Bacteriological quality of household drinking water in North Gondar Zone, Ethiopia; a community-based cross-sectional study

Ethiopia is one of the developing countries where only 52% of its population have access to safe drinking water. To determine the level of faecal contamination in drinking water, the E. coli has been found to be the most specific indicator. The purpose of this study was to determine household bacteriological drinking water quality and its associated factors in rural North Gondar Zone Ethiopia. A community-based cross-sectional study was conducted in rural parts of North Gondar Zone from April to June, 2016. Water samples from water storage at household level were taken using standardized water sampling techniques to determine the level of faecal contamination. Face-to-face interview using structured questionnaires and checklist were used to identify the associated factors. A total of 736 households participated in this study. The prevalence of positive faecal coliform in the households is found to be 72.6% (95%C.I; 69.4–75.8). In multivariate analysis; occupational status [AOR; 0.35, 95%; CI (0.16,0.77)], income [(AOR);0.45, 95%; CI (0.3, 0.68)], type of solid waste disposal habit [AOR; 0.16, 95%; CI (0.36, 0.66)], source of water [AOR; 0.42, 95%; CI (0.28, 0.65)], shortage of water [AOR; 2.8, 95%; CI (1.88, 4)] were variables identified as predictors for faecal coliform contamination of water in the household. There is high level of faecal contamination of household drinking water in North Gondar Zone. Occupational status, income, solid waste disposal habit, sources of drinking water, and shortage of water were predictor for presence of faecal coliform contamination in household drinking water.

Amendment of Livestock Manure with Natural Zeolite-Clinoptilolite and Its Effect on Decomposition Processes during Composting

The aim of study was to investigate the effect of amendment of cow manure with natural zeolite-clinoptilolite and hydrated lime on decomposition processes over the period of 90 days. Two static piles of amended substrates were constructed consisting of cow manure with an addition of bulking material (2.5% by weight): (1) manure mixed with zeolite (S1); manure mixed with zeolite and lime (S2). Third amendment-free pile served as a control (C). During the experiment, pH level, temperature (T), dry matter (DM), ash, organic matter (OM), C/N ratio, ammonia nitrogen (N-NH4+) and total nitrogen (Nt) were determined. We also determined the counts of total coliform and faecal coliform bacteria and faecal streptococci as indicators of the hygiene level of compost. A significant increase (p ˂ 0.001) in temperature to 53 °C was observed in S2 compared to C. In S2 we observed a significantly reduced release of N-NH4+ from the composting substrate compared to C (p ˂ 0.05). The significant differences were in Nt content in C and S2 (p ˂ 0.001) and between S1 and S2 (p ˂ 0.05). The concentration of Nt increased and caused decrease in the C/N ratio. The content of Nt in the substrates with zeolite increased by 44% in S1 and 45% in S2 compared to C. The differences in counts of coliform and faecal coliform bacteria between C and S2 were significant (p ˂ 0.001). This experiment showed that amendment with zeolite and lime decreased nitrogen losses during composting and indicated sorption effects of zeolite.

Physicochemical, bacteriological, and correlational evaluation of water obtained from boreholes and springs in a sub-urban community

Inadequate safe and portable water supply particularly in underdeveloped and developing countries has been associated with posing serious public health implications, especially as water related diseases continue to be a major health challenge in resource limited settings worldwide. Physicochemical and bacteriological parameters of borehole and spring water sources in a sub-urban community were assessed to determine their potability and correlation index. Twenty (20) water samples, 10 from boreholes and 10 from springs were randomly collected from different locations and analysed using standard microbiological and physicochemical methods. The results were compared with NIS and WHO standards for drinking water. Physicochemical parameters including; temperature, pH, turbidity, electrical conductivity, total hardness, total dissolved solid, Iron, Manganese, Zinc, Chloride, Sodium, Nitrate, Ammonium and Potassium were determined following the procedures prescribed by American Public Health Association Standard Method. Results obtained revealed that 99.3% of the analysed physicochemical parameters were within the maximum acceptable limits of NIS and WHO guidelines for drinking water except borehole iron concentration (0.52mg/L) and Manganese concentration (0.14mg/L). The total heterotrophic bacterial count (THB), total coliform count and faecal coliform count ranged from 1.6x103cfu/100ml to 4.7x103cfu/100 ml, 8.0cfu/100ml to 25cfu/ml, 0cfu/100ml to 14cfu/100ml respectively for boreholes, and 1.7x103cfu/100ml to 4.6x103cfu/100ml, 10cfu/100ml to 21cfu/100ml, 9cfu/100ml to 17cfu/100ml respectively for samples from spring water supply. Phenotypic characterization of the samples revealed the presence of certain organisms with pathogenic potentials such as Staphylococcus aureus 27.5%, followed by E. coli 19.6%, P. aeruginosa 11.8%, Klebsiella spp. 9.8%, Enterobacter spp. 7.8%, Enterococcus spp. 7.8%, Lactobacillus spp. 5.9%, Proteus spp. 3.9%, Shigella spp. 3.9% and Vibrio cholerae 2.0%. Pearson’s correlation analysis showed significantly strong positive correlation between total heterotrophic bacteria count and total coliforms (r = 0.643) and strong negative correlation between pH and total dissolved solids (r = -0.640). Other parameters such as faecal coliform, temperature, pH, turbidity, Zinc, Ammonium and Sodium shows significant correlation among variables.

Comparative assessment of the relationship between coliform bacteria and water geochemistry in surface and ground water systems

The occurrence of pollution indicator bacteria (total and faecal coliform) has been used as a sanitary parameter for evaluating the quality of drinking water. It is known that these indicators are associated with disease causing organisms which are of great concern to public health. This study assessed the relationship between coliform bacteria and water geochemistry in surface and ground water systems in the Tarkwa mining area using logistic regression models. In surface water sources, higher values of chloride (OR = 0.891, p<005), phosphates (OR = 0.452, p<0.05), pH (OR = 0.174, p<0.05) and zinc (OR = 0.001, p<0.05) were associated with lower odds of faecal coliform contamination. In groundwater sources, higher values of phosphates (OR = 0.043, p<0.001), total dissolved solids (OR = 0.858, p<0.05), turbidity (OR = 0.996, p<0.05) and nickel (OR = 6.09E-07, p<0.05) implied non-contamination by faecal coliform. However, higher values of electrical conductivity (OR = 1.097, p<0.05), nitrates (OR = 1.191, p<0.05) and total suspended solids (OR = 1.023, p<0.05) were associated with higher odds of faecal coliform contamination of groundwater sources. Nitrates and total suspended solids, in this case, were completely mediated by the heavy metals. For total coliform in surface water systems, higher values of magnesium (OR = 1.070, p<0.05) was associated with higher odds of total coliform contamination while higher values of phosphates (OR = 0.968, p<0.05) was associated with lower odds of total coliform contamination although the presence of heavy metals completely mediated these relationships. For ground water systems, higher values of pH (OR = 0.083, p<0.05), phosphates (OR = 0.092, p<0.05), turbidity (OR = 0.950, p<0.05) and chloride (OR = 0.860, p<0.05) were associated with lower odds of total coliform contamination. However, higher values of total suspended solids (OR = 1.054, p<0.05) and nitrates (OR = 1.069, p<0.05) implied contamination of total coliform in ground water sources. The relationship between nitrates and total coliform were mediated by the heavy metals. This study establishes the need to monitor, manage and remediate surface and ground water sources for potential disease causing microbes in ways that takes into consideration the factors that create different conditions in the two water systems. This study validates the usefulness of statistical models as tools for preventing surface and ground water contamination.

Evaluation of Coliform and Faecal Coliform Bacteria in the Lakes of Broknes & Grovnes Peninsula at Larsemann Hills, East Antarctica

Purpose: More than 150 lakes on different peninsulas and islands are situated in the Larsemann Hills. The Larsemann Hills are an ice-free area and are located halfway between the Vestfold Hills and the Amery Ice Shelf on the south-eastern coast of Prydz Bay, Princess Elizabeth Land, East Antarctica. Antarctic lakes water is being polluted due to anthropogenic activities caused by various research activities and tourism. Methods: During 34th Indian Scientific Expedition to Antarctica (ISEA) in 2014 to 2015, twenty lake water samples in triplicates were collected from the Broknes & Grovnes peninsula. Coliform and faecal coliform bacteria were analyzed in these samples. Results: Out of twenty, eleven lake water samples were found to be contaminated with coliform bacteria. However, faecal coliform bacteria were absent in all the lake water samples. Coliforms are found in the lakes of Broknes peninsula (P2 Lake & P3 Lake) and Grovnes peninsula (L1C NG, L1D NG, L1E NG, L7 NG, L7A NG, L7B NG, L2 SG, L4 SG & L5 SG). Conclusion: The present study confirms the presence of coliform bacteria in the lakes of East Antarctica which indicates an alarming situation and needs to be investigated further.

Microbiological Quality of Seawater and Mussels (Mytilus galloprovincialis, Lamarck 1819) in the Dubrovnik Coastal Area (Southeastern Adriatic)

This research was conducted between March 2016 and March 2017 as the first study on the water and mussel quality in the coastal area of Dubrovnik (Croatia). Bacteriological analyses were conducted simultaneously on wild mussels (Mytilus galloprovincialis) tissue and their ambient water. The total numbers of heterotrophic bacteria, total coliforms, faecal coliforms and faecal streptococci in the water were determined. Concentrations of Escherichia coli were measured in mussel. The investigated stations are located in coastal water, which is particularly influenced by climatic and anthropogenic factors interacting at the boundaries between the land and freshwater and seawater environments. Seasonal variables, such as rainfall and riverine network characteristics, determine the delivery of bacteria (including E.coli) to coastal water. Direct methods of assessing the density of heterotrophic bacteria at all sampling stations showed the characteristics of an oligotrophic area. The abundance of faecal coliform bacteria was in all cases higher within mussel tissue than in the surrounding water where levels were sometimes undetectable. Maximum E. coli concentrations in mussels and seawater were regularly recorded through the summer, with the exceptions of April 2016 and January 2017 at two stations following precipitation. Minimum faecal coliform concentrations were recorded in the winter.

Physicochemical and Bacteriological Water Quality Parameters in Relation to Land-use Practices at a Rural Catchment, Mbinga District, Tanzania

Data on physicochemical water quality parameters and contamination levels is crucial for protection and sustainable utilization of water resources. This study assessed the physicochemical water quality parameters, faecal coliform bacteria and nutrient loads in water at a catchment used for municipal supply in Mbinga District, Tanzania. Samples were seasonally collected from three areas characterized by distinct geographical features, settlement patterns and land-use practices, and analyzed using standard analytical protocols. Data were subjected to paired-sampled t-test and cluster analysis. The parameters varied as follows: pH (4.75–6.83); temperature (16.4–26.2 ºC); electrical conductivity (14.6–121.1 µS/cm); total dissolved solids (7.0–23.2 mg/L); total suspended solids (BDL–35.5 mg/L); dissolved oxygen (8.6–23.8 mg/L); turbidity (0.1–68.1 NTU); faecal coliform (<1–76 FC/100 mL); nitrite (BDL–0.09 mg/L); nitrate and sulphate were not detected. Spatial variations were associated with land-use disparities. Comparison to risk-based regulatory thresholds for drinking water revealed the levels to be within the acceptable limits, with a few exceptions. Observed seasonal trends indicated an overall decrease in water quality during the wet season. Generally, results showed that water quality at the catchments satisfies requirements for domestic uses. However, the potential contamination risks from human activities call for regular monitoring. Keywords: Physicochemical parameters; faecal contamination; water quality; surface water; Mbinga District

Water quality at the source and incidence of water borne diseases in rural households of South India

Background: The relation of water quality indicators and water borne diseases (WBD) is not properly studied in tropical countries like India. Most of the studies done were cross sectional which reported only point prevalence. This tends to under-estimate and is not adequate to explain the relation. In this context to assess the incidence of water born diseases in relation to household drinking water quality, a longitudinal prospective study was conducted.Methods: The study was conducted in a South Indian state, in a rural area among the members of 300 households by weekly data collection for one year. Water samples were collected and analysis was done thrice corresponding to the climate. Bacterial quality indicators - Total coliform count (TCC), Faecal coliform count (FCC) and E. coli were estimated. The data were processed and analyzed.Results: From 300 households, total 1459 persons were enrolled. During the 12 months period, 72 episodes of WBDs were recorded with incidence rate of 49/1000 person years. Proportional morbidity due to WBD was 11.9%. The WBD reported were ADD, dysentery and hepatitis A. Up to 30% water sources contained E. coli in summer and winter samples and more than 60% in rainy samples. Faecal coliform count was >10 MPN/100 ml in all the seasons in more than 60% water sourcesConclusions: Most of the main water source wells were contaminated. Contamination was more in rainy season. Incidence of WBD has no correlation with water quality indicators in all the seasons (p≥0.05).

Bacteriological and Physicochemical Quality of Mono-pumps and Boreholes used as Sources of Domestic Water Supply in Abonnema Rivers State, Nigeria

Aim: This study was carried out to compare the bacteriological and physicochemical qualities of boreholes and mono-pumps water samples used as sources of domestic water supply, in Abonnema Community, Akuku-Toru Local Government Area, Rivers State. Methodology: A total of forty-eight water samples were collected twice monthly for four months and evaluated. The bacteriological parameters such as total heterotrophic bacterial, total coliform, faecal coliform, Vibrio, Salmonella - Shigella and Pseudomonas were analyzed using standard microbiological methods. The coliform was determined using the Most Probable number technique while, the physicochemical parameters were determined using Standard methods for the examination of water and wastewater. Results: The total heterotrophic bacterial, coliform, faecal coliform, Vibrio, Salmonella-Shigella and Pseudomonas counts of the borehole samples ranged from 7.2×102 - 2.4×103, 2.3×102–4.0×102, 3.6×102-4.8×102, 7.3×102-1.4×103, 2.1×102-2.8×102 and 0.0×100Cfu/ml, respectively. The total heterotrophic bacterial counts, coliform counts, faecal coliform counts, Vibrio counts, Salmonella-Shigella counts and Pseudomonas counts for the mono-pump samples ranged from: 1.1×103- 1.8×103, 2.0×102– 9.1×102, 2.4×102- 3.8×102, 4.5×102-8.6×102, 1.4×102 - 4.2×102 and 0.0×100Cfu/ml, respectively. The bacterial genera identified were: Bacillus, Lynsinibacillus, Staphylococcus, Vibrio, Serratia, Enterobacter, Klebsiella, Shigella, Salmonella, Paenibacillus, Aeromonas and Geobacillus. The means of physicochemical parameters for borehole and mono-pump, respectively were: alkalinity: 41.72±0.01-60.85±0.20 and 29.14±0.01-214.87±1.36mg/l; BOD: 8.26±0.01-10.44±0.0 and 5.12±0.01-5.79±0.01; COD: 126.52±0.01-172.41±0.04 and 83.20±0.44-218.00±0.57; DO: 6.31±0.01 and 3.05±0.07-8.29±0.01; calcium: 5.10±0.28-; 4.83±0.00-10.15±0.00 and 2.71±0.00-14.04±0.00; iron: 2.01±0.00-3.37±0.00 and 1.90±0.00-4.73±0.00; lead: 0.38±0.00-1.07±0.00 and 1.24±0.00-1.63±0.00; nitrate: 0.42±0.00-1.08±0.00 and 1.14±0.00-1.75±0.00; zinc:1.10±0.00-3.18±0.00 and 0.39±0.00-1.82±0.00; phosphate: 0.03±0.00-0.13±0.00 and 0.15±0.00-0.87±0.00; pH: 6.54±0.00-7.05±0.07 and 6.29±0.00-6.93±0.01; salinity: 4.02±0.00-5.14±0.00 and 2.83±0.00-5.88±0.00; total organic carbon: 1.39±0.01-2.81±0.010 and 1.64±0.00-3.42±0.01; polycyclic aromatic hydrocarbon: 32.69±0.00-55.73±0.00 and 45.10±0.00-61.49±0.00mg/l; total petroleum hydrocarbon:58.90±0.00-66.15±0.00 and 60.31±0.00-92.11±0.00 mg/l. Conclusion: The high counts of bacterial groups of public health importance identified from this study, including the presence of: COD, DO, Fe, Pb, Phosphate, Zinc, TPH and PAH in high concentrations reveals contamination of the water sources. Thus, treatment before drinking is recommended.