Healthcare-associated infections (HAIs) from waterborne and wastewater-associated pathogens are an increasing public health threat due to rising antimicrobial resistance. Within plumbing systems, microbial water quality and biofilm formation is influenced by interconnected physical, chemical and biological factors. As an integrated water-wastewater system, healthcare handbasins can become contaminated with pathogens from incoming water, wastewater plumbing, or during handwashing. Contaminated fixtures are an infection risk, particularly for immunocompromised individuals, with exposure occurring through ingestion, inhalation, aspiration and direct or indirect skin contact with water or aerosols. Handbasin design influences biofilm formation and bacterial transmission via splashing and aerosol generation, impacting infection risks. This review examines international healthcare handbasin design guidelines against scientific evidence to identify areas of alignment and divergence.Across the thirty-nine countries reviewed, infection control design guidelines varied considerably. Eight countries considered basin shape to improve drainage and minimise splashing. Offset drain positioning was a key design consideration for infection control, which was identified to reduce splashing and pathogen dispersal across the literature. Aerosolization and biofilm-related design risks were often addressed, however, inconsistent recommendations on outlet fittings, outlet flow rates and faucet operation reflected competing priorities between infection control, user safety, and water efficiency.This inconsistent consideration of design for infection control highlights a disconnect between policy and evidence. Further research is needed to understand how design features and operational conditions influence infection risk. Future designs must balance biofilm control, splashing and aerosol reduction, support for clinical handwashing techniques, water efficiency and scald prevention to protect patients and reduce HAIs.

ISSUE ADDRESSED:The integration of a new standard for food safety in Australia signifies a notable step toward national unity in the adoption of Hazard Analysis and Critical Control Point (HACCP) principles and contemporary food safety management tools for the food service and retail sector. The standard introduces key measures, including certification of food safety supervisors, food safety training requirements for food handlers, and means for substantiating control of food safety hazards throughout key food handling processes. METHODS:This study explored the experiences and perspectives of local regulators regarding the implementation and feasibility of the new standard. Data were collected via an online survey and semi-structured interviews with Environmental Health Practitioners across two Australian states. RESULTS:Findings reveal that implementation of the standard varied between states, largely shaped by the degree of support provided by respective state authorities. Six key barriers to effective implementation emerged from participant accounts. CONCLUSIONS:In response, five targeted recommendations are proposed, grounded in established health promotion principles. Until these challenges are adequately addressed, the standard risks remaining ineffectual, limiting its capacity to enhance public health outcomes. SO WHAT?: The key to effective implementation and realisation of Standard 3.2.2A as healthy public policy lies within the central tenets of public health theory and practice.

Abstract Flow restrictors are widely used to improve water efficiency by limiting flow rates in faucets and showerheads. While these devices contribute to significant reductions in water consumption and associated energy costs, they may also pose unintended risks to microbial water quality. In healthcare and other high‐risk settings, reduced flow rates can promote water stagnation, biofilm formation and the proliferation of opportunistic waterborne pathogens, increasing infection risks for immunocompromised individuals. Regulatory frameworks governing water conservation and microbial water quality vary across jurisdictions, often addressing these concerns separately rather than in an integrated manner. This commentary examines the dual role of flow restrictors in sustainable water management and public health, highlighting the need for regulatory alignment and risk informed water efficiency strategies. A balanced approach is essential to ensure that water conservation efforts do not inadvertently compromise microbial safety in building water systems.

Building water systems are internationally recognised reservoirs for opportunistic premise plumbing pathogens, including Legionella, the causative agent of Legionnaires’ disease. Inadequate design, operation and maintenance can promote Legionella proliferation and expose building occupants to potentially fatal infection. Effective management is therefore critical; however, there is limited international evidence regarding how guidelines for controlling Legionella risk are implemented in practice. Despite extensive Australian guidance, little is known about the practical management of Legionella risk in building water systems. This study explored current practices among hydraulic engineers, facility managers, plumbers, and water retreatment consultants. An online survey with follow-up interviews was conducted and the responses were then compared with existing guidelines and historical case studies published in the literature. Key findings indicated that current practice is predominantly risk-focused, with monitoring, system disinfection, routine maintenance, and targeted engineering modifications forming the core control measures. Case studies demonstrated substantial variability in how practitioners select and apply interventions, reflecting the complexity and diversity of building water systems. Insufficient maintenance and poor system design emerged as the leading contributors to Legionella proliferation, while control measures failed primarily due to incorrect or inappropriate selection. Budget constraints and lack of knowledge were identified as the major barriers to implementing effective and sustained control strategies. These findings are of international relevance, highlighting the need for control measures underpinned by risk assessment and comprehensive system monitoring and providing an evidence base to strengthen guidelines for effective Legionella management in building water systems globally.

Environmental sampling of fungal spores is critical for assessing exposure risks, but current methods often miss low-abundance or spatially dispersed spores, highlighting the need for more sensitive sampling methods. This study explores the use of plasma polymerization to chemically modify air filters for enhanced fungal spore capture. Polyethylene terephthalate (PET) filters are coated with nanothin films from four monomers -acrylic acid, 2-methyl-2-oxazoline (POX), 1,7-octadiene, and perfluorooctane (PFO)- and characterized using ellipsometry, X-ray photoelectron spectroscopy, and contact angle measurements to evaluate film thickness, chemistry, and wettability. A custom aerosolization chamber was used to test the capture efficiency of plasma-modified filters for airborne spores from four species: Aspergillus niger, Cladosporium sp., Penicillium roqueforti, and Rhodotorula glutinis. Quantitative analysis using hemocytometry and dry biomass measurement reveals species-specific adhesion patterns that are predominantly driven by surface chemistry. Hydrophobic PFO-coated filters achieved the highest capture of filamentous fungi, while hydrophilic POX coatings best captured the tested yeast. Coating thickness had no significant effect, highlighting the primacy of surface chemistry over film depth. These findings establish plasma polymerization as an effective strategy to tailor filter surfaces for selective fungal spore capture, providing a proof-of-concept for functionalized air filters that support improved bioaerosol monitoring in built environments.

As pressure on urban water resources grows, roof-harvested rainwater is increasingly used for drinking and domestic purposes. However, changing roof infrastructure and expanding vulnerable populations may be introducing under-recognised public health risks. This study assessed the microbiological and physicochemical quality of domestic roof-harvested rainwater across Adelaide and the Adelaide Hills, South Australia. One hundred rainwater tanks were sampled, and 97 households completed a survey on rainwater use, system characteristics, wildlife presence and rooftop solar infrastructure. Most households used rainwater for drinking (67%) and gardening (76%), and 62% had rooftop solar panels. Quantitative PCR detected enteric and opportunistic pathogens in a proportion of tanks, including Campylobacter jejuni (13%), Pseudomonas aeruginosa (12%), Salmonella spp. (10%) and Shigella spp. (3%), with pathogens also present in tanks used for drinking. Between 1 and 4% of tanks exceeded Australian Drinking Water Guideline health values for cadmium, iron, manganese, lead and arsenic, while 1-11% exceeded aesthetic values for zinc, manganese, aluminium and sodium. In unadjusted analyses, elevated metal concentrations were associated with solar panel presence (p = 0.004) and tank type (p = 0.004). However, multivariable analysis adjusting for tank material showed that households with solar panels had lower odds of elevated metal concentrations (aOR = 0.265, p = 0.026), while metal tank construction was associated with increased odds of elevated metal concentrations (p = 0.031). These findings indicate that domestic rainwater systems can act as reservoirs of microbial and chemical hazards with potential implications for human health. As climate change and water insecurity increase reliance on alternative water sources, understanding and managing these risks will become increasingly important. Further research is needed to examine how evolving roof infrastructure affects contamination pathways and emerging risks, including antimicrobial resistance, within domestic rainwater systems.

Sequencing-batch operation of high-rate algal ponds selectively enriches photogranules or filamentous algae, improving solids separation and producing clearer effluent suitable for safe reuse.

Bilgewater is a mixture of oil, water, suspended solids, and other contaminants that collects in the lower inside areas of marine vessels and its discharge into the marine environment contributes to ocean pollution. Due to its complex composition and ecological impacts, effective management is critical. This systematic review examined existing research on bilgewater composition and assesses available treatment technologies to identify knowledge gaps and options for treatment. The Scopus database was searched for studies published between 1980 and 2025 that examined bilgewater treatment or its chemical and microbiological characteristics. Studies lacking independent validation or functioning as commercial promotion were excluded to minimise bias. A total of seventy-seven studies were examined. These revealed significant heterogeneity in bilgewater’s chemical and microbiological profiles across vessels, sampling locations, and environmental conditions. Microbiological analysis identified the presence of hydrocarbon-degrading bacteria, corrosion-associated species, and potentially pathogenic species. Bilgewater treatment approaches included biological, electrochemical, filtration, coagulation, and multi-barrier systems, each with distinct advantages and limitations. The variability of bilgewater composition highlights the need for standardised assessment methods and guidance on which treatment systems are most effective in different situations. Future research is also needed to understand the interplay between the chemical and microbial characteristics of bilgewater and to investigate the removal of trace metals, non-indigenous species, pathogenic bacteria, and emulsified oil. Addressing these challenges is imperative to developing robust regulations and innovative control solutions.

Public health regulation in Australia operates through complex regulatory frameworks which includes Acts, Regulations, Codes of Practice, Guidelines and policy directives. While the public health significance of Legionella control is well recognised, limited research has examined how regulatory instruments collectively constitute the framework for Legionella management or alignment with international guidance. ISO 31000:2018 Risk Management – Guidelines-provide a structured approach to risk identification, assessment and treatment, emphasising context specific application and continual improvement. This aligns closely with the World Health Organization (WHO) Water Safety Plan approach, adopted across Australian jurisdictions to manage water related hazards. National standards, including AS/NZS 3666, complement this guidance by specifying technical requirements for the prevention and control of Legionella in building water systems. This review examines regulatory frameworks for Legionella management across Australia with New Zealand included as a comparator. A comprehensive search of the AustLII database was conducted to identify the regulatory components relevant to Legionella management across Australian states and territories. Additional policy documents were identified from previous literature reviews and targeted searches of state and territory health department websites. Comparable regulatory and guidance documents from New Zealand were included for analysis. Ninety-one documents, including eleven Acts and regulations, were reviewed and assessed for consistency with WHO guidance on Legionella prevention and control. Substantial variation was observed across jurisdictions in regulatory scope, system registration requirements, and the structure and frequency of risk assessments. Differences were also identified in microbiological monitoring requirements, sampling frequencies, threshold limits, regulatory responses to elevated heterotrophic colony counts and Legionella detections, and prescribed decontamination protocols. Management of high-risk system components, including thermostatic mixing valves, dead legs, and aerosol-generating devices varied. Notwithstanding these differences, jurisdictions consistently recognised Legionella as a significant public health hazard, referenced AS/NZS 3666, and emphasised risk-based management and routine monitoring. Comparative analysis of regulatory frameworks demonstrates significant disparities in public health legislation and policy related to Legionella prevention. These findings demonstrate the need for evidence informed policy and national coherence to strengthen Legionella control and better protect public health.

Toilet flushing is a daily activity that can generate bioaerosols in indoor spaces. This exposure pathway is increasingly important in the context of emerging pathogens, changing water systems, and high indoor occupancy. Stronger empirical evidence is needed to support risk-based decision-making to protect human health. This systematic literature review examined factors influencing aerosol and bioaerosol concentrations generated through toilet flushing, with a focus on toilet design, target microorganisms, and air sampling methods relevant to exposure and risk assessment. Twenty-two studies met the inclusion criteria. Across studies, higher seeding concentrations and larger flush volumes were generally associated with higher aerosol and bioaerosol concentrations, indicating that source loading and flushing energy are the primary drivers of exposure-relevant aerosol generation. In contrast, evidence for independent effects of flushing pressure, lid position, and ventilation was limited and inconsistent. Probability density functions of log₁₀-transformed aerosol and bioaerosol concentrations were developed for seeded and unseeded conditions to strengthen quantitative microbial risk assessment (QMRA) inputs where direct air sampling is not feasible. Overall, the findings highlight the central role of toilet design and source microbial loading in shaping bioaerosol exposure, with important implications for risk assessment, building design, and infection control in an era of water security pressures and emerging infectious diseases.

This review investigates the role of wild birds as reservoirs and vectors of antimicrobial-resistant bacteria and antimicrobial resistance genes, and the implications for human health via contamination of harvested rainwater. A systematic literature review revealed that urban-adapted birds, especially gulls and pigeons, frequently carry clinically relevant antimicrobial-resistant bacteria including Carbapenem resistant Enterobacterales (CRE), multidrug-resistant Escherichia coli, extended-spectrum beta-lactamases (ESBL)-producing E. coli, and methicillin-resistant Staphylococcus aureus (MRSA) as well as colistin and macrolide-lincosamide-streptogramin (MLS) resistance genes. Due to urbanisation, these birds often forage in contaminated urban environments such as landfills, sewage sites and waste deposits, which increases their exposure to antimicrobial-resistant bacteria and antimicrobial resistance genes raising concerns about their increasing role in the environmental dissemination of AMR. Roof-harvested rainwater, a growing alternative water source amid climate change and water scarcity, can be contaminated by bird droppings containing antimicrobial-resistant bacteria and antimicrobial resistance genes. Despite its widespread use, harvested rainwater remains largely unregulated, presenting a public health risk. The findings from this review highlights the need for increased monitoring, targeted research, and improved risk management strategies to address AMR transmission from birds to humans via environmental pathways such as harvested rainwater.

The management of wastewater from recreational vehicles (hereafter RV), particularly in regional areas, presents challenges for wastewater treatment facilities due to the use of disinfecting, deodorising and sanitising (hereafter DDS) products in onboard toilets. This study aimed to determine the impact on wastewater quality due to use of DDS products by RV users. An online survey of Australian RV users (n = 160) was conducted to evaluate user knowledge and usage patterns of DDS. The results from the study showed that 65% of the respondents routinely used DDS products, and 83% of these users adhered to the recommended dosages. The predominant product used contained bronopol as the active biocide ingredient. Bronopol is a broad-spectrum biocide that degrades into formaldehyde. This study found that RV users added biocide in levels that may create challenges for wastewater treatment, particularly in regional communities.

High-rate algal ponds (HRAPs) have been shown to be an effective, reliable and cost-efficient wastewater treatment technology; however, their wider adoption requires improvement in effluent quality without compromising their simplicity...

Worldwide, Phytophthora cinnamomi is one of the most devastating plant pathogens. It infects almost 5000 plant species, causing death and habitat loss. There is a need for improved monitoring and management strategies to prevent the spread of this plant pathogen. The methods used for detection and identification have been established, but there are many variations depending on the species of Phytophthora, resources available, limitations of time and laboratory protocols, including previous knowledge or specialists involved. This review examined papers published from 2011 to 2025 that describe methods used to detect P. cinnamomi from environmental samples. Sixty-one papers were identified and included in this review. Collectively these papers showed that sampling approaches can include either direct sampling of soil, roots, plant tissue, and water, and indirect sampling by environmental baiting. Detection methods then can contain up to three main processes, including baiting, culture-based detection and isolation, and molecular confirmation. The sampling and detection methods identified in this review were used to develop a decision making flowchart that will help future researchers and management to choose the most appropriate methodological approach to identify P. cinnamomi from the environment. The flow chart presents methods based on laboratory time; resources available; and the type of sample collected. This information will increase the reliability of detection and improve the allocation of resources. This ultimately will improve the monitoring of P. cinnamomi to determine the spread of the pathogen, and to evaluate different management and control strategies to minimise its spread and impact on native vegetation, agriculture, forestry and horticulture.

The caravan and recreational vehicle (RV) industry is rapidly expanding in Australia, with increasing use of self-contained vehicles fitted with blackwater tanks. In rural regions without sewerage infrastructure, wastewater is emptied into dumpsite holding tanks and trucked to community treatment plants. However, little is known about the quality of this wastewater. This study is the first to characterise RV dumpsite wastewater in Australia, with samples collected across three rural South Australian sites over three seasons. Compared with traditional wastewater treatment plant inlets, RV wastewater was markedly stronger: suspended solids averaged 450 mg L-1 versus 105 mg L-1, ammonium 1321 mg L-1 versus 83.1 mg L-1, nitrate 8.2 mg L-1 versus 0.2 mg L-1, phosphate 108.7 mg L-1 versus 13.1 mg L-1, and BOD5 2597 mg L-1 versus 210 mg L-1. E. coli abundance was similar across sites. These elevated concentrations highlight risks of hydraulic and biological stress for rural treatment systems.

IntroductionFree-living amoebae (FLA) are commonly found in drinking water systems and biofilms, posing public health risks both as pathogens and as hosts for opportunistic bacteria such as Legionella spp. and Mycobacterium spp. Current water management practices are often insufficient to control biofilm-associated FLA and their intracellular pathogens.MethodsThis study evaluated the efficacy of multiple disinfectants—thermal disinfection (70 °C), hydrogen peroxide, 2-methyl-4-isothiazolin-3-one, benzalkonium chloride (BAC), sodium hypochlorite, and chlorine dioxide—against planktonic trophozoites and cysts of five FLA strains: Acanthamoeba DB1, Allovahlkampfia DS1, Stenamoeba DS1, Vermamoeba vermiformis HB7, and Acanthamoeba polyphaga ATCC® 30461™. Disinfectants were tested at varying concentrations and exposure times.ResultsThermal disinfection was the most effective treatment, followed by hydrogen peroxide. Exposure to 70 °C for 45 min achieved >4 log10 reduction of all FLA trophozoites. Thermal treatment at 70 °C for 60 min produced >4 log10 reduction for all cysts except V. vermiformis HB7, which showed greater thermal tolerance.DiscussionThe findings demonstrate that thermal disinfection is a highly effective strategy for inactivating multiple FLA species in their trophozoite and cyst forms. Further research is needed to evaluate the feasibility and effectiveness of applying these strategies to control biofilm-associated FLA within plumbing fixtures and drinking water distribution systems.

BACKGROUND:Antimicrobial-resistant (AMR) pathogens in drinking water plumbing systems represent a significant yet underestimated public health threat. METHODS:This is the first study to use qPCR and culture-based methods to investigate the prevalence of key AMR threats, meticillin resistant Staphylococcus aureus (MRSA) and carbapenem resistant Pseudomonas aeruginosa and Acinetobacter baumannii, in Australian hospital and residential drinking water and biofilm samples. FINDINGS:Seventy-three per cent of residential water and biofilm samples were qPCR positive for at least one target pathogen compared with 38% of hospital samples, and 45% of residential plumbing fixtures harboured at least two target pathogens. Thirty-seven per cent of water and biofilm samples were qPCR positive for P. aeruginosa, 22.3% for A. baumannii and 21.7% for S. aureus. Using culture, 10% of samples were positive for P. aeruginosa, 8% for A. baumannii and 7% for S. aureus. Of these, 29% of P. aeruginosa and 28% of A. baumannii culture isolates were carbapenem resistant, and 54% of S. aureus isolates were identified as MRSA. Drain biofilms were the most common reservoir for AMR A. baumannii, S. aureus and P. aeruginosa. Carbapenem resistance genes including blaNDM-1, blaOXA-48, blaKPC-2 and blaVIM were found in biofilm samples otherwise negative for P. aeruginosa, indicating plumbing biofilms may act as eDNA reservoirs. CONCLUSIONS:These findings underscore the critical role of plumbing biofilms as hotspots for diverse AMR pathogens, amplifying risks for vulnerable populations, particularly in home healthcare settings. This study highlights an urgent need for enhanced surveillance and targeted interventions to mitigate AMR risks in drinking water plumbing systems.

PurposeFood safety inspection is a key health protection measure applied by Environmental Health Practitioners (EHPs) to reduce the risk of foodborne illness and protect public health. Three areas of limitation have been identified with current food safety inspection approaches, including comprehensiveness, coherence and bias. This paper presents a model - hereafter called the Barnes model - for food safety inspection that is targeted at addressing the limitations of current practice. This study evaluates whether the Barnes model can be effectively implemented into food safety regulatory practice.Design/methodology/approachTraining materials were created and provided to EHPs to support them interpreting and implementing the Barnes model in field trials. Field observations and interviews were then conducted to evaluate the efficacy and practicability of utilizing the Barnes model and to identify barriers to implementation.FindingsThis pilot research found that EHPs were able to adopt the Barnes model into their practice, although implementation could be hampered by key barriers such as incompatible legislative frameworks, unsuited performance measurements for EHPs and lack of oversight from a governing body.Originality/valueThe findings from this study will inform the future of food safety regulatory practice by determining that the Barnes model can be adopted and implemented by EHPs into their regulatory practice, setting the necessary foundations for further research on the effectiveness of the Barnes model as a health protection measure.

IntroductionThe persistence of opportunistic premise plumbing pathogens (OPPPs) in drinking water plumbing systems poses a significant public health risk that is receiving increasing attention yet remains poorly understood. This study investigated the co-occurrence of OPPPs and the influence of building infrastructure properties on their prevalence.MethodsDrinking water and biofilm samples were collected from hospitals and private residences across Australia to investigate the abiotic and biotic factors contributing to the growth and proliferation of OPPPs.ResultsQuantitative polymerase chain reaction assays revealed that 41% of samples tested positive for Pseudomonas aeruginosa, 26% for Staphylococcus aureus, 26% for Legionella spp., 24% for Legionella pneumophila, and 14% for Acinetobacter baumannii. Furthermore, free-living amoebae, including Vermamoeba vermiformis (46%) and Acanthamoeba spp. (25%), were frequently detected, with Acanthamoeba spp. demonstrating a significant positive correlation with all bacterial OPPPs. Overall, results indicated a statistically higher prevalence of OPPPs in residential properties and in biofilms. However, building characteristics, including stagnation, hot water system type, and building age, had inconsistent influences on individual OPPP prevalence.DiscussionThese results emphasize the need to incorporate risk assessments regarding the complex factors within the premise plumbing environment that contribute to pathogen persistence, to inform evidence based targeted preventative strategies for at-risk populations. These findings are particularly critical for individuals receiving healthcare at home, as inconsistent water treatment and monitoring in residential settings may increase their risk of exposure to OPPPs.