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Dalia A Hamza,1 Reham M Abd-Elsalam,2 Sara M Nader,1 Mahmoud Elhariri,3 Rehab Elhelw,3 Heba S El-Mahallawy4 1Department of Zoonoses, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt; 2Department of Pathology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt; 3Department of Microbiology, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt; 4Department of Animal Hygiene, Zoonoses and Animal Behaviour and Management, Faculty of Veterinary Medicine, Suez Canal University, Ismailia, EgyptCorrespondence: Dalia A HamzaDepartment of Zoonoses, Faculty of Veterinary Medicine, Cairo University, Giza 12211, EgyptTel +20 1 009701262Fax +20 2 35725240Email daliahamza@cu.edu.egBackground: Staphylococcus aureus is considered one of the major threats regarding food safety worldwide. Methicillin-resistant S. aureus (MRSA) strains in livestock, companion animals, and wild animals continue to be a potential risk to people working with them.Aim: The current research aims to investigate the potential pathways of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) strains in the body after oral infection using the experimental mouse model.Methods: Seven groups of SPF male mice were purchased and housed. On day 1, six groups of mice were infected orally by the sterile gastric probe using 100 μL/mice of LA-MRSA bacterial suspension (1 × 108 colony-forming units (CFU)/mL). The remaining group was kept as negative controls. Over 15 days, these animals have been monitored. Fresh fecal samples were screened for LA-MRSA at day 0, day 7 and day 14 following oral administration of MRSA strains. All animals were sacrificed at day 15, and internal organs (liver, lung, kidney, and intestine) were harvested aseptically and divided into two sections. The first part was histopathologically investigated, while the other half has been tested for LA-MRSA re-isolation.Result: The oral challenge of mice by MRSA strains showed that MRSA was re-isolated from feces and intestines of all inoculated mice groups and from internal organs (liver, lung, kidney and intestine) of most mice. Results were confirmed by the detection of the bacteria in gram-stained tissue sections and changes in H&E-stained histopathological tissue sections from these organs.Conclusion: Data from the present study indicate the possible colonization of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) in internal organs following oral infection and thus posing a risk for food-borne infection of MRSA. Infected animals could pass LA-MRSA through feces again, resulting in increased dispersion and environmental contamination.Keywords: Staphylococcus aureus, MRSA, animal model, mice, oral challenge, PCR, histopathology

Methicillin-resistant Staphylococcus aureus (MRSA) is a major challenge for food safety and public health. This study aimed to investigate the potential role of oysters sold in Egypt as a source for Staphylococcus aureus (S. aureus), MRSA, and multidrug-resistant methicillin-resistant Staphylococcus aureus (MDR-MRSA). It also examined the occurrence of tsst-1 virulence gene and assessed the associated zoonotic risks. Thirty-three pooled fresh oyster samples were acquired from different retail fish markets in Egypt. S. aureus was identified by conventional culture-based and molecular methods. Antimicrobial resistance was performed by the disk-diffusion method, and the multiple antibiotic resistance index (MARI) was calculated. Antimicrobial resistance (mecA and mecC) and virulence (tsst-1) genes were screened using polymerase chain reaction. The clustering of virulent MDR-MRSA isolates was performed using R with the pheatmap package. The prevalence of S. aureus was 39.4% (13 /33), and 77% of them (10/13) were classified as MDR with MARI values greater than 0.2. Notably, 46.2% (6 /13) of isolates were identified as MRSA and all MRSA isolates displayed MDR. Of the MDR-MRSA isolates, 66.7% (4 /6) possessed the mecA gene, while 16.7% (1 /6) tested positive for the mecC gene. Additionally, the tsst-1 gene was identified in one isolate (16.7%). Interestingly, two MDR-MRSA isolates exhibited a clustered pattern. The study sheds light on the emergence of virulent MDR-MRSA isolates in Egyptian oysters. It highlights oysters as a potential source for spreading these isolates within aquatic ecosystems, posing a threat to food safety and public health., Competing Interests: Declarations. Competing interests: The authors declare no competing interests. Consent for publication: All authors have read the manuscript and consent to publish., (© 2025. The Author(s).)

The emergence of critical-priority E. coli, carrying a wide array of resistance and virulence factors through food sources, poses a significant challenge to public health. This study aimed to investigate the potential role of oysters sold in Egypt as a source for E. coli, identify their resistance and virulence-associated gene profiles, and assess associated zoonotic risks. A total of 33 pooled fresh oyster samples were obtained from various retail fish markets in Egypt and examined bacteriologically for the presence of E. coli. Antimicrobial resistance was performed by the disk-diffusion method, and the multiple antibiotic resistance index (MAR) was calculated. All isolates were screened for extended-spectrum beta-lactamase (ESBL) (bla TEM , bla SHV , bla CTX-M, and bla OXA-1 ), plasmid-mediated AmpC bla CMY-2 , and carbapenemases (bla KPC , bla NDM , bla VIM , and bla OXA-48 ) genes by Polymerase chain reaction. Moreover, the presence of virulence-encoding genes was investigated. The virulent MDR strains were clustered using R with the pheatmap package. The prevalence of E. coli was 72.7% (24 out of 33), with 66.7% of the isolates classified as multi-drug resistant, and 75% exhibited MAR values exceeding the 0.2 threshold. Different antimicrobial sensitivity phenotypes and genotype profiles were identified in E. coli isolates. The most prevalent gene detected among all isolates was bla TEM (22/24, 91.7%). Notably, all non-ESBL producers were positive for bla CMY2 . Carbapenem-resistant and carbapenem-intermediate strains were carbapenemase producers, with the predominance of the bla KPC gene (11/24, 45.8%). Remarkably, twelve out of sixteen virulence genes were identified, with papC (21/24, 87.5%) and sfa (16/24, 66.7%) genes being the most prevalent. Most isolates carry virulence genes primarily associated with extra-intestinal pathogenic E. coli (ExPEC) (87.5%) and enteropathogenic (EPEC) (70.8%) pathotypes. Four E. coli isolates exhibit cluster patterns. This study provides the first insight into the emergence of virulent MDR E. coli among oysters in Egypt. It underscores the potential role of oysters as a source for disseminating these strains within aquatic ecosystems, presenting a possible threat to public health., (© 2024. The Author(s).)

Background: The global dissemination of critical-priority carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKp) via food sources represents a significant public health concern. Epidemiological data on CR-hvKp in oysters in Egypt is limited. This study aimed to investigate the potential role of oysters sold in Egypt as a source for carbapenem-resistant K. pneumoniae (CRKP), hypervirulent K. pneumoniae (hvKp), and CR-hvKp and assess associated zoonotic risks., Methods: A sample of 330 fresh oysters was randomly purchased from various retail fish markets in Egypt and divided into 33 pools. Bacteriological examination and the identification of Klebsiella pneumoniae were performed. Carbapenem resistance in K. pneumoniae isolates was determined by phenotypic and molecular methods. Additionally, the presence of hypervirulent K. pneumoniae was identified based on virulence gene markers (peg-344, rmpA, rmpA2, iucA, and iroB), followed by a string test. The clustering of CR-hvKp strains was carried out using R with the pheatmap package., Results: The overall prevalence of K. pneumoniae was 48.5% (16 out of 33), with 13 isolates displaying carbapenem resistance, one intermediate resistance, and two sensitive. Both carbapenem-resistant K. pneumoniae and carbapenem-intermediate-resistant K. pneumoniae strains exhibited carbapenemase production, predominantly linked to the bla VIM gene (68.8%). HvKp strains were identified at a rate of 62.5% (10/16); notably, peg-344 was the most prevalent gene. Significantly, 10 of the 13 CRKP isolates possessed hypervirulence genes, contributing to the emergence of CR-hvKp. Moreover, cluster analysis revealed the clustering of two CR-hvKp isolates from the same retail fish market., Conclusion: This study provides the first insight into the emergence of CR-hvKp among oysters in Egypt. It underscores the potential role of oysters as a source for disseminating CR-hvKp within aquatic ecosystems, presenting a possible threat to public health., (© 2024. The Author(s).)

Objective: The study was designed to show the effect of adding different levels of dried fruit extracts for 14 days on sensory and chemical parameters in dairy drinks. The survival of Pseudomonas aeruginosa and Bacillus cereus in artificially contaminated dairy drinks fortified with these extracts was also studied., Materials and Methods: The freshly watery extracts and nonaqueous extracts of dried fruits were prepared by rotary evaporators and solvents, respectively. The determination of the minimum inhibitory concentration of dried fruit extracts was achieved using the disc diffusion test. The sensory evaluation of samples was done, while the chemical parameters of the examined samples were determined by the calibrated analyzer. In addition, the degree of survival of P. aeruginosa and B. cereus in inoculated milk samples was also estimated., Results: In pasteurized and Rayeb milk samples, the water extract of carob and all alcoholic dried fruit extracts had a significant effect on compositional parameters in comparison to control samples. At day 14 of pasteurized milk storage, the watery (20.0%) and alcoholic (10.0%) extracts of carob significantly improved its sensory parameters., Conclusion: Based on the survival results, all utilized dried fruit extracts had a significant inhibitory effect on P. aeruginosa and B. cereus growth in the fortified milk samples at the end of storage. This trial of the survival of these new dairy drinks is the first investigation, particularly in the Middle East. Extracts of utilized dried fruits have prospective functions that enhance dairy drink characteristics., Competing Interests: The authors declare no conflicts of interest., (Copyright: © Journal of Advanced Veterinary and Animal Research.)

Introduction Veterinarians and other professionals who interact with animals on a daily basis encounter an elevated risk of exposure to both known and as-yet-undiscovered microbial agents. Additionally, they are also exposed to physical, chemical, and environmental hazards. Enhancing occupational health and safety in this context carries significant global significance. Methods This study aimed to comprehensively identify and outline the various biological, physical, chemical, and environmental health threats that were encountered by veterinarians in Saudi Arabia. To achieve this, we designed a self-completed questionnaire for 529 participants. The survey encompassed potential occupational hazards such as microbial diseases, injuries resulting from animal bites and scratches, allergies, and environmental risks like sunstroke and dust storms. Results Among the 529 participating veterinarians, 45.9% (243 individuals) reported instances of zoonotic diseases within the past five years. Notably, potential viral agents included Middle East respiratory syndrome coronavirus, avian influenza, and foot-and-mouth disease virus. Bacterial diseases were also frequently documented, with brucellosis (18.7%) and salmonellosis (7.9%) being notable pathogens. Protozoal infections were led by Leishmaniosis, constituting the most commonly detected protozoa (29 /529, 5.5%). Interestingly, 345 (65.2%) of the individuals reported that they have experienced animal bites and scratches. Needle stick injuries were also a common occupational hazard, with an incidence rate of 19.1%. Additionally, chemical exposure was prevalent, particularly to disinfectants (57.5%) and veterinary drugs (23.4%). The study participants also reported their exposure to various environmental hazards, including sunstroke, dust, sandstorms, and heavy rains. Conclusion The findings of this study draw attention to a concerning trend among veterinarians in Saudi Arabia. Their personal health and safety appear to receive inadequate attention, potentially heightening the risk of occupationally related health hazards. These outcomes highlight the need for a reevaluation of safety protocols and infection control practices within the veterinary profession. The implications of this study can potentially inform the development of policies and initiatives aimed at mitigating occupationally related health hazards among veterinarians in Saudi Arabia., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Al-Harbi et al.)

Pseudomonas aeruginosa (P. aeruginosa) is a serious zoonotic pathogen threaten the poultry industry causing severe economic losses therefor, this study aimed to isolation, phenotypic, molecular identification of P. aeruginosa from different avian sources (chickens, turkey, pigeons, table eggs, and dead in shell chicken embryos), from different Egyptian governorates (Giza, Qalubia, Beheira, El-Minya, and Al-Sharqia) with applying of antibiotic sensitivity test on all P. aeruginosa isolates. Highly resistant isolates (n = 49) were subjected to molecular identification of P. aeruginosa with detection of resistant genes including carbapenemase-encoding genes blaKPC, blaOXA-48, and blaNDM. On the base of molecular results, a highly resistant P. aeruginosa strain was tested for its pathogenicity on day old specific pathogen free (SPF) chicks. Also, in vitro experiment was adopted to evaluate the efficacy of silver nanoparticles (Ag-NPs) against highly antibiotic-resistant P. aeruginosa strains. The overall isolation percentage was from all examined samples were 36.2% (571/1,576) representing 45.2% (532/1,176) from different birds' tissues and 39/400 (9.7%) from total egg samples. Some of isolated strains showed multidrug resistance (MDR) against kanamycin, amoxicillin, amoxicillin-clavulanic acid, neomycin, chloramphenicol, vancomycin, cefotaxime clavulanic acid, lincomycin-spectinomycin, co-trimoxazole, cefoxitin, gentamycin, and doxycycline. These MDR strains were also molecularly positive for ESBL and carbapenemase-encoding genes. MDR strain showed high pathogenicity with histopathological alterations in different organs in challenged birds. Main histopathological lesions were necrosis of hepatocytes, renal tubular epithelium, and heart muscle bundles. The MDR strain showed in vitro sensitivity to Ag-NPs. In conclusion, MDR P. aeruginosa is a serious pathogen causing high morbidity, mortality, and pathological tissue alterations. Ag NPs revealed a promising in vitro antimicrobial sensitivity against MDR P. aeruginosa and further in vivo studies were recommended., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background and Aims: Increasing lesion size is a risk factor for recurrence after piecemeal EMR (pEMR). Snare-tip soft coagulation (STSC) treatment of the normal-appearing margin after pEMR of lesions ≥ 20 mm has been shown to reduce recurrence rates by 75% to 80%. We sought to evaluate the impact of STSC on giant (≥ 40 mm) lateral spreading lesions treated by pEMR. We describe the relative risk and absolute risks of recurrence with and without STSC margin treatment after EMR of ≥ 40-mm lesions., Methods: We performed a retrospective evaluation of a prospectively collected database on large lesions describing lesion size, location, and methods of resection. We excluded lesions < 40 mm in maximum dimension, those that did not undergo follow-up care at our center, and those in which argon plasma coagulation was used for either ablative treatment of residual polyp or margin treatment. Propensity score analysis was used to account for potential differences between patients treated with and without STSC., Results: There were 68 lesions ≥ 40 mm removed by pEMR without STSC treatment and 133 removed and treated with STSC. There were no differences between groups in demographics, polyp size, location, histologic features, and mean follow-up time. The recurrence rate in the no-treatment group was 35% versus 9% with STSC (P < .00001 by direct comparison and P = .008 by using the propensity score analysis)., Conclusion: STSC treatment after pEMR of large lateral spreading lesions in the colorectum reduced recurrences by 75%. However, the absolute recurrence rate of 9% remained clinically significant in the STSC-treated group. Short-term follow-up care after STSC of lesions ≥ 40 mm is still warranted, and additional study of technical factors that eliminate recurrence after pEMR of giant lateral spreading lesions is warranted., (Copyright © 2023 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.)

Background and Aim: Fresh produce farms represents a major source of concern since they are becoming increasingly antibiotic resistant. This study aimed to investigate the occurrence of carbapenemase and extended-spectrum-beta-lactamases (ESBL) - producing genes in Klebsiella pneumonia e isolated from fresh produce farms in Egypt, irrigation water, and people working in these fields., Materials and Methods: One hundred tomatoes from typical farms were collected in plastic bags. The study also included 20 surface-water samples from different irrigation watersheds in fresh produce farms, as well as 50 feces samples from farmworkers. Suspected K. pneumoniae was grown on Eosin Methylene Blue agar for 24 h before being biochemically identified using the RapID ONE test. PCR was used to detect carbapenemase ( bla KPC, bla OXA-48, and bla NDM) and ESBL ( bla SHV, bla TEM, and bla CTX) expressing genes on isolates., Results: K . pneumoniae was identified in 30% of water and 10% of worker samples, while only one isolate was found in tomato samples. One of the six irrigation water isolates tested positive for carbapenem-resistant NDM. In contrast, two isolates tested positive for ESBL determinants, one of which was bl SHV and the other having both bla SHV and bla TEM genes. Two of the five K. pneumoniae isolates from farmworkers were positive for bla NDM, with one isolate also testing positive for bla SHV and bla TEM. The bla OXA-48 gene was also discovered in the carbapenem-resistant K. pneumoniae tomato isolate used in this study., Conclusion: Carbapenemase- and ESBL-producing K. pneumoniae were found in fresh produce farms, implying that these resistance genes were being passed down to Egyptian consumers., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Elshafiee, et al.)

Background: Cryptococcosis is an opportunistic mycozoonosis of global significance in a wide variety of host species. In equines, cryptococcosis is uncommon, and sporadic cases have been reported with rhinitis, sinusitis, pneumonia, and meningitis. Cryptococcus spp. represents a potential risk for immunosuppressed and healthy persons. In Egypt, epidemiological data on cryptococcal infection in horses are limited. The current study was carried out to investigate the occurrence of Cryptococcus spp. in horses and its possible role in the epidemiology of such disease in Egypt. A total of 223 samples was collected from different localities in Egypt included 183 nasal swabs from horses, 28 nasal swabs from humans, and 12 soil samples. Bacteriological examination and the identification of Cryptococcus spp. were performed. Molecular serotyping of Cryptococcus spp. was determined by multiplex PCR using CNa-70S/A-CNb-49S/A. The virulence genes (LAC1, CAP59, and PLB1) of the identified isolates were detected by PCR. Moreover, sequencing and phylogenetic analysis of the C. gattii gene from horses, humans, and soil isolates found nearby were performed., Result: The overall occurrence of Cryptococcus spp. in horses were 9.3, 25, and 10.7% in horses, the soil, and humans, respectively. Molecular serotyping of the Cryptococcus spp. isolates recovered from the nasal passages of horses proved that C. gattii (B), C. neoformans, and two hybrids between C. neoformans (A) and C. gattii (B) were identified. Meanwhile, in case of soil samples, the isolates were identified as C. gattii (B). The human isolates were serotyped as C. gattii in two isolates and C. neoformans in only one isolate. Molecular detection of some virulence genes (LAC1), (CAP59), and (PLB1) were identified in both C. gattii and C. neoformans isolates. The C. gattii gene amplicons of the isolates from horses, humans, and the soil were closely related., Conclusion: This study provides the first insights into the Egyptian horse ecology of Cryptococcus species and highlights the role of horses as asymptomatic carriers in disseminating the potentially pathogenic Cryptococcus spp. It also presents the possible risk of cryptococcosis infection in humans., (© 2022. The Author(s).)

Toxocara canis of dogs and Toxocara vitulorum of cattle and buffalo are nematode parasites that cause serious economic and public health problems all over the world. This study aims to provide molecular data to identify and distinguish between Toxocara spp. from dogs, cattle and buffalo in Egypt. Moreover, constructing a phylogeny and phylogenetic relationships among these Toxocara spp. were performed through an analytic study of ATPase-6, a mitochondrial gene; 12S, small subunit ribosomal RNA gene and ITS-2, the second internal transcribed spacer nuclear ribosomal gene. T. vitulorum from cattle and buffalo were found to be almost identical. The ATPase- 6 and 12S regions showed 87.78 % and 90.38 % nucleotide similarity between T. canis and T. vitulorum , while for the ITS-2 region, only 78.38 % was found. Analysis of the three studied genes revealed that each Toxocara spp. has distinct molecular characteristics. Moreover, it was revealed that these genes, especially the ITS-2 gene, are useful and sensitive molecular markers for classifying and studying the phylogenetic analysis and relationships among closely related Toxocara spp. All sequences obtained in this study were registered in the GenBank under the accession numbers: MG214149 -MG214157., Competing Interests: Conflict of Interest The authors have declared no conflict of interest, (© 2020 O. A. Mahdy, W. M. Mousa, S. Z. Abdel-Maogood, S. M. Nader, S. Abdel-Radi, published by Sciendo.)

Introduction: Carbapenem-resistant Pseudomonas aeruginosa (CRPA) has become the leading cause of health care-associated infections. Treatment is difficult due to the lack of an effective antimicrobial therapy, and mortality is high. This study investigated the occurrence of CRPA in farm animals (buffaloes and cattle), livestock drinking water, and humans in Egypt., Material and Methods: A total of 180 samples were examined: 50 faecal each from buffaloes and cattle, 30 of livestock drinking water, and 50 stool from humans. The samples were cultured on cetrimide agar and the plates were incubated aerobically at 37°C for 24 h. The isolates were examined for the presence of the bla KPC , bla OXA-48 , and bla NDM carbapenemase-encoding genes using PCR and investigated for the exotoxin A ( toxA ) gene. The toxA gene from carbapenem- group resistant isolates was phylogenetically analysed., Results: P. aeruginosa was isolated from buffaloes, cattle, drinking water, and humans, with occurrences of 40%, 34%, 10%, and 20%, respectively. Carbapenem resistance genes were found in 60%, 59%, 67%, and 70% in buffalo, cattle, water and human samples, respectively. The toxA gene was detected in 80% of samples. The phylogenetic analysis showed that cattle and water sequences were in one cluster and more related to each other than to human isolates., Conclusion: Occurrence of CRPA among farm animals, drinking water, and humans was high, reflecting the environmental origin of P. aeruginosa and highlighting contaminated water as a potential transmitter of CRPA to livestock and next to humans., Competing Interests: Conflict of Interest Conflict of Interests Statement: The authors declare that there is no conflict of interests regarding the publication of this article., (© 2019 E.A. Elshafiee et al. published by Sciendo.)

Cryptosporidium parvum is a highly prevalent zoonotic and anthroponotic protozoan parasite that causes a diarrheal syndrome in children and neonatal livestock, culminating in growth retardation and mortalities. Despite the high prevalence of C. parvum, there are no fully effective and safe drugs for treating infections, and there is no vaccine. We have previously reported that the bacterial-like C. parvum lactate dehydrogenase (CpLDH) enzyme is essential for survival, virulence and growth of C. parvum in vitro and in vivo. In the present study, we screened compound libraries and identified inhibitors against the enzymatic activity of recombinant CpLDH protein in vitro. We tested the inhibitors for anti-Cryptosporidium effect using in vitro infection assays of HCT-8 cells monolayers and identified compounds NSC158011 and NSC10447 that inhibited the proliferation of intracellular C. parvum in vitro, with IC50 values of 14.88 and 72.65 μM, respectively. At doses tolerable in mice, we found that both NSC158011 and NSC10447 consistently significantly reduced the shedding of C. parvum oocysts in infected immunocompromised mice's feces, and prevented intestinal villous atrophy as well as mucosal erosion due to C. parvum. Together, our findings have unveiled promising anti-Cryptosporidium drug candidates that can be explored further for the development of the much needed novel therapeutic agents against C. parvum infections., Competing Interests: The authors have declared that no competing interests exist.

Background and Aim: Salmonellosis is one of the most common foodborne bacterial diseases in the world. The great majority of Salmonella infections in humans are foodborne with Salmonella enterica and Salmonella Typhimurium accounting for a major part of the problem. The objective of this study was to investigate the presence of invA gene in strains of Salmonellae isolated from eggs and diarrheal swabs from human cases. In addition, the relationship between inv A gene nucleotide sequences from different sources (human stool and egg samples) have been studied through phylogenetic tree., Materials and Methods: One hundred and seventy eggs (eggshell and its contents) and 160 stool swabs samples were collected from four poultry farms and medical hospital in Giza Governorate., Results: The study reported the presence of two Salmonella strains in eggshell surface with an overall isolation rate of 1.2 and 0% of the egg content. Salmonella Enteritidis and Salmonella Typhimurium were isolated from eggshell surface with an incidence of 50% for each strain. Six salmonella strains were isolated from human stool with an incidence of 3.75%; the isolated strains are S . Typhimurium, S . Enteritidis, Salmonella Virchow, Salmonella Haifa, and Salmonella Kentucky with an incidence of 33.3%, 16.6%, 16.6%, 16.6%, and 16.6%, respectively. Among eight Salmonella strains, invA gene was detected with percentage of 50%. The phylogenetic analysis of the sequences invA gene, from two isolates included in this study and five isolates retrieved from GenBank showed that sequence from human, layer hens, egg, and water in the same clusters., Conclusion: Close relation between drinking contaminated water and layer hens and contaminated water is one such source.