AMR and Covid-19 on the Frontline: A Call to Rethink War, WASH, and Public Health.

This Viewpoint calls for a greater understanding of the role that water plays in the transmission of anti-microbial resistance and covid-19 in protracted urban armed conflict, in order to develop a 'pathogen-safe' practice. It argues that dealing with the twin threats is difficult enough in the best of circumstances, and is so little understood in war zones that surgeons and water engineers now question if their practice does more harm than good. Experience suggests that the known transmission routes are complicated by a great number of factors, including the entry of heavy metals through bullets in patients' wounds, hospital over-crowding, mutation in treated water or wastewater, and other threats which endure long after the bombing has stopped. The skeleton research agenda proposes greater sewage surveillance, testing of phages and monitoring of treatment designed to dispel or substantiate these assertions.

Research to Move Toward Evidence-Based Recommendations for Lead Service Line Disclosure Policies in Home Buying and Home Renting Scenarios.

Lead service lines (LSLs)-lead pipes connecting the water main under the street to a building's plumbing-contribute an estimated 50% to 75% of lead in tap water when they are present. Although Congress banned lead in plumbing materials in 1986, over 6 million LSLs remain in homes across the United States today. This paper summarizes three different home buying or renting scenario-based experimental studies used to evaluate disclosure styles, to assess if these influenced respondents' perceived risk of the LSL in a home, and their willingness to act. In renting scenarios, having landlords disclose the presence of an LSL, but also provide water test results showing lead levels below the EPA's lead action level resulted in lower levels of perceived risk, and of willingness to act. In seller-disclosure home buying scenarios, levels of perceived risk and willingness to act were consistently high, and three different disclosure styles did not differentially influence those outcomes. In home inspector-disclosure home buying scenarios, levels of perceived risk and willingness to act were high, but having explicit recommendations to replace LSLs and/or information about risk did not further influence those outcomes. In some cases, including the specific recommendations backfired. Implications for policy and regulation are discussed.

Evaluation of lead release potential of new premise plumbing materials.

Premise plumbing materials such as pipes, valves, fittings, and faucets are made of various materials, including plastic, stainless steel, copper, and brass/bronze. Although lead pipe has been banned for its use in drinking water supply by most countries in the 1980s, lead is still commonly used as an additive in many plumbing materials for its flexibility and malleability. Certified leaching tests for plumbing materials are usually conducted using relatively mild solutions over short periods which may not reveal the true risk of lead exposure when these materials are used. The objective of this study is to investigate the extents of lead release from commonly used premise plumbing materials into drinking water. The maximum lead leaching potential for pluming material was operationally determined using high strength acidic EDTA solutions (pH 4, EDTA = 100 mg/L) for a stagnation time of 3 days for a total period of up to 1 month. Lead leaching from each plumbing material was also evaluated using reconstituted tap water. Brass- and bronze-based plumbing materials were found to release dangerous levels of lead. Surface lead weight percentage obtained using SEM-EDX and lead weight percentages of the material body obtained using strong acid digestion were found to positively correlate with lead release. A re-examination of the appropriateness of current certified leaching tests and a more stringent regulation on the use of lead as an additive for plumbing materials should be considered.

Case study: Fixture water use and drinking water quality in a new residential green building.

Residential plumbing is critical for the health and safety of populations worldwide. A case study was conducted to understand fixture water use, drinking water quality and their possible link, in a newly plumbed residential green building. Water use and water quality were monitored at four in-building locations from September 2015 through December 2015. Once the home was fully inhabited average water stagnation periods were shortest at the 2nd floor hot fixture (90 percentile of 0.6-1.2 h). The maximum water stagnation time was 72.0 h. Bacteria and organic carbon levels increased inside the plumbing system compared to the municipal tap water entering the building. A greater amount of bacteria was detected in hot water samples (6-74,002 gene copy number/mL) compared to cold water (2-597 gene copy number/mL). This suggested that hot water plumbing promoted greater microbial growth. The basement fixture brass needle valve may have caused maximum Zn (5.9 mg/L), Fe (4.1 mg/L), and Pb (23 µg/L) levels compared to other fixture water samples (Zn ≤ 2.1 mg/L, Fe ≤ 0.5 mg/L and Pb ≤ 8 µg/L). At the basement fixture, where the least amount of water use events occurred (cold: 60-105, hot: 21-69 event/month) compared to the other fixtures in the building (cold: 145-856, hot: 326-2230 event/month), greater organic carbon, bacteria, and heavy metal levels were detected. Different fixture use patterns resulted in disparate water quality within a single-family home. The greatest drinking water quality changes were detected at the least frequently used fixture.

Pathogen cross-transmission via building sanitary plumbing systems in a full scale pilot test-rig.

The WHO Consensus Document on the epidemiology of the SARS epidemic in 2003, included a report on a concentrated outbreak in one Hong Kong housing block which was considered a 'super-spreading event'. The WHO report conjectured that the sanitary plumbing system was one transmission route for the virus. Empty U-traps allowed the aerosolised virus to enter households from the sewerage system. No biological evidence was presented. This research reports evidence that pathogens can be aerosolised and transported on airstreams within sanitary plumbing systems and enter buildings via empty U-traps. A sanitary plumbing system was built, representing two floors of a building, with simulated toilet flushes on the lower floor and a sterile chamber with extractor fan on the floor above. Cultures of a model organism, Pseudomonas putida at 106-109 cfu ml-1 in 0·85% NaCl were flushed into the system in volumes of 6 to 20 litres to represent single or multiple toilet flushes. Air and surface samples were cultured on agar plates and assessed qualitatively and semi-quantitatively. Flushing from a toilet into a sanitary plumbing system generated enough turbulence to aerosolise pathogens. Typical sanitary plumbing system airflows (between 20-30 ls-1) were sufficient to carry aerosolised pathogens between different floors of a building. Empty U-traps allowed aerosolised pathogens to enter the chamber, encouraging cross-transmission. All parts of the system were found to be contaminated post-flush. Empty U-traps have been observed in many buildings and a risk assessment indicates the potential for high risk cross-transmission under defect conditions in buildings with high pathogen loading such as hospitals. Under defective conditions (which are not uncommon) aerosolised pathogens can be carried on the airflows within sanitary plumbing systems. Our findings show that greater consideration should be given to this mode of pathogen transmission.

Effective testing for mobile units.

In February's HEJ--in the first 'half' of a two-part article focusing on the design, installation, and testing of medical gas systems for mobile units, medical gas specialist, Geoff Dillow, examined some of the design and construction limitations particular to such units, and how these can the impact on the equipment's compliance with HTM guidance. In this second part, he considers some of the key requirements for effective testing of mobile unit medical gas installations.

Modelling characteristics to predict Legionella contamination risk - Surveillance of drinking water plumbing systems and identification of risk areas.

For the surveillance of drinking water plumbing systems (DWPS) and the identification of risk factors, there is a need for an early estimation of the risk of Legionella contamination within a building, using efficient and assessable parameters to estimate hazards and to prioritize risks. The precision, accuracy and effectiveness of ways of estimating the risk of higher Legionella numbers (temperature, stagnation, pipe materials, etc.) have only rarely been empirically assessed in practice, although there is a broad consensus about the impact of these risk factors. We collected n = 807 drinking water samples from 9 buildings which had had Legionella spp. occurrences of >100 CFU/100mL within the last 12 months, and tested for Legionella spp., L. pneumophila, HPC 20°C and 36°C (culture-based). Each building was sampled for 6 months under standard operating conditions in the DWPS. We discovered high variability (up to 4 log(10) steps) in the presence of Legionella spp. (CFU/100 mL) within all buildings over a half year period as well as over the course of a day. Occurrences were significantly correlated with temperature, pipe length measures, and stagnation. Logistic regression modelling revealed three parameters (temperature after flushing until no significant changes in temperatures can be obtained, stagnation (low withdrawal, qualitatively assessed), pipe length proportion) to be the best predictors of Legionella contamination (>100 CFU/100 mL) at single outlets (precision = 66.7%; accuracy = 72.1%; F(0.5) score = 0.59).

[The necessity of new approaches to the elaboration of the projects for the sanitary (mountainous sanitary) protection districts around the therapeutic and health-promotion facilities, health resorts and their natural medical resources].

The international experience gained during the past two centuries indicates that the most efficient and rational way to ensure the protection of the territories occupied by the therapeutic and health-promotion facilities, spa centres, and health resorts together with their natural medical resources is to set up sanitary (mountainous sanitary) protection districts or zones along the perimeter of these territories. Beginning from 2000, numerous changes and amendments have been annually introduced in the Russian legislation intended to ensure efficacious control over the rational exploitation of the territories of therapeutic and health-promotion value and their natural medical resources. These initiatives have negative effect on the activities of these organizations and the quality of the services they are expected to provide. Taken together these effects lead to the degradation of the spa and health resort business. Bearing in mind the current conditions for economic activities, it is proposed, in contrast to the former global approach, to envisage in the aforementioned projects the establishment of the sanitary (mountainous sanitary) protection districts or zones and determine their borders based on the results of the assessment of their potential for the protection of therapeutic factors and other valuable resources. Equally important is the maximum reduction of the areas of the second and third zones taking into account their relevant objective characteristics. In certain cases, the protective district may coincide with the second zone. As far as the federal health resorts and large territories of special health-promotion value are concerned, some of them may have two or more sanitary (mountainous sanitary) protection districts. Both the owners and the users of these territories should be provided the necessary and sufficient possibilities for the rational nature use at the grounds and in the adjacent water areas suitable for the development of health resort business in the conditions guaranteed by the national legislation.

Clustering analysis of water distribution systems: identifying critical components and community impacts.

Large water distribution systems (WDSs) are networks with both topological and behavioural complexity. Thereby, it is usually difficult to identify the key features of the properties of the system, and subsequently all the critical components within the system for a given purpose of design or control. One way is, however, to more explicitly visualize the network structure and interactions between components by dividing a WDS into a number of clusters (subsystems). Accordingly, this paper introduces a clustering strategy that decomposes WDSs into clusters with stronger internal connections than external connections. The detected cluster layout is very similar to the community structure of the served urban area. As WDSs may expand along with urban development in a community-by-community manner, the correspondingly formed distribution clusters may reveal some crucial configurations of WDSs. For verification, the method is applied to identify all the critical links during firefighting for the vulnerability analysis of a real-world WDS. Moreover, both the most critical pipes and clusters are addressed, given the consequences of pipe failure. Compared with the enumeration method, the method used in this study identifies the same group of the most critical components, and provides similar criticality prioritizations of them in a more computationally efficient time.

Simplifying impact of urban development on sewer systems.

Linking urban development and urban drainage models is a more and more popular approach when impacts of pavement of urban areas on sewer system performance are evaluated. As such an approach is a difficult task, this is not a feasible procedure for everyday engineering practice. We propose an alternative method, based on a developed simple near-quadratic relationship, which directly translates change (increase or decrease) of paved area into a change in the return period (RP) of the design rainfall event or design rainfall intensity. This formula is simple to use and compatible with existing design guidelines. A further advantage is that the calculated design RP can also be used to communicate the impact of a change in impervious areas to stakeholders or the public community. The method is developed using a set of 250 virtual and two real-world case studies and hydrodynamic simulations. It is validated on a small catchment for which we compare system performance and redesigned pipe diameters. Of course such a simplification contains different uncertainties. But these uncertainties have to be seen in the context of overall uncertainties when trying to predict city development into the future. Hence it still is a significant advantage compared to today's engineering practice.

Assessing material flows in urban systems: an approach to maximize the use of incomplete data sets.

Data scarcity and uncertainty are the main limiting factors for an integral evaluation of the urban water and wastewater management system (WWMS) in developing countries. The present research shows an approach to use incomplete data sets to analyse the flows of water and nitrogen and to make an integral evaluation of the WWMS at a case study city. By means of data validation and model adaptations the use of literature values is kept at the minimum possible and so the current trends for water consumption and pollution in the city are identified. The material flows were calculated as central values with a certain confidence range and met the selected plausibility criteria. Thus, the first essential step needed to identify the challenges and opportunities of future improvement strategies at the WWMS of the city was possible.

Student-reported school drinking fountain availability by youth characteristics and state plumbing codes.

INTRODUCTION: Caloric intake among children could be reduced if sugar-sweetened beverages were replaced by plain water. School drinking water infrastructure is dictated in part by state plumbing codes, which generally require a minimum ratio of drinking fountains to students. Actual availability of drinking fountains in schools and how availability differs according to plumbing codes is unknown. METHODS: We abstracted state plumbing code data and used the 2010 YouthStyles survey data from 1,196 youth aged 9 through 18 years from 47 states. We assessed youth-reported school drinking fountain or dispenser availability and differences in availability according to state plumbing codes, sociodemographic characteristics, and area-level characteristics. RESULTS: Overall, 57.3% of youth reported that drinking fountains or dispensers in their schools were widely available, 40.1% reported there were only a few, and 2.6% reported that there were no working fountains. Reported fountain availability differed significantly (P < .01) by race/ethnicity, census region, the fountain to student ratio specified in plumbing codes, and whether plumbing codes allowed substitution of nonplumbed water sources for plumbed fountains. "Widely available" fountain access ranged from 45.7% in the West to 65.4% in the Midwest and was less common where state plumbing codes required 1 fountain per more than 100 students (45.4%) compared with 1 fountain per 100 students (60.1%) or 1 fountain per fewer than 100 students (57.6%). CONCLUSION: Interventions designed to increase consumption of water may want to consider the role of plumbing codes in availability of school drinking fountains.

PHE speaker outlines Porton Down findings.

Speaking at a recent Water Management Society conference, Ginny Moore, of Public Health England (PHE), described how the latest thinking, and the results of recent research and experience on minimising the risk of growth and spread of Pseudomonas aeruginosa bacteria in healthcare plumbing systems, as well as input from a number of leading plumbing product manufacturers, had informed the new guidance in the HTM 04-01 Addendum, 'Pseudomonas aeruginosa-- advice for augmented care units'. The guidance's publication, in March 2013, followed the death, just over a year earlier, of three young infants in the neonatal intensive care unit (NICU) at Belfast's Royal Jubilee Maternity Hospital (RJMH) from Pseudomonas aeruginosa-related infection, the source subsequently being identified as six handwashbasins.

Compliance work for food contact materials: feasibility of the legally required safety assessment of an epoxy/amine-based coating for domestic water pipe restoration.

Options were explored for fulfilling the legally required safety assessment for a widely applied epoxy/amine coating used for restoring corroded domestic drinking water supply systems. The coating was made up of two components mixed shortly before application, the first mainly consisting of bisphenol A diglycidyl ether (BADGE), the second of various amines. The analytically identified starting substances were all authorised, but only constituted a small proportion of the low molecular mass material left after curing and potentially migrating into water. Reaction products synthesised from constituents of the starting components (expected oligomers) could not be eluted from GC even after derivatisation, indicating that standard GC-MS screening would miss most potential migrants. They were detectable by size exclusion chromatography (SEC) after acetylation. HPLC with MS or fluorescence detection was possible for constituents including a BADGE moiety, but phenalkamines could not be detected with adequate sensitivity. Possibilities for determining long-term migration relevant for chronic toxicity are discussed. Analysis in water shortly after application of the coating overestimates migration if migration decreases over time and requires detection limits far out of reach. Analysis of a solvent extract of the coating is easier and provides an upper estimate of what could migrate into the drinking water over the years. However, to satisfy the regulatory requirements, components of the complex mixture need to be identified at lower proportions than those accessible. In vitro testing of the whole mixture for genotoxicity is expected to fail because of the required sensitivity and the glycidyl functions probably wrongly resulting in positive tests. The difficulties in dealing with this situation are discussed.