Can free chlorine residuals entering building plumbing systems really be maintained to prevent microbial growth?

Secondary disinfection aims to prevent microbial regrowth during distribution by maintaining disinfectant residuals in water systems. However, multi-factorial interactions contribute to free chlorine decay in distribution systems, and even more so in building plumbing. Assembling 1737 samples from nine large institutional buildings, a meta-analysis was conducted to determine whether building managers can actively rely on incoming free chlorine residuals to prevent in-building microbial amplification. Findings showed that free chlorine concentrations in first draws met the 0.2 mg/L common guide level in respectively 26 %, 6 % and 2 % of cold, tepid and hot water samples, whereas flushing for 2-60 min only significantly increased this ratio in cold water (83 %), without reaching background levels found in service lines. Free chlorine was significantly but weakly (R≤ 0.2) correlated to adenosine triphosphate, heterotrophic plate count and total and intact cell counts, thus evidencing that residuals contributed to decreased culturable and viable biomass. Detection of culturable Legionella pneumophila spanning over a 4-log distribution solely occurred when free chlorine levels were below 0.2 mg/L, but no such trend could be distinguished clearly for culturable Pseudomonas aeruginosa. Water temperatures below 20 °C and >60 °C also completely prevented L. pneumophila detection. Overall, the majority of elevated microbial counts were measured in distal sites and in tepid and hot water, where free chlorine is less likely to be present due to stagnation and increased temperature. Therefore, building managers cannot solely rely on this chemical barrier to mitigate bacterial growth in bulk water.

Direct evidence of microbiological water quality changes on bacterial quantity and community caused by plumbing system.

Drinking water quality deteriorates from treatment plant to customer taps, especially in the plumbing system. There is no direct evidence about what the differences are contributed by plumbing system. This study compared the water quality in the water main and at customer tap by preparing a sampling tap on the water main. The biomass was quantified by adenosine triphosphate (ATP) and the microbial community was profiled by 454 pyrosequencing. The results showed that in distribution pipes, biofilm contributed >94% of the total biomass, while loose deposits showed little contribution (< 2%) because of the low amount of loose deposits. The distribution of biological stable water had minor effects on the microbiocidal water quality regarding both quantity (ATP 1 ng/L vs. 1.7 ng/L) and community of the bacteria. Whereas the plumbing system has significant contribution to the increase of active biomass (1.7 ng/L vs. 2.9 ng/L) and the changes of bacterial community. The relative abundance of Sphingomonas spp. at tap (22%) was higher than that at water main (2%), while the relative abundance of Pseudomonas spp. in tap water (15%) was lower than that in the water from street water main (29%). Though only one location was prepared and studied, the present study showed that the protocol of making sampling tap on water main offered directly evidences about the impacts of plumbing system on tap water quality, which makes it possible to distinguish and study the processes in distribution system and plumbing system separately.

Prevalence of opportunistic pathogens in a school building plumbing during periods of low water use and a transition to normal use.

The spread of opportunistic pathogens via building water supply and plumbing is of public health concern. This study was conducted to better understand microbial water quality changes in a LEED-certified school building during low water use (Summer) and normal water use (Autumn). The copper plumbed building contained water saving devices, a hot water recirculation system, and received chloraminated drinking water from a public water system. Three separate sampling events were conducted during the summer break inside the building and another three sampling events were conducted after the school returned to session. Using quantitative PCR, Legionella spp. were detected in all water samples, followed by Mycobacterium spp. (99%). Mycobacterium avium (75%) and Acanthamoeba spp. (17.5%) throughout the building water system. Legionella pneumophila and Naegleria fowleri were not detected in any of the samples. The mean concentrations of Legionella spp., Mycobacterium spp., Mycobacterium avium, and Acanthamoeba spp. detected in water samples were 3.9, 5.7, 4.7, and 2.8 log10 gene copies per 100 ml, respectively. There was a statistically significantly difference in the mean concentrations of Legionella spp., Mycobacterium spp. and M. avium gene markers in water samples between school breaks and when school was in session. Cultivable Legionella were also detected in water samples collected during periods of low water use. This study highlights the need for routine proactive water quality testing in school buildings to determine the extent of drinking water quality problems associated with plumbing and direct action to remediate microbial colonization.

Los nuevos retos en la ingeniería sanitaria en Perú: Pandemia COVID-19 y enseñanza remota / The new challenges in sanitary engineering in Peru: COVID-19 pandemic and remote teaching

La Ingeniería Sanitaria surge como una rama de la ingeniería que involucra tanto materias propias de la ingeniería tales como: matemáticas, física, química hidráulica o mecánica, como aquellas relacionada con la medicina y la higiene, tales como la microbiología y conservación. Tiene como función principal crear y fomentar condiciones de salubridad en las poblaciones siendo vigilante de las aguas, el aire y la tierra, evitando que la contaminación alcance a los seres humanos. En Perú, la ingeniería sanitaria se creó como un apéndice de la ingeniería civil, pero pronto tomó el lugar merecido, declarándose una carrera de ingeniería independiente. Actualmente, la Ingeniería sanitaria es la encargada de llevar agua potabilizada a la población, y tratar las aguas servidas. Por otra parte, con la llegada del SARS-CoV-2, el mundo fue sacudido, y una situación de pandemia emergió, lo que hizo que los diferentes países tomasen las acciones necesarias, tal como sucedió con el Perú. Allí, la Ingeniería Sanitaria, accionó sus funciones, buscando la potabilización del agua de consumo. En estos tiempos de pandemia, también determinaron el resguardo de la población, lo que fomentó la educación remota. En el caso de la Ingeniería Sanitaria, los laboratorios presenciales y convencionales fueron sustituidos por laboratorios virtuales y remotos, lo cual permitió que la educación continuase sin contratiempos(AU)

Sanitary Engineering emerges as a branch of engineering that involves both engineering subjects such as: mathematics, physics, hydraulic or mechanical chemistry, as well as those related to medicine and hygiene, such as microbiology and conservation. Its main function is to create and promote healthy conditions in the populations, being vigilant of the waters, the air and the land, preventing contamination from reaching human beings. In Peru, sanitary engineering was created as an appendix to civil engineering, but it soon took its deserved place, declaring itself an independent engineering career. Currently, Sanitary Engineering is in charge of bringing drinking water to the population, and treating wastewater. On the other hand, with the arrival of SARS-CoV-2, the world was shaken, and a pandemic situation emerged, which made the different countries take the necessary actions, as happened with Peru. Over there, the Sanitary Engineering, activated its functions, seeking the potabilization of drinking water. In these times of pandemic, they also determined the protection of the population, which promoted remote education. In the case of Sanitary Engineering, face-to-face and conventional laboratories were replaced by virtual and remote laboratories, which allowed education to continue without setbacks(AU)

Eco-responsibility in the operating theater: An urgent need for organizational transformation.

Factors associating environmental degradation with human health have shown that air pollution is a source of morbi-mortality throughout the world. Unfortunately, hospitals are themselves "silent polluters". As healthcare professionals, we are the guarantors not only of quality of patient care, but also of proper hospital conduct. The aim of this attempt at clarification is to outline what can be done in the operating theater to reduce the environmental impact of the treatments we administer. Our recommendations will go above and beyond regulatory frameworks and draw upon daily practice concerning waste management, energy consumption, utilization of anesthetic agents and multiple forms of waste. A number of French and international pilot experimentations have been carried out and could strongly contribute to the modification of clinical practices with a societal impact, at a time when ecology has become one of the main preoccupations of our fellow citizens.

Know your enemy: Unexpected, pervasive and persistent viral and bacterial contamination of primary cell cultures.

In biomedical research, cell culture contamination is one of the main culprits of experimental failure. Contamination sources and concomitant remedies are numerous and challenging to manage. We herein describe two cases of uncommon contamination of cell cultures that we encountered, and the successful determination and eradication strategies. The first case describes the infection with human adenovirus C that originated from pharyngeal tonsils used for isolation of primary tonsillar epithelial cells. It is known that viral contamination of in vitro cell cultures can occur symptomless and is therefore difficult to identify. The contamination was pervasive and persistent, as it was widely spread in flow cabinets and apparatus, and has caused a serious delay to our research projects and the inevitable loss of valuable (patient-derived) cell sources. Eradication was successful by formalin gas sterilization of the flow cabinet and elimination of all infected cell lines from our biobank after PCR-guided determination. Secondly, we encountered a spore-forming bacterium, namely Brevibacillus brevis, in our cell culture facility. This bacterium originated from contaminated tap water pipes and spread via regular aseptic culture techniques due to survival of the bacterial spores in 70% ethanol. B brevis overgrew the cultures within a few days after seeding of the primary cells. Chlorine solution effectively killed this spore-forming bacterium. Both cases of contamination were identified using DNA sequencing which enabled the deployment of targeted aseptic techniques for the elimination of the persistent contamination.

Comparison of the characteristics of hot tap water scalds and other scalds in Germany.

BACKGROUND/AIM: Mortality associated with hot tap water scalds remains significant, owing to a lack of up-to-date regulations on tap water temperature. We aimed to evaluate the effect of hot tap water scalds on patients admitted to our adult burn intensive care unit (BICU), and compare them to those with other scald types. METHODS: We enrolled patients treated for scalds at the BICU of Cologne-Merheim Medical Center from 1989 to 2014, and retrospectively analyzed their age, sex-specific differences, characteristics, length of hospital stay, number of operations, and mortality. Patients were categorized into two groups: patients with hot tap water scalds and those with all other types of scalds. RESULTS: A total of 333 patients were enrolled. In 23.4% (n=78) of the cases, the scalds were associated with hot tap water. Such injuries were more commonly observed in older men than women. Hot tap water scalds involved a significantly higher total burned surface area (TBSA) than other scalds, with TBSA values of 24.0% and 15.9% for men, and 21.8% and 10.9% for women, respectively. Hot tap water scald patients had a greater number of surgeries and longer BICU stays (27.8 days vs 9.1 days), and significantly higher mortality values (30.8% (n=24) vs 4.7% (n=12)) than those with the other scald types. CONCLUSIONS: Hot water scalds are associated with large TBSAs, long stays in the BICU, and worse outcomes compared to the other scald types.

Diversidad de especies de micobacterias no tuberculosas aisladas en ambientes acuáticos de la ciudad de General Pico, La Pampa, Argentina / Species diversity of non-tuberculous mycobacteria isolated from aquatic environments of General Pico city, Province of La Pampa (Argentina)

Las micobacterias no tuberculosas (MNT) no solo se estudian por su importancia como patógenos oportunistas, sino también por sus aplicaciones en biotecnología y biorremediación. Nuestro objetivo fue determinar la presencia de micobacterias en los distintos hábitats acuáticos de la ciudad de General Pico (provincia de La Pampa), así como su diversidad. Los porcentajes de muestras positivas a micobacterias fueron los siguientes: 37,5% en el sistema de distribución de agua de red, 32,6% en el acuífero que abastece dicho sistema, 36,8% en el agua proveniente de las precipitaciones, 53,1% en los humedales del área de influencia, 80% en los natatorios cubiertos y 33,3% en las fuentes decorativas ubicadas en plazas públicas. De los 90 aislamientos de MNT obtenidos el 8,9% no logró ser identificado a nivel de especie con los métodos utilizados, que incluyeron pruebas fenotípicas y métodos moleculares. Las especies más frecuentemente aisladas fueron Mycobacterium fortuitum y Mycobacterium gordonae. Algunas especies identificadas han sido reportadas en casos de micobacteriosis en nuestro país, entre ellas M. fortuitum, M. gordonae, M. intracellulare, M. vaccae, M. lentiflavum y M. nonchromogenicum. No se aislaron MNT en muestras de agua de red con concentraciones de cloro activo residual mayores de 0,8mg/l, mientras que en los natatorios la presencia de hasta 1,5mg/l de cloro activo residual no fue una limitante para la proliferación de estos microorganismos. Se puede considerar que la incidencia de micobacterias en los ambientes acuáticos de General Pico es cercana al 35%, y que la presencia de estos microorganismos y su diversidad se ve afectada por el contacto con el hombre y sus actividades, como así también por la existencia de vida animal.

Non-tuberculous mycobacteria (NTM) are studied not only for their importance as emerging opportunistic pathogens but also for their applications in biotechnology and bioremediation. Our aim was to determine the occurrence and diversity of mycobacteria in different aquatic habitats of General Pico city, Province of La Pampa. The percentage of samples with positive cultures for mycobacteria were the following: 37.5% recovered from the water supply distribution system; 32.6% from the aquifer that supplies water to the distribution system; 36.8% from rain water; 53.1% from the two wetlands in the area of influence; 80% from indoor swimming pools; and 33.3% from water fountains in downtown public squares. Of the 90 NTM isolates, 8.9% could not be identified at the species level with any of the used methods, phenotypic tests and molecular methods. Mycobacterium fortuitum and Mycobacterium gordonae were the most frequently isolated species. Some of the identified species such as, M. fortuitum, M. gordonae, M. intracellulare, M. vaccae, M. lentiflavum and M. nonchromogenicum, have been reported in cases of mycobacteriosis in Argentina. Mycobacteria with values higher than 0.8mg/ml of residual active chlorine were not recovered from the drinking water supply network, whereas in the swimming pools the presence of up to 1.5 mg/l was not a constraint. Based on our results, the presence of mycobacteria in aquatic environments is close to 35% and their occurrence and diversity is affected both by contact with man and his activities as well as by the existence of animal life.

POU water filters effectively reduce lead in drinking water: a demonstration field study in flint, Michigan.

A field study was conducted to test the effectiveness of faucet-mounted point of use (POU) water filters for removing high concentrations of lead in drinking water from premise plumbing sources and lead service lines (LSL). These filters were concurrently certified for total lead removal under NSF/ANSI Standard 53 (NSF/ANSI-53) and for fine particulate (Class I) reduction under NSF/ANSI Standard 42 (NSF/ANSI-42). In 2016, filtered and unfiltered drinking water samples were collected at over 345 locations in Flint, Michigan. Over 97% of filtered water samples contained lead below 0.5 µg/L. The maximum lead concentration in filtered water was 2.9 µg/L, well below the bottled water standard. The effectiveness of the POU activated carbon block filters in reducing lead concentrations, even above the 150 µg/L NSF/ANSI-53 challenge standard, is likely related to trapping particles due to the small effective pore size of the filters, in addition to ion-exchange or sorption removal of soluble lead. Properly installed and maintained POU filters, certified under both NSF/ANSI-53 (for total lead) and NSF/ANSI-42 (for fine particulate), can protect all populations, including pregnant women and children, by reducing lead in drinking water to levels that would not result in a significant increase in overall lead exposure.

Control inalámbrico de mesa quirúrgica desde dispositivo móvil / Wireless control of operating tables from a mobile device

Para la mayoría de las mesas quirúrgicas del hospital, el proveedor ya no comercializa controles remotos compatibles, lo cual implicaría un gasto importante para su actualización o renovación. Para evitar dicho gasto, se diseñó un control inalámbrico para manejar los movimientos de las mesas quirúrgicas a través de un dispositivo móvil.

The provider no longer provides compatible remote controls for most of operating tables at the hospital, which would imply an important expense for their upgrading or renewal. In order to avoid that expenditure, a wireless control was designed to improve operating table movements from a mobile device.

A new scenario of lead contamination in potable water distribution systems: Galvanic corrosion between lead and stainless steel.

Lead pipe has been banned for distributing drinking water in the 1980s and partial replacement of lead pipes with stainless steel pipes has been practiced in many Asian countries. Due to the different potentials of lead and stainless steel, galvanic corrosion may take place. The extent of lead release and effects of water chemistry on this process, however, are largely unknown. The objectives of this study are to characterize lead release resulting from galvanic connection between lead and stainless steel, the effects of pH, chloride and sulfate concentrations on this process, and the effectiveness of using orthophosphate to mitigate this problem. The experiments were conducted by connecting aged lead pipes to stainless steel fittings and placing the couple in different water conditions. The results of this study demonstrated that lead release significantly accelerated when lead and stainless steel were galvanically connected and the rate of lead release accelerated with decreasing pH and increasing chloride-to-sulfate mass ratio (CSMR). Orthophosphate could effectively reduce lead release but CSMR needs to be considered since water with a higher CSMR still caused more lead release when galvanic corrosion took place.

Electricity generation from landfill gas in Turkey.

Landfill gas (LFG)-to-energy plants in Turkey were investigated, and the LFG-to-energy plant of a metropolitan municipal landfill was monitored for 3 years. Installed capacities and actual gas engine working hours were determined. An equation was developed to estimate the power capacity for LFG-to-energy plants for a given amount of landfilled waste. Monitoring the actual gas generation rates enabled determination of LFG generation factors for Turkish municipal waste. A significant relationship (R = 0.524, p < 0.01, two-tailed) was found between the amounts of landfilled waste and the ambient temperature, which can be attributed to food consumption and kitchen waste generation behaviors influenced by the ambient temperature. However, no significant correlation was found between the ambient temperature and the generated LFG. A temperature buffering capacity was inferred to exist within the landfill, which enables the anaerobic reactions to continue functioning even during cold seasons. The average LFG and energy generation rates were 45 m3 LFG/ton waste landfilled and 0.08 MWhr/ton waste landfilled, respectively. The mean specific LFG consumption for electricity generation was 529 ± 28 m3/MWhr. IMPLICATIONS: The paper will be useful for local authorities who need to manage municipal waste by using landfills. The paper will also be useful for investors who want to evaluate the energy production potential of municipal wastes and the factors affecting the energy generation process mostly for economical purposes. Landfills can be regarded as energy sources and their potentials need to be investigated. The paper will also be useful for policymakers dealing with energy issues. The paper contains information on real practical data such as engine working hours, equation to estimate the necessary power for a given amount of landfilled waste, and son on.

Eliasz Cynamon e o Programa do Rio Doce (Sesp): contribuição de fontes para a história das ações de saúde e saneamento no Brasil, 1952-1960 / Eliasz Cynamon and the Rio Doce Program (SESP): contribution of sources to the history of health and sanitation actions in Brazil, 1952-1960

Resumo Apresenta pesquisa acerca da atuação de Szachna Eliasz Cynamon no Programa Vale do Rio Doce (1952-1960). Privilegiamos como fonte de consulta os acervos dos departamentos de Arquivo e Documentação e de Saneamento e Saúde Ambiental, na Fiocruz, e o ainda pertencente à família. Na época, a região contava com altos índices de malária. Cynamon, nascido na Polônia e imigrado ainda criança nos anos 1930 para o Brasil, onde se graduaria em engenharia sanitária, foi contratado para atuar em Colatina (ES) e em Governador Valadares (MG), entre 1952 e 1960. Nessas localidades, dedicou-se ao tratamento e abastecimento de água e esgoto sanitário, além de realizar cursos de educação sanitária para a população local, como parte de acordo de cooperação Brasil-EUA.

Abstract Research into the work of Szachna Eliasz Cynamon in the Rio Doce Valley Program (1952-1960) is presented. The key sources are from the Department of Archives and Documentation and the Department of Sanitation and Environmental Health at Fiocruz, as well as the family's own archive. At the time, the rates of malaria in the region were high. Born in Poland, Cynamon migrated to Brazil in the 1930s while still a child, where he graduated in sanitary engineering. He was hired to work in Colatina (Espírito Santo) and Governador Valadares (Minas Gerais) between 1952 and 1960, focusing on sewage and water treatment and supply, while also holding sanitation education courses for the local people as part of a Brazil-USA cooperation agreement.

Prevalence of Infection-Competent Serogroup 6 Legionella pneumophila within Premise Plumbing in Southeast Michigan.

Coinciding with major changes to its municipal water system, Flint, MI, endured Legionnaires' disease outbreaks in 2014 and 2015. By sampling premise plumbing in Flint in the fall of 2016, we found that 12% of homes harbored legionellae, a frequency similar to that in residences in neighboring areas. To evaluate the genetic diversity of Legionella pneumophila in Southeast Michigan, we determined the sequence type (ST) and serogroup (SG) of the 18 residential isolates from Flint and Detroit, MI, and the 33 clinical isolates submitted by hospitals in three area counties in 2013 to 2016. Common to one environmental and four clinical samples were strains of L. pneumophila SG1 and ST1, the most prevalent ST worldwide. Among the Flint premise plumbing isolates, 14 of 16 strains were of ST367 and ST461, two closely related SG6 strain types isolated previously from patients and corresponding environmental samples. Each of the representative SG1 clinical strains and SG6 environmental isolates from Southeast Michigan infected and survived within macrophage cultures at least as well as a virulent laboratory strain, as judged by microscopy and by enumerating CFU. Likewise, 72 h after infection, the yield of viable-cell counts increased >100-fold for each of the representative SG1 clinical isolates, Flint premise plumbing SG6 ST367 and -461 isolates, and two Detroit residential isolates. We verified by immunostaining that SG1-specific antibody does not cross-react with the SG6 L. pneumophila environmental strains. Because the widely used urinary antigen diagnostic test does not readily detect non-SG1 L. pneumophila, Legionnaires' disease caused by SG6 L. pneumophila is likely underreported worldwide.IMPORTANCEL. pneumophila is the leading cause of disease outbreaks associated with drinking water in the United States. Compared to what is known of the established risks of colonization within hospitals and hotels, relatively little is known about residential exposure to L. pneumophila One year after two outbreaks of Legionnaires' disease in Genesee County, MI, that coincided with damage to the Flint municipal water system, our multidisciplinary team launched an environmental surveillance and laboratory research campaign aimed at informing risk management strategies to provide safe public water supplies. The most prevalent L. pneumophila strains isolated from residential plumbing were closely related strains of SG6. In laboratory tests of virulence, the SG6 environmental isolates resembled SG1 clinical strains, yet they are not readily detected by the common diagnostic urinary antigen test, which is specific for SG1. Therefore, our study complements the existing epidemiological literature indicating that Legionnaires' disease due to non-SG1 strains is underreported around the globe.

Unusual case of hypotenar Hammer Syndrome and carpal tunnel syndrome association.

BACKGROUND AND AIM OF THE WORK: Hypothenar Hammer Syndrome is a relatively rare disease process caused by repetitive stress or injury to the hypothenar eminence leading to chronic injury to the ulnar artery. Our study reports an unusual case. METHODS: A 57 years old Plumber presented in April 2016 with a history of constant pain and recurrent paresthesia involving the fingers of the right hand for several months, over the previous 1 year, his hand had become more intolerant of exposure to cold temperatures. Angio-RNM and electromyography were performed and showed a severe double compression of ulnar and median nerve and an ulnar artery deformity without thrombosis. Surgery was performed under sedation and axillary anesthesia. RESULTS: After surgery patient' symptoms immediately improved, and within a few months, his hand had normalized. CONCLUSION: Hypothenar Hammer Syndrome is a rare disease process which manifests in certain occupations and activities that put undue stress on the hypothenar area. Furthermore, the carpal tunnel syndrome, a pressure damage of the median nerve, caused by repetitive manual tasks with flexion and extension of wrist has been added as well as hypothenar hammer syndrome which are vascular damages of hand caused by shock-type application of force.

9 Caderno de Pesquisa em Engenharia de Saúde Pública / 9th Research Book in Public Health Engineering

O Caderno apresenta os resumos executivos de sete pesquisas financiadas pela Funasa, resultantes dos Editais 01/2007 e 01/2011 do Programa de Pesquisa em Saúde e Saneamento. As pesquisas são nas áreas de gestão em engenharia de saúde pública, resíduos sólidos urbanos e abastecimento de água, temas relevantes para o desenvolvimento do saneamento básico no País, contribuindo para a missão da Funasa de "promover a saúde pública e a inclusão social por meio de ações de saneamento e saúde ambiental". Na área de gestão em engenharia de saúde pública, foram desenvolvidas quatro pesquisas: Gestão de serviços de abastecimento de água e esgotamento sanitário: a participação social em três modelos institucionais no Espírito Santo; Metodologias para fortalecimento do controle social na gestão em saneamento; Análise do Serviço Integrado de Saneamento Rural ­ SISAR, do Ceará, em sua dimensão político-institucional ; e Instrumentos metodológicos para estimular a formação de consórcios públicos voltados para gestão integrada dos serviços de saneamento. Na área de resíduos sólidos urbanos, foi desenvolvida a pesquisa: Coleta seletiva: modelos de gestão com e sem inclusão de catadores, vantagens e desvantagens na perspectiva da sustentabilidade. Na área de abastecimento de água, foram desenvolvidas duas pesquisas: Tratamento de águas com excesso de ânions fluoreto e nitrato utilizando HDLS, argilas e zeólitas como adsorventes maiores; e Sistemas de tratamento para desfluoretação parcial de águas subterrâneas com presença de flúor superior à estabelecida na Portaria MS nº 2.914/2011.

Biofilm forming ability of Sphingomonas paucimobilis isolated from community drinking water systems on plumbing materials used in water distribution.

Sphingomonas paucimobilis, an oligotroph, is well recognized for its potential for biofilm formation. The present study explored the biofilm forming ability of a strain isolated from municipal drinking water on plumbing materials. The intensity of biofilm formation of this strain on different plumbing materials was examined by using 1 × 1 cm2 pieces of six different pipe materials, i.e. polyvinyl chloride (PVC), polypropylene (PP), polyethylene (PE), aluminium (Al), copper (Cu) and rubber (R) and observing by staining with the chemical chromophore, Calcofluor. To understand whether biofilm formation occurs under flow through conditions, a laboratory-scale simulated distribution system, comprised of the above materials was fabricated. Biofilm samples were collected from the designed system at different biofilm ages (10, 40 and 90 hours old) and enumerated. The results indicated that the biofilm formation occurred on all plumbing materials with Cu and R as exceptions. The intensity of biofilm formation was found to be maximum on PVC followed by PP and PE. We also demonstrated the chemical chromophore (Calcofluor) successfully for rapid and easy visual detection of biofilms, validated by scanning electron microscope (SEM) analysis of the plumbing materials. Chlorination has little effect in preventing biofilm development.