English

This research was developed in the sub-basin of the Puyo River, Province of Pastaza, Ecuador, in the years 2015 and 2018 had as objective: To characterize the environmental quality of water, in different sectors of the sub-basin of the Puyo River, including the main tributaries. The zones were classified as high, urban and low. A monitoring was carried out in the main channel and its tributaries in 28 points, registering values ​​of conductivity, pH, temperature and oxygen saturation, chemical oxygen demand, biochemical oxygen demand, total and fecal coliforms, and 413 surveys were applied to identify the Main types of activities that take place in the areas surrounding the main course and tributaries. The results showed differences in the concentrations of the different parameters in the dates and monitoring points, reporting higher concentrations of BOD5, total and fecal coliforms, the areas of the urban area. The correlation analysis showed significant relationships between the variables studied except for oxygen saturation. The analysis of variance showed significant differences between the zones for electrical conductivity, concentration of fecal and total coliforms. Surveys reveal that the majority of wastewater is deposited directly into the sewer system and the main channel of the river. It is concluded that the behavior of the different registered variables differs between the main body and tributaries, increasing the concentrations of total Coliforms, fecal from the urban area in the main body and differing the behavior of the rest of the parameters in the three zones.

Bacteriological analyses of 3,942 water samples was undertaken. Samples hailed from many different sources, or rather, reservoirs (1,033), faucets (1,594), swimming pools (789), spring water (96), private wells (350) and others (80). They were obtained for routine testing between 1996 and 1999 and comparatively analyzed for total and fecal coliform bacteria by a multiple-tube fermentation technique. Total and fecal coliform bacteria were detected in 595 and 235 of the water samples, respectively, and were associated with the following factors: as raw water, chlorinated water, source water, wet season, dry season, pH, and disinfectant residuals. As expected, the highest number of water samples contaminated by total (362) and fecal (159) coliform bacteria was found in the raw water at source and at the consumption end among urban and rural communities. The people of these areas use water directly from available sources, without any treatment and are therefore exposed to a variety of water-related diseases.

Water quality and socio-economic status of beach communities was studied in the Thruston Bay catchments of Lake Victoria. The major aim of the study was to establish the relation between water quality and socio-economic status of the communities in the study sites and come up with a sustainable community-designed system to control water quality degradation. Physico-chemical characteristics of water were determined on-site while total and fecal coliforms were determined in the laboratory using standard methods. The most probable number (MPN) technique was used to determine the total coliforms (TC) while the fecal coliform (FC) Test was used for testing the presence or absence of fecal coliforms. All sites tested positive for total and fecal coliforms. Borehole water had the highest MPN values followed by 10 m site. To compliment on the water quality data collected, a socio-economic status study of beach communities was conducted using questionnaires, structured interviews, focus group discussions and observations. Data and information on the demographic characteristics, asset ownership, livelihood activities, social facilities, health and sanitation, communication and outreach, solid waste and fisheries management and Beach Management Units (BMU) establishments, among others, was collected. A method in form of a model was designed using a participatory approach by the beach communities to be used to ameliorate lakeshore degradation by the communities in collaboration with other stakeholders.

The preservation of hydric resources is directly related to fecal contamination monitoring, in order to allow the development of strategies for the management of polluting sources. In the present study, twenty-five water samples from six water public supply collection sites were used for the evaluation of the presence of caffeine, total and fecal coliforms. Caffeine was detected in all samples, with concentrations ranging from 0.15 ng mL-1 to 16.72 ng mL-1. Total coliforms were detected in all samples, with concentrations in the range of 52 NMP/100 mL to higher than 24196 NMP/100 mL, whether the concentration range for fecal coliforms was in the range of below 1 NMP/100 mL to 7800 NMP/100 mL. No significant correlation was found between total coliforms and caffeine concentrations (rs = 0.35, p = 0.09). However, a moderate correlation between fecal coliforms and caffeine concentrations was found (rs = 0.412, p <0.05), probably indicating a human source for these bacteria. Caffeine determination in water may be a useful strategy to evaluate water contamination by human fecal waste.

A collaborative study was conducted in 18 laboratories to assess the performance of the hydrophobic grid membrane filter method against that of the AOAC official first action method 46.013-46.016 for enumerating total and fecal coliforms and Escherichia coli. The study was carried out on frozen breaded fish, raw comminuted poultry, unroasted walnut pieces, ground black pepper, and cheddar cheese. The hydrophobic grid membrane filter method recovered significantly larger numbers of target bacteria in 7 of the food/analysis combinations: fecal coliforms in fish; E. coli in poultry; fecal coliforms and E. coli in walnuts; and total coliforms, fecal coliforms and E. coli in black pepper. Random error (Sr2) associated with the hydrophobic grid membrane filter method was significantly lower than that of the reference method in over 30% of the paired sample series. The hydrophobic grid membrane filter method for total coliform, fecal coliform, and E. coli enumeration in foods has been adopted official first action.

Monitoring microbial safety and evaluation of removal efficiency from drinking water in Ahvaz, Iran

Purpose In waters and wastes, direct pathogen detection is difficult and time consuming. Therefore, coliforms are used as indicators to measure the presence of pathogens. Composts originated from extrements, sewage sludges and plant wastes those contact with manures may have potential health hazard to human. Therefore, the detection of coliforms both during composting and in the obtained composts is used to investigate the presence of pathogens for determination of the potential health risk. Methods In this study, the effect of six different aeration rates on elimination of total and faecal coliform bacteria was investigated during in-vessel aerobic composting of vegetableâfruit wastes. Total coliform and faecal coliform numbers in the samples were measured by the most probable number method. Results Coliforms significantly increased before the thermophilic stage except the faecal coliforms in the reactor which operated with the lowest aeration. The coliforms suddenly decreased after thermophilic stage in all reactors. Total coliforms reduced within the range of 78.2â99.9 % while faecal coliforms reduced within the range of 72.5â99.9 % after the thermophilic stage. At the end of the composting period (day 18), total coliforms and faecal coliforms reduced within the range of 99.9â100 %. Conclusions Although all the aeration rates used in the present study were effective for the elimination of coliforms, the lowest faecal coliform number was seen in the reactor that had the lowest aeration rate. At the end of the study, the faecal coliform numbers in all reactors confirmed some limits for the application activities of composts.

Movement of faecal indicator organisms in earthworm channels under a loamy arable and grassland soil

Treated effluent discharge can significantly alter river water quality by affecting parameters such as pH, turbidity, conductivity, and coliform levels, thereby posing risks to both ecosystems and human health. This study evaluated the impact of effluent discharge from the Wupa Wastewater Treatment Plant Abuja, Nigeria on the water quality of the Wupa River. A refined parametric water quality index was developed to enhance monitoring precision, as traditional indices often lack sensitivity to variations in individual parameters. Water samples were collected during the rainy season’s peak mixing period (June–August) from six stations: the influent (INF), effluent (EFF), the point of discharge (POD), upstream of POD (UPOD), and two downstream locations (1kmPOD and 2kmPOD). The samples were analyzed for physical appearance, pH, temperature, conductivity, turbidity, total coliforms, and fecal coliforms. The parametric index incorporated three components: concentration factor, percentage equivalence, and percentage change, to capture parameter-specific changes. Results revealed distinct spatial variations in water quality across the stations. The INF had poor quality, with turbidity between 203–209NTU, total coliforms up to 6000/100 mL, and fecal coliforms also reaching 6000/100 mL, along with a darkish appearance. The EFF showed improvement, with turbidity reduced to 16–19NTU and total coliforms to 400–2000/100 mL, indicating partial treatment success. The UPOD station showed moderate pollution, with turbidity between 69–94 NTU, total coliforms at 600–3000/100 mL, and fecal coliforms ranging from 880–1600/100 mL. At the POD, contamination intensified: turbidity rose to 84–95 NTU, total coliforms increased to 1750–4500/100 mL, and fecal coliforms to 400–900/100 mL. Further downstream, values remained high—turbidity (80–85 NTU), total coliforms (650–3000/100 mL), and fecal coliforms (700–1220/100 mL). pH remained nearly neutral (6.91–7.65), and temperature ranged from 23.8–28.3 °C. Statistical analysis (ANOVA and t-tests) showed significant differences (p < 0.05) in conductivity (245–345 µS/cm), turbidity, and all coliform counts across stations, while differences in pH and temperature were not significant. The parametric index further revealed that treated effluent influenced river quality through elevated turbidity, minor pH variations (+2% in June, −2% to −4% in July and August), and significant increases in coliform levels. Temperature at the POD rose by 5%–12% but declined downstream. Conductivity increased at the POD(+15.5% to +23%) and remained elevated downstream. Turbidity also increased at the POD(+21.7% in June) before declining. Total coliforms surged at the POD(+50% to +191.7%), with residual contamination downstream, while fecal coliforms showed mixed patterns. These findings indicate that although some parameters return to near-background levels within 1 km, microbial contamination persists, raising concerns about waterborne diseases and the safety of downstream water use. The study concludes that the parametric water quality index is effective in assessing site-specific impacts of effluent discharge and underscores the urgent need for improved wastewater treatment and ongoing water quality monitoring to protect public health and environmental integrity.

The present study has been undertaken to evaluate the performance of wastewater treatment systems (WWTS) in three different districts (Kolkata, Howra and Hugli) in West Bengal, India. Performance of these wastewater treatment plants are essential parameter to be monitored as the treated effluent is discharged into River Ganga which is the National River of India. The performance evaluation will also help for the better understanding of design and operating difficulties in wastewater treatment plants. The performance evaluation was done on the basis of removal efficiency of Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), Total Coliform (TC) and Fecal Coliform (FC). The performance of prevailing oxidation pond and activated sludge process type was good in terms of BOD, COD and TSS removal. Even though the removal efficiency of total and fecal coliform was high (85-98%), none of the plants meet the coliform discharge standards because of the high incoming TC and FC.

UV radiation and ozonation were investigated as disinfection alternatives for the wastewater treatment plant. The inactivation of total and fecal coliforms using ozone and ultraviolet radiation as separate treatments was evaluated. Different ozone concentrations (3 to 40 mg O3/L) were applied and UV fluencies ranging from 8.5 to 12 mJ/cm2 at different pH values (from 5 to 9) were tested. Best results were obtained for ozone doses near 20 mg/min with removals of 72% and 78% of fecal and total coliforms, respectively. The ozone also was capable of oxidizing organic matter in the effluent measured as COD (the highest removal obtained was 36% for 20 mg O3/min). Maximum bacterial resistance was observed at pH 7 in both cases. The UV light offered a high bacterial inactivation (over 80%) and the lowest bacterial inactivation was observed at pH 7. Finally, we obtained the electric energy per order (EEO, kWh/m3/order), defined as the electric energy (kW-h) required to degrade a contaminant by one order of magnitude in a unit volume of contaminated water, being noteworthy that EEO values for the UV process resulted were lower than those determined for the process with ozone in all the water flow tested.

This study investigated the bacteriological contamination of different water sources in Sri Lanka. Source waters (n = 74) including bottled water, well water and surface water were assessed for enumerating total coliforms and faecal coliforms using the membrane filtration method. The results showed that 18.5 and 14.8% of bottled water samples were contaminated with total coliforms and faecal coliforms, respectively. All the well water and surface water samples exceeded the WHO permitted levels for total coliforms and faecal coliforms. Bacteriological identification using biochemical tests and api 20E identification tests revealed the presence of potentially pathogenic bacteria in all water sources tested. Bottled water mainly contained three Enterobacter species, while well water samples showed the broadest spectrum of bacteria including eleven coliform species belonging to the genera Klebsiella, Escherichia, Enterobacter, Citrobacter, Kluyvera, Pantoea, Rautella, and 10 non-coliform species in the genera Pseudomonas, Aeromonas, Salmonella and Acinetobacter. Surface waters contained seven coliform species belonging to the genera Klebsiella, Escherichia, Citrobacter, Rautella and Serratia, and eight non-coliform species in the genera Pseudomonas, Aeromonas and Acinetobacter. Detection of higher bacteriological counts and identification of potentially pathogenic bacteria in different source waters suggest a potential health risk of the water sources used in Sri Lanka.

A survey of the microbiological quality of water from 194 boreholes (97 privately owned and 97 communal boreholes) in the rural Thitale-Hlanganani area of the Limpopo Province, South Africa was carried out between August 2002 and August 2003. Very little information on the microbiological quality of privately-owned boreholes in rural communities is available raising concerns about the safety of these groundwater supplies. In this study, levels of total coliforms, thermotolerant (faecal) coliforms, faecal enterococci, Clostridium perfringens (vegetative cells and spores) and somatic coliphages were determined for community and privately-owned borehole water. The average counts for total coliforms, faecal coliforms, faecal enterococci and Clostridium perfringens exceeded the South African recommended guideline limits of 0-10 counts.100 ml(-1) for total coliforms and 0 counts. 100 ml(-1) for faecal coliforms, faecal enterococci and Clostridium perfringens respectively. Comparisons between the levels of indicator bacteria present in private and communal boreholes during dry seasons indicated a statistical difference for faecal enterococci bacteria (p = 0.005) and Clostridium perfringens (p = 0.08). Comparisons between the levels of indicator bacteria present in private and communal boreholes during rainy seasons indicated statistical differences between total coliforms (p = 0.05), faecal coliforms (p = 0.03) and Clostridium perfringens (p = 0.009) bacteria. No significant differences in the presence of somatic coliphages in both private and communal borehole water were see. The results indicated the need for environmental impact assessment studies to monitor the microbiological quality of groundwater sources in rural communities.

Residents of Nepal's Kathmandu Valley draw drinking water from tube wells, dug wells, and stone spouts, all of which have been reported to have serious water quality issues. In this study, we analyzed drinking water samples from 35 tube wells, dug wells, stone spouts, and municipal tap water for bacterial and chemical contaminants, including total and fecal coliform, aluminum, arsenic, barium, beryllium, boron, cadmium, cobalt, chromium, copper, fluoride, iron, mercury, manganese, molybdenum, nickel, lead, antimony, selenium, thallium, uranium, vanadium, and zinc. We also asked a sampling of households who used these specific water sources to rate the taste of their water, list any waterborne diseases they were aware of, and share basic health information about household members. This survey provided us with information from 146 households and 603 individuals. We found widespread bacterial contamination of water sources, with 94% of sources having detectable total or fecal coliform. Nepal Drinking Water Quality Standards and World Health Organization (WHO) Drinking-Water Guidelines or health-based values were exceeded for aluminum (max = 0.53 mg/L), arsenic (max = 0.071 mg/L), iron (max = 7.22 mg/L), and manganese (max = 3.229 mg/L). The distribution of water sources with high arsenic, iron, and manganese appeared to be associated with floodplain deposits. Mixed effects logistic regression models were used to examine the interactions between social factors and water contaminants and their effects on household members' health. Consumers of water sources with both high and low concentrations of manganese were less likely to have a positive attitude towards school than those whose water sources had moderate concentrations of manganese. Social factors, especially education, played a large role in predicting individual health outcomes. Household taste ratings of drinking water were not correlated with iron or manganese concentrations, suggesting that WHO's reliance on aesthetic criteria for these contaminants instead of formal drinking-water guidelines may not be sufficient to protect public health.

The study was conducted to assessment of two drinking water treatment plants in Baghdad City, Iraq from December 2016 to July 2017. Three sites for each plant were selected which represent the sedimentation basin, filtration basin and final stages after chlorination. Seventeen physicochemical parameters of water quality were analyzed in this assessment. These parameters were temperature, turbidity, electrical conductivity, pH, dissolved oxygen, biological demand oxygen, total dissolved solids, total hardness, nitrate, phosphate, calcium, magnesium, residual chlorine and heavy metals (lead, cadmium, Nikel and Chromium). In addition to four bacterial indicators of drinking water pollution (APC, Total Coliform, Fecal Coliform and Salmonella spp). The results showed variation in drinking water quality parameter values in both treatment plants. Moreover, the presence of numbers of bacteria greater than permissible limit, indicating a deficiency in the purification process.