques.

Malodours remain the biggest source of complaints regarding environmental issues. This factor is likely to increase, as the urban development steadily encroaches into areas that have malodourous emitting industries (such as wastewater and waste management operations and intensive livestock practices), and has the potential to be both time and fiscally expensive. Despite the enormous amount of research involved in odour detection and abatement, as well as the creation of several distinct methodologies, there has yet been no definitive procedure to evaluate odour impact on communities, as well as community response. This paper is a review of the current methods that explore this problem, as well as a précis of this research field's goals and challenges. The first aim of this review is to illustrate the dichotomy between regulatory-established procedures, such as panellist testing, and methods that are centred around producing a more comprehensive explanation of factors that influence an odour's impact on a community or individual. In that regard, we have addressed several predominant paradigms of inquiry for this field: analytical methods, panellist testing, qualitative research, and survey methods, with associated variants. Secondly, the challenges of measuring and monitoring community impact are discussed. While the quantification of odorants is crucial to appreciating impact, individual-based modifiers of perception have an enormous scope for which to shape the effect of those odours. Perceptual differences are also likely the most dominant variables that influence the elicited behaviour of individuals who have experienced malodour exposure.

Hydrophobically-associating cationic polymers as micro-bubble surface modifiers in dissolved air flotation for cyanobacteria cell separation.

Dissolved air flotation (DAF), an effective treatment method for clarifying algae/cyanobacteria-laden water, is highly dependent on coagulation-flocculation. Treatment of algae can be problematic due to unpredictable coagulant demand during blooms. To eliminate the need for coagulation-flocculation, the use of commercial polymers or surfactants to alter bubble charge in DAF has shown potential, termed the PosiDAF process. When using surfactants, poor removal was obtained but good bubble adherence was observed. Conversely, when using polymers, effective cell removal was obtained, attributed to polymer bridging, but polymers did not adhere well to the bubble surface, resulting in a cationic clarified effluent that was indicative of high polymer concentrations. In order to combine the attributes of both polymers (bridging ability) and surfactants (hydrophobicity), in this study, a commercially-available cationic polymer, poly(dimethylaminoethyl methacrylate) (polyDMAEMA), was functionalised with hydrophobic pendant groups of various carbon chain lengths to improve adherence of polymer to a bubble surface. Its performance in PosiDAF was contrasted against commercially-available poly(diallyl dimethyl ammonium chloride) (polyDADMAC). All synthesised polymers used for bubble surface modification were found to produce positively charged bubbles. When applying these cationic micro-bubbles in PosiDAF, in the absence of coagulation-flocculation, cell removals in excess of 90% were obtained, reaching a maximum of 99% cell removal and thus demonstrating process viability. Of the synthesised polymers, the polymer containing the largest hydrophobic functionality resulted in highly anionic treated effluent, suggesting stronger adherence of polymers to bubble surfaces and reduced residual polymer concentrations.

Examination of the physical properties of Microcystis aeruginosa flocs produced on coagulation with metal salts.

Coagulation-flocculation (C-F) is a key barrier to cyanobacterial and algal cell infiltration in water treatment plants during seasonal blooms. However, the resultant cell floc properties, in terms of size, strength and density, which dominate under different coagulation conditions and govern cell removal, are not well understood. This paper investigated the floc properties produced during C-F of the cyanobacterium, Microcystis aeruginosa, under low and high doses of aluminium sulphate and ferric chloride coagulants and at different pH values, so as to promote charge neutralisation (CN) and sweep flocculation (SF) dominant conditions (or a combination of these). It was demonstrated that application of ferric chloride produced larger flocs that resulted in higher cell removal during jar testing. These flocs were also larger than those observed for natural organic matter (NOM) and kaolin, suggesting a role of algogenic organic matter (AOM) as an inherent bioflocculant. Under SF conditions, stronger flocs were produced; however, these had lower capacity for size recovery after exposure to high shear. Analysis of particle size distribution demonstrated that large scale fragmentation followed by erosion dominated for CN while erosion dominated under SF conditions. Overall, marked differences were observed dependent on the coagulation regime imposed that have implications for improving robustness of cell removal by downstream separation processes. While the cyanobacterium, M. aeruginosa, appeared to share general floc characteristics commonly observed for NOM and kaolin flocs, there were distinct differences in terms of size and strength, which may be attributed to AOM.

Reduced sulfur compounds in the atmosphere of sewer networks in Australia: geographic (and seasonal) variations.

The management of odorous emissions from sewer networks has become an important issue for sewer system operators resulting in the need to better understand the composition of reduced sulfur compounds (RSCs). Gaseous RSCs including hydrogen sulfide (H2S), methanethiol (MeSH), dimethyl sulfide (DMS), carbon disulfide (CS2), dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS) were measured in the atmosphere of selected sewer networks in two major Australian cities (Sydney and Melbourne) during 2011-2012. The RSC concentrations in the sewer air were detected in a highly variable range. H2S and MeSH were found at the highest concentrations, followed by DMS (39.2-94.0 µg/m(3)), CS2 (18.3-19.6 µg/m(3)), DMDS (7.8-49.6 µg/m(3)) and DMTS (10.4-35.3 µg/m(3)). Temporal trends in the occurrence of targeted RSCs were observed and the highest sulfur concentration occurred either in summer or spring, which are typically regarded as the warmer seasons. Statistical significant difference in the magnitude of targeted RSCs was found between samples collected in Sydney and Melbourne.

Is H2S a suitable process indicator for odour abatement performance of sewer odours?

Odour abatement units are typically designed and maintained on H(2)S concentrations, but operational failures are reported in terms of overall odour removal, suggesting a wide range of malodorous compounds emitted from sewers that may not be efficiently removed by existing odour abatement processes. Towards providing greater insight into this issue, several activated carbon filters and biofilters treating odorous emissions from sewer systems in Sydney (Australia) were monitored by collecting and analysing gas samples before and after treatment. The monitoring studies were conducted by both olfactometric measurements and gas-chromatography-based chemical analysis. Single H(2)S assessment often failed to indicate the odour abatement performance for treatment systems in the abatement units studied, particularly when the incoming H(2)S concentrations were in the sub-ppm range (i.e. below H(2)S odour threshold). Chemical analysis indicated that some non-H(2)S odorous compounds were not removed efficiently during odour treatment. Additionally, when odour eliminations were correlated with the removal of individual compounds (Pearson's correlations) it was observed that the correlation (with a coefficient of 0.79) was best when the overall removal of all the measured odorous compounds that exceeded their odour threshold values was used for the analysis. These findings may help to further advance the design and operation of odour abatement processes to address the treatment of sewer odour emissions.

Stability of volatile sulfur compounds (VSCs) in sampling bags - impact of temperature.

Volatile sulfur compounds (VSCs) are a major component of odorous emissions that can cause annoyance to local populations surrounding wastewater, waste management and agricultural practices. Odour collection and storage using sample bags can result in VSC losses due to sorption and leakage. Stability within 72 hour storage of VSC samples in three sampling bag materials (Tedlar, Mylar, Nalophan) was studied at three temperatures: 5, 20, and 30 °C. The VSC samples consisted of hydrogen sulfide (H2S), methanethiol (MeSH), ethanethiol (EtSH), dimethyl sulfide (DMS), tert-butanethiol (t-BuSH), ethylmethyl sulfide (EMS), 1-butanethiol (1-BuSH), dimethyl disulfide (DMDS), diethyl disulfide (DEDS), and dimethyl trisulfide (DMTS). The results for H2S showed that higher loss trend was clearly observed (46-50% at 24 hours) at 30 °C compared to the loss at 5 °C or 20 °C (of up to 27% at 24 hours) in all three bag materials. The same phenomenon was obtained for other thiols with the relative recoveries after a 24 hour period of 76-78% at 30 °C and 80-93% at 5 and 20 °C for MeSH; 77-80% at 30 °C and 79-95% at 5 and 20 °C for EtSH; 87-89% at 30 °C and 82-98% at 5 and 20 °C for t-BuSH; 61-73% at 30 °C and 76-98% at 5 and 20 °C for 1-BuSH. Results for other sulfides and disulfides (DMS, EMS, DMDS, DEDS) indicated stable relative recoveries with little dependency on temperature (83-103% after 24 hours). DMTS had clear loss trends (with relative recoveries of 74-87% in the three bag types after 24 hours) but showed minor differences in relative recoveries at 5, 20, and 30 °C.

Investigation of PM10 sources in Santa Catarina, Brazil through graphical interpretation analysis combined with receptor modelling.

Epidemiological studies have documented that elevated airborne particulate matter (PM) concentrations, especially those with an aerodynamic diameter less than 10 microm (PM10), are associated with adverse health effects. Two receptor models, UNMIX and positive matrix factorization (PMF), were used to identify and quantify the sources of PM10 concentrations in Tubarão and Capivari de Baixo, Santa Catarina, Brazil. This region is known for its high pollution levels due to intense industrial activity and exploitation of natural resources. PM10 samples were collected using high volume samplers at two sites in the region and statistical exploratory analysis techniques were applied to identify and assess PM10 sources. The two primary PM10 sources were identified as soil re-suspension/road dust emissions and coal burning emissions, contributing 65-75% and 15-25% of the PM10, respectively. The study confirmed the significance of the influence of local PM10 emissions (power plants, soil re-suspension and road dust emissions) on regional air quality, although no violations of the Brazilian PM10 standards (limit of 150 microg/m3) were observed, with a mean concentration of 27.6 microg/m3 measured in this study. This study demonstrated the usefulness of statistical exploratory analysis techniques in assessing the validity of modelling results and contributing to the interpretation of ambient air quality data.

Removal of trace organic chemical contaminants by a membrane bioreactor.

Emerging wastewater treatment processes such as membrane bioreactors (MBRs) have attracted a significant amount of interest internationally due to their ability to produce high quality effluent suitable for water recycling. It is therefore important that their efficiency in removing hazardous trace organic contaminants be assessed. Accordingly, this study investigated the removal of trace organic chemical contaminants through a full-scale, package MBR in New South Wales, Australia. This study was unique in the context of MBR research because it characterised the removal of 48 trace organic chemical contaminants, which included steroidal hormones, xenoestrogens, pesticides, caffeine, pharmaceuticals and personal care products (PPCPs). Results showed that the removal of most trace organic chemical contaminants through the MBR was high (above 90%). However, amitriptyline, carbamazepine, diazepam, diclofenac, fluoxetine, gemfibrozil, omeprazole, sulphamethoxazole and trimethoprim were only partially removed through the MBR with the removal efficiencies of 24-68%. These are potential indicators for assessing MBR performance as these chemicals are usually sensitive to changes in the treatment systems. The trace organic chemical contaminants detected in the MBR permeate were 1 to 6 orders of magnitude lower than guideline values reported in the Australian Guidelines for Water Recycling. The outcomes of this study enhanced our understanding of the levels and removal of trace organic contaminants by MBRs.