Untreated Surface Water as a Reservoir of Public Health Threats: A One Health Study from Northeast India

Fluidized ion exchange (FIX) to control NOM fouling in ultrafiltration

The occurrences of Cryptosporidium and Giardia in surface sources of drinking water in Tehran were monitored, using US EPA method 1623.1. The prevalence ratios (PR) of positive samples among other media (animal's stools, vegetables, and human's stools) were also estimated from literature data. The density of Giardia and Cryptosporidium in water samples were 0.129±0.069 cysts/L and 0.005±0.002 oocysts/L, respectively. Estimated PR in vegetables, animal stools, surface waters, and human stools were 6.65, 20.42, 21.05, and 4.28% for Cryptosporidium and 6.46, 17.13, 73.68, and 15.65% for Giardia, respectively. These reveal the importance of surface waters' and animal stools' roles in the prevalence of cryptosporidiosis and giardiasis in Tehran's population. Giardia's prevalence in untreated surface waters in Tehran was found 3.5 times as much as Cryptosporidium while this found 2.3 times on a global scale. Moreover, the prevalence of giardiasis to cryptosporidiosis infections in Tehran's human population was 3.65. These values could be a clue to attribute the infections to the occurrence of parasites in surface waters. Significant (p<0.05) associations were observed between rainfalls and presence of Giardia (r=0.62) and Cryptosporidium (r=0.60) in surface waters. In autumn, rainfalls can increase the parasites occurrences in surface waters. Significant (p<0.05) difference on the density of parasites was found between some seasons using Kruskal-Wallis and multiple comparison tests. A significant correlation (r=0.86) between Giardia and Cryptosporidium densities also confirms the common sources of pollution in surface waters. Findings suggest that untreated surface waters in Tehran may be a potential route of human exposure to protozoan parasites.

Untreated surface waters can be contaminated with a variety of bacteria, including , some of which can be pathogenic for both humans and animals. Therefore, such waters need to be treated before their use in dairy operations to mitigate risks to dairy cow health and milk safety. To understand the molecular ecology of , this study aimed to assess antimicrobial resistance (AMR) in recovered from untreated surface water sources of dairy farms. Untreated surface water samples ( = 240) from 15 dairy farms were collected and processed to isolate . A total of 234 isolates were obtained and further characterized for their serotypes and antimicrobial susceptibility. Of the 234 isolates, 71.4% were pan-susceptible, 23.5% were resistant to one or two antimicrobial classes, and 5.1% were resistant to three or more antimicrobial classes. Whole genome sequence analysis of 11 selected multidrug-resistant isolates revealed AMR genes including and that confer resistance to the critically important extended-spectrum cephalosporins, as well as a variety of plasmids (mainly of the replicon type) and class 1 integrons. Phylogenetic and comparative genome analysis revealed a genetic relationship between some of the sequenced and Shiga toxin-producing O157:H7 (STEC), which warrants further investigation. This study shows that untreated surface water sources contain antimicrobial-resistant which may serve as a reservoir of AMR that could be disseminated through horizontal gene transfer. This is another reason why effective water treatment before usage should be routinely done on dairy farm operations.

The species of total coliform bacteria isolated from drinking water and untreated surface water by the membrane filter (MF), the standard most-probable-number (S-MPN), and modified most-probable-number (M-MPN) techniques were compared. Each coliform detection technique selected for a different profile of coliform species from both types of water samples. The MF technique indicated that Citrobacter freundii was the most common coliform species in water samples. However, the fermentation tube techniques displayed selectivity towards the isolation of Escherichia coli and Klebsiella. The M-MPN technique selected for more C. freundii and Enterobacter spp. from untreated surface water samples and for more Enterobacter and Klebsiella spp. from drinking water samples than did the S-MPN technique. The lack of agreement between the number of coliforms detected in a water sample by the S-MPN, M-MPN, and MF techniques was a result of the selection for different coliform species by the various techniques.

Surveillance for Waterborne Disease Outbreaks Associated With Drinking Water - United States, 2011-2012.

Reuse of alternative water sources for irrigation (e.g.,untreatedsurface water) is a sustainable approach that has the potential toreduce water gaps, while increasing food production. However, whengrowing fresh produce, this practice increases the risk of bacterialcontamination. Thus, rapid and accurate identification of pathogenicorganisms such as Shiga-toxin producing Escherichiacoli (STEC) is crucial for resource management whenusing alternative water(s). Although many biosensors exist for monitoringpathogens in food systems, there is an urgent need for data analysismethodologies that can be applied to accurately predict bacteria concentrationsin complex matrices such as untreated surface water. In this work,we applied an impedimetric electrochemical aptasensor based on goldinterdigitated electrodes for measuring E. coliO157:H7 in surface water for hydroponic lettuceirrigation. We developed a statistical machine-learning (SML) frameworkfor assessing different existing SML methods to predict the E. coliO157:H7 concentration. Inthis study, three classes of statistical models were evaluated foroptimizing prediction accuracy. The SML framework developed here facilitatesselection of the most appropriate analytical approach for a givenapplication. In the case of E. coliO157:H7 prediction in untreated surface water,selection of the optimum SML technique led to a reduction of testset RMSE by at least 20% when compared with the classic analyticaltechnique. The statistical framework and code (open source) includea portfolio of SML models, an approach which can be used by otherresearchers using electrochemical biosensors to measure pathogensin hydroponic irrigation water for rapid decision support.

Access to safe and clean water is a major challenge in many rural communities of Abia State, Nigeria. Due to the absence of adequate water treatment facilities, residents in these areas depend largely on untreated surface water from rivers, streams, and ponds for domestic, agricultural, and sometimes industrial purposes. This study investigates the environmental effects of untreated surface water in selected rural areas of Abia State, with emphasis on its physical, chemical, and microbiological qualities, and their implications for public health and the ecosystem. Field sampling and laboratory analyses were conducted on multiple surface water sources in rural communities. The results reveal that these waters contain significant levels of turbidity, suspended solids, and colouration exceeding World Health Organization (WHO) permissible limits. Chemical analyses indicated the presence of undesirable mineral concentrations, including high nitrate and phosphate levels from agricultural runoff, and traces of heavy metals such as lead and cadmium. Microbiological tests confirmed the presence of Escherichia coli, total coliforms, and other pathogenic organisms, indicating faecal contamination. These findings suggest that the continued use of untreated surface water poses a dual threat: increased risk of waterborne diseases such as cholera and typhoid, and environmental degradation including eutrophication, biodiversity loss, and soil contamination. The study concludes that urgent interventions—including community-level treatment systems, stricter water protection policies, and sustained public health education—are necessary to mitigate the negative impacts and promote sustainable water management in rural Abia State.

Several research studies reported that mycotoxins and other metabolites can be produced by fungi in certain matrices such as food. In recent years, attention has been drawn to the wide occurrence and identification of fungi in drinking water sources. Due to the large demand of water for drinking, watering, or food production purposes, it is imperative that further research is conducted to investigate if mycotoxins may be produced in water matrices. This paper describes the results obtained when a validated analytical method was applied to detect and quantify the presence of mycotoxins as a result of fungi inoculation and growth in untreated surface water. Aflatoxins B1 and B2, fumonisin B3, and ochratoxin A were detected at concentrations up to 35ng/L. These results show that fungi can produce mycotoxins in water matrices in a non-negligible quantity and, as such, attention must be given to the presence of fungi in water.

Verification of membrane filter total coliform colonies was compared in lauryl tryptose broth, and m-LAC broth primary media and brilliant green-lactose-bile broth and EC broth secondary media. Verification in m-LAC broth yielded the greatest number of aerogenic isolates for both untreated surface water and drinking water samples. Verification in brilliant green-lactose-bile broth increased the number of false-negative reactions. At least 90% of the isolates aerogenic in primary verification media and anaerogenic in brilliant green-lactose-bile broth were representative of the coliform genera. The addition of a resuscitation step in the membrane filter technique did not yield greater numbers of verified coliforms per sample. Verification of both typical and atypical colonies in m-LAC broth resulted in a 10-fold increase in coliform numbers from untreated surface water. With drinking water, verification of both colony types resulted in an increase from less than 1 coliform per 100 ml to greater than 1/100 ml. A single-step verification in m-LAC broth is proposed as a more rapid and sensitive coliform verification procedure than the standard technique.

Prevalence of Shiga-toxigenic and atypical enteropathogenic Escherichia coli in untreated surface water and reclaimed water in the Mid-Atlantic U.S

Disinfection by-products (DBPs) arise when natural organic matter in source water reacts with disinfectants used in the water treatment process. Studies have suggested an association between DBPs and birth defects. Neural tube defects (NTDs) in embryos of untreated control mice were first observed in-house in May 2006 and have continued to date. The source of the NTD-inducing agent was previously determined to be a component of drinking water. Tap water samples from a variety of sources were analyzed for trihalomethanes (THMs) to determine if they were causing the malformations. NTDs were observed in CD-1 mice provided with treated and untreated surface water. Occurrence of NTDs varied by water source and treatment regimens. THMs were detected in tap water derived from surface water but not detected in tap water derived from a groundwater source. THMs were absent in untreated river water and laboratory purified waters, yet the percentage of NTDs in untreated river water were similar to the treated water counterpart. These findings indicate that THMs were not the primary cause of NTDs in the mice since the occurrence of NTDs was unrelated to drinking water disinfection.

Ultraviolet absorption properties of suspended particulate matter in untreated surface waters

The photodegradation of cloramphenicol (CAP) in ultrapure water (UW), untreated surface water (USW), and treated effluent from sewage treatment plant (TESTP) in laboratory scale and pilot scale, was evaluated using solar and artificial radiation. The results show, in all cases, that the CAP degradation occurs according to pseudo-first order kinetics, with the apparent degradation rate constants (kapp) following the order UW ≡ USW > TESTP. The kapp and half-life were strongly influenced by the radiation source. Mono- and di-hydroxyl transformation products were identified in UW after 40 min of solar irradiation, while the acute toxicity to Artemia salina increased from 35% to 100%, respectively after 180 and 1440 min of artificial and solar irradiation (94 and 132 kJ L-1), when 99.2 and 97.7% of CAP degradation occurred. The transformation products did not present antimicrobial activity.

To investigate the risk factors for infection with endemic typhoid fever in the Samarkand region of Uzbekistan. Case-control study of culture-confirmed bloodstream infection with Salmonella Typhi. Patients were compared to age-matched community controls. Salmonella Typhi isolates were tested for antimicrobial susceptibility. We enrolled 97 patients and 192 controls. The median age of patients was 19 years. In a conditional regression model, consumption of unboiled surface water outside the home [adjusted odds ratio (aOR)=3.0, 95% confidence interval (CI)=1.1-8.2], use of antimicrobials in the 2 weeks preceding onset of symptoms (aOR=12.2, 95% CI 4.0-37.0), and being a student (aOR=4.0, 95% CI 1.4-11.3) were independently associated with typhoid fever. Routinely washing vegetables (aOR 0.06, 95% CI 0.02-0.2) and dining at a tea-house (aOR 0.4, 95% CI 0.2-1.0) were associated with protection against illness. Salmonella Typhi resistant to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole was identified in 6 (15%) of 41 isolates tested. Endemic typhoid fever in Uzbekistan is transmitted by contaminated water. Recent use of antimicrobials also increased risk of infection. Targeted efforts at improving drinking water quality, especially for students and young adults, are likely to decrease transmission of typhoid fever. Measures to decrease the unnecessary use of antimicrobials would be expected to reduce the risk of typhoid fever and decrease the spread of multiple drug-resistant Salmonella Typhi.

Influence of membrane fouling by (pretreated) surface water on rejection of pharmaceutically active compounds (PhACs) by nanofiltration membranes