Coliform Levels Research Articles

Comprehensive evaluation of the possible impact of roofing materials on the quality of harvested rainwater for human consumption

Water is a vital natural resource that influences life and contributes to domestic and industrial activities. Availability and accessibility of safe water sources are crucial for a country's economic growth. Harvesting of roof runoffs is an alternative source of water used for domestic purposes. However, the quality of harvested rainwater can be affected by roofing materials. This research seeks to assess heavy metals concentration, physicochemical and bacteriological parameters in roof runoffs and estimate the water quality index and health risk these metals pose to consumers. Rainwater samples were collected from Aluzinc, Aluminum, Galvanized, and Asbestos roofing materials within the Ejisu municipality. Rainwater collected directly from the sky was used as control. All runoffs from the four roofing materials recorded Cd, Fe, Cr, turbidity, pH, E.coli, total and fecal coliform levels above WHO limit for drinking water. There was a significant variation in pH, EC, Zn, Cd, Cr, Fe, E. coli, total and fecal coliform levels between control samples and roof runoffs (p < 0.05). The estimated water quality index for runoffs from the four roofing materials exceeded 100 indicating their unsuitability for drinking. Cadmium recorded the highest non-cancer health risk to children and adults in all the roof runoffs. Hazard quotients (HQs) above one were recorded for a child (HQ = 40.1) and an adult (HQ = 13.6) via dermal exposure to Cd in runoff from Aluminum roofing material. Hazard quotient of 9.53 and 4.08 were estimated for a child and an adult respectively via oral exposure to Cd in runoffs from Asbestos roofing material. The estimated cancer risks were above 10−3 for a child and an adult via oral and dermal exposure to Cd in all roof runoffs, suggesting a possible cancer health effect. The study concludes that the four roofing materials impact negatively on the quality of runoffs.

COVID-19 lockdown and environmental pollution: an Indian multi-state investigation.

Originating from China, COVID-19 became the first-ever coronavirus pandemic, wreaking havoc in 218 nations. The lack of a potential treatment exacerbated by the inability of the healthcare infrastructure to contain the viral trajectory led to a worldwide lockdown. The anthropogenic halt presented an unprecedented background to quantify the effect of the anthroposphere on environmental pollution. Consequently, we analyzed the variations in the air (PM10, PM2.5, NO2, SO2) and water pollutants (BOD, COD, DO, coliform) using real-time monitoring data in the majorly hit Indian metropolitan states during the lockdown in contrast to 2019 levels. The overall AQI (air quality index) de-escalated by −31.35%, −34.35%, −32.63%, −29.25% in Delhi, Tamil Nadu, West Bengal, and Karnataka, respectively, from the 2019 levels. The daily concentrations of NO2, PM2.5, and PM10 plunged tremendously. The exact pre-disposing factors responsible for higher COVID-19 transmission in some geographical centers remain elusive. Investigations have corroborated putative links between air pollutants and COVID-19 mortalities. Therefore, we further mapped PM2.5, PM10, NO2, and SO2 to co-relate with COVID-19 infectivity and mortality across the study states. Significant (P < 0.001) positive correlation between COVID-19 transmission was established for all pollutants with maximum co-relation with AQI followed by NO2. River Ganga water in Uttarakhand was deemed “fit for drinking” for the first time in two decades. An aggregate of −71.94, −61.32, and −77.94 decrease in BOD, COD, total coliform levels, and an 11.75 rise in the average DO levels from 2019 data. This study will better assist the future framework of health and environment restoration policies.

Microbiological Quality and Heavy Metal Concentrations in Slipper Oyster (Crassostrea iredalei) Cultured in Major Growing Areas in Capiz Province, Western Visayas, Philippines: Compliance with International Shellfish Safety and Sanitation Standards

The increasing demand for slipper oyster (Crassostrea iredalei) has propelled farmers to expand oyster cultivation areas in the Philippines, chiefly for local consumption and feasibly for export overseas. As filter feeders, oysters can accumulate pathogens from the surrounding waters, and these pathogens can cause foodborne diseases in consumers. Therefore, oyster farming areas must be monitored for microbiological quality and heavy metal concentrations. In the present study, the microbiological quality of oysters and their growing waters in the major oyster farming areas of the Cogon and Palina Rivers and Cabugao Bay (in Roxas City and the Municipality of Ivisan, respectively, Capiz Province, Western Visayas, Philippines) were examined monthly during the wet (May to October) and dry (November to April) seasons over 12 months. Regardless of the sampling period, high levels of fecal coliforms in the water and Escherichia coli in oysters were found, clearly illustrating that these oyster growing areas would meet only the class B standard under the European Union classification system and would be considered "prohibited" for growing oysters under the U.S. classification system. Although Salmonella was occasionally detected in oysters, Vibrio cholerae was not detected and Vibrio parahaemolyticus was within acceptable limits. The heavy metal concentrations in oyster meat were also determined during the wet (July) and dry (March) seasons. Zinc and copper were the most abundant metals detected, and concentrations of lead, cadmium, mercury, and chromium were below the regulatory limits set by the European Union and the U.S. Food and Drug Administration. These oyster culture areas should be rehabilitated immediately to improve the microbiological quality of the oysters. Oysters harvested from these sites must be depurated or relayed to ensure quality and safety.

Evaluation of Health Risks Related to the Consumption of Fish from the Gu&amp;#233;ssabo River

Fish is rich in essential nutrients but can remain a potential source of food poisoning. A study was, therefore, carried out with the general objective of highlighting the probable biological and chemical dangers associated with the consumption of fish and freshwater fruits from the Guéssabo river. The present study was conducted on 50 carp fish, 50 mackerel fish, 50 frogs and 50 mollusks caught in the Guéssabo River. Microorganisms were enumerated by conventional tests and heavy metals were investigated by Inductively Coupled Plasma Optical Emission Spectrometry. The enumeration showed high levels of thermotolerant Coliforms (2.5 × 104), Enterobacteriaceae (3.4 × 104), S. aureus (2.3 × 103) and Yeast/Molds (2.1 × 104), in all samples the standards were not in conformity with the required standards. High levels of Al (7230 μg/kg) and Cd (21.57 μg/kg) were observed in carp fish and these values are above the standard. In conclusion, the fish caught in the Guéssabo River could be a health risk factor for the consumer.

Efficacy Assessment of Decentralized Wastewater Treatment Systems in treating Faecal Sludge within Dar es Salaam City

Dar es Salaam Water and Sewerage Authority (DAWASA) considers DEWATS as effective system for faecal sludge management especially from unplanned settlements. No study has been done in Tanzania to assess the treatment efficiency, adoptability and sustainability of the systems. That being the case, this study aimed at assessing the treatment efficiency of the Decentralized Treatment Systems installed within the city. Kigamboni and Mburahati DEWATS were selected as case study areas for the study whereby, quantitative method was used for data collection. The collected results showed that most of the physical parameters were within the allowable range specified by Tanzanian Standards for municipal wastewater discharge (TZS 860:2006). Nitrate and Phosphate levels were within the allowable range at both treatment plants. The BOD5 and COD for Kigamboni DEWATS were four times higher than the maximum allowable safe limit for each. Both Kigamboni and Mburahati DEWATS failed to lower the coliform levels of faecal sludge to meet the maximum allowable discharge standard (10,000 cfu/100 ml) by having the effluent quality of 115,000 cfu/ 100 ml and 22,875,000 cfu/100 ml respectively. Addition of dosing chamber between the gravel filter and polishing dosed at 6mg/l of chlorine remediated the state.

Prevalence of enteric opportunistic pathogens and extended-spectrum cephalosporin- and carbapenem-resistant coliforms and genes in wastewater from municipal wastewater treatment plants in Croatia

Extended-spectrum β-lactamase (ESBL)- and carbapenemase-producing Enterobacterales are a critical global health problem and wastewater treatment plants (WWTPs) can promote their spread into the environment; yet their efficacy is not well characterized. Here, we have used conventional culturing to monitor coliform bacteria and quantitative PCR to monitor 2 ESBL and 5 carbapenemase (CP) genes and 4 enteric opportunistic pathogens (EOPs) in the influent and effluent of 7 Croatian WWTPs in two seasons. In general, levels of total, cefotaxime- and carbapenem-resistant coliforms were significantly reduced but not eliminated by conventional treatment in most WWTPs. Most WWTPs efficiently removed EOPs such as K. pneumoniae and A. baumannii, while E. coli and Enterococcus spp. were reduced but still present in relatively high concentrations in the effluent. ESBL genes (blaTEM and blaCTX-M-32) were only slightly reduced or enriched after treatment. CP genes, blaKPC-3, blaNDM and blaOXA-48-like, were sporadically detected, while blaIMP and blaVIM were frequently enriched during treatment and correlated with plant size, number or size of hospitals in the catchment area, and COD effluent concentration. Our results suggest that improvements in wastewater treatment technologies are needed to minimize the risk of environmental contamination with top priority EOPs and ARGs and the resulting public health.

Microbiome shifts in sprouts (alfalfa, radish, and rapeseed) during production from seed to sprout using 16S rRNA microbiome sequencing

Sprouts harbor high levels of bacteria and have been implicated in massive outbreaks of foodborne illnesses. The elucidation of microbial profiles in sprouts is important; however, little is known about the changes in the microbial composition during production. The present study aimed to define the microbial ecology of sprouts during the stages of production using 16S rRNA metagenome sequencing and culture-dependent methods. Samples of three types of sprouts (alfalfa, radish, and rapeseed) were collected from each stage of production (seed, soaking, germination 1 (Germ 1), germination 2 (Germ 2), sprouting, unwashed, and washed sprouts; n = 105) and subjected to microbiome analyses as well as quantitative and qualitative analyses. Aerobic plate count (APC) and coliforms levels significantly increased within one day (Germ 1) by 3.9–4.4 and 4.2–5.2 log CFU/g, respectively, and levels up to 8.0–9.0 and 6.9–9.0 log CFU/g, respectively, were recorded at the final stage. During production, the microbial communities in alfalfa sprouts simplified into Enterobacteriaceae (80.97–99.29%), whereas the radish and rapeseed sprouts were dominated by microbial communities belonging to two families, the Enterobacteriaceae (radish: 32–43.4%, rapeseed: 24.11–38.39%) and Pseudomonadaceae (radish: 30.53–46.45%, rapeseed: 41.51–57.34%). This suggests that the sprout manufacturing conditions could promote the growth of particular bacterium. Alpha diversity analysis revealed a diverse bacterial community structure in the seeds; however, the diversity sharply declined until Germ 1 and recovered during the production steps thereafter. Beta diversity results suggested that the pattern of microbial composition, and the major shifts in composition, differed by seed type. Significant changes in the bacterial community were observed during the soaking (alfalfa), Germ 1 (radish), and Germ 2 (rapeseed) stages. The present study is the first fundamental report to investigate microbial changes by during the various stages of the sprouting process. The results highlight the potential risk of sprouts regarding foodborne illness and facilitate the determination of effective intervention points during sprout production.

A novel approach to baseline water quality assessment at local and catchment scale: a case study from Berambadi, India.

Optimal design and maintenance are necessary for the sustainability of wastewater treatment systems. In this study, we present the outcome of a novel approach to baseline assessment conducted prior to the design and deployment of a decentralized wastewater treatment system at a school in rural India. The baseline water quality monitoring protocol was deployed to assess (a) the quality and quantity of wastewater (greywater and blackwater) flows from the school and (b) the status of surface water and groundwater quality in the catchment. Hourly greywater flows and water quality trends were monitored across four seasons at the school. Average freshwater consumption at the school was 518 ± 322 L/day for hand washing and 287 ± 97 L/day for cooking meals. Greywater generation showed high hourly variations in COD levels. Greywater generated from hand wash and kitchen sources contributed to 110g/day and 96g/day of BOD5 respectively and 214g/day and 141g/day of COD respectively. Based on additional data from a self-reporting sanitation survey, the organic contaminant load generated from the toilet was estimated to be 1.5 ± 0.1kg COD/day. At the catchment scale, both groundwater and surface water quality were monitored seasonally to assess the impact of raw sewage and stormwater inputs. Compared with borewells, high nitrate-N levels (> 10mg/L) were observed in the village hand pump samples throughout the year. Maximum nitrate-N (16mg/L) and fecal coliforms (3.9 log MPN/100mL) levels were observed in surface waters during monsoons, indicating the impact of sewage and surface runoff on water quality. The proposed approach is useful to estimate data on freshwater use and wastewater generation at the school and hence to make the case for, and design of, a sustainable water management intervention.

Gaseous chlorine dioxide inactivation of microbial contamination on whole black peppercorns

AbstractBlack peppercorn is a common ingredient imported and used in uncooked or ready‐to‐eat foods in the United States. They might be exposed to fecal coliforms and other microbial contamination due to a lack of good agricultural and manufacturing practices in some developing countries under which they were grown and harvested, thus causing economic losses to the peppercorn industry in the United States. We investigated the effect of gaseous chlorine dioxide (ClO2) on reducing the microbial population levels of coliforms, aerobic bacteria, yeasts, and molds on unprocessed black peppercorns. Treatments on peppercorns were conducted in a 30‐L airtight chamber, and equal amounts of dry media precursors were used to generate gaseous ClO2. Whole peppercorns (200 g) were exposed to 20, 30, and 40 g of precursor dose for up to 60 min at 21 ± 0.4°C and in combination with mild heat at 40 ± 2°C. Aerobic bacteria, coliforms, yeasts, and molds on peppercorns were enumerated before (7.4, 7.2, and 7.1 log CFU/g, respectively) and after treatments. Results after treatment demonstrated 0.8–1 log10 (90%) reduction for all the microbes post‐treatment at 21 ± 0.4°C. The treatments conducted with a 30 g precursor dose for 60 min at 21 ± 0.4°C reduced statistically higher (p &lt; .05) microorganisms than those at 40 ± 2°C. Our work demonstrated that gaseous ClO2 could be used as a part of an overall hurdle technology to reduce the coliforms, aerobes, yeasts, and molds on black peppercorns without affecting the visual quality.

Pemanfaatan Elektrik Bioretensi dalam Menurunkan Kadar Escherichia coli dan Total Bakteri Koliform Sebagai Upaya Peningkatan Kualitas Air pada Drainase Perkotaan

Rapid development in a watershed affects surface and ground water sources. Urbanization results in increased environmental pollution and groundwater pollution. Best water resource management practices are Low Impact Development (LID) such as bioretention, vegetative swales, permeable pavements, and rainwater wetlands have been implemented to reduce the adverse effects of urbanization such as flooding by reducing peak runoff on the surface and thereby managing rainwater runoff. The purpose of this study was to analyze microbial contamination in wastewater originating from city drainage channels. The research was carried out experimentally by taking water in Item River, Kemayoran directly and put it in an electric bioretention tank. The rain-wastewater-bioretention (RWB) tank is in the form of a watertight tank measuring 60 cm in diameter by 80 cm in height with a medium of 50 cm, leaving 30 cm to provide space and time for standing water during infiltration time. The results of the water taken on the 2nd day through Bioretention carried out laboratory testing with the scope of Microbiological analysis of Environmental Health Quality Standards, Escherichia coli levels decreased from 17 APM/100 ml to 9 APM/100 ml. In addition, total Coliform levels from 2800 APM/100 ml to 270 APM/100 ml.

Physicochemical and Microbial Quality of Prepackaged Shrimp Processed by a Scaled-Up Microwave-Assisted Induction Heating Technology

A second generation and scaled-up equipment, named Aligo-2TM (microwave-assisted induction heating, MAIH) with a sample capacity of approximately 1.0 L was designed and invented by Bottle Top Machinery Co., Ltd., Taiwan. Pre-packaged raw shrimps were heated in a scaled-up system using heating temperatures of 130 °C and 90 °C for 80 to 150 s, and the physicochemical and microbial qualities were evaluated. The total plate count, psychrotrophic bacteria count, and coliform levels decreased as heating time increased, whereas the cooking loss, color (L*, a*, and W) value, and texture increased. When shrimps were heated for the longest time of 120 s at 130 °C or 150 s at 90 °C, they displayed obvious overcooked, shrunken, and dry appearance. To obtain samples that showed a red color, cooked well, and had no microbial count, better heating conditions for the processing of pre-packaged shrimps via the MAIH scale-up system were 130 °C for 100 s or 90 °C for 130 s. This novel and scaled-up MAIH equipment provides shrimp to be cooked after being packed, thereof avoiding the post-contamination problem.

Assessment of surface water quality of Onuiyieke river in Imo State, Nigeria

This research aimed to assess the surface water of Onuiyieke River to ascertain its quality status. Measurements were made on samples collected from seven locations with 500ml sample bottles according to standard methods. Samples for heavy metals were collected in 250ml bottle and fixed with concentrated HN03. Descriptive analysis, variation plots, ANOVA, Duncan Multiple Range tests, Principal Components Analysis (PCA), Pearson Correlation (r) and Water Quality Index (WQI) were used to analyze data. Mean values of the parameters obtained were: Total Suspended Solids (TSS) 198.19 ± 80.93mg/L; Electrical Conductivity (EC) 331.81 ± 59.78µ; Turbidity 18.84 ± 2.22 NTU; Nitrate ions 14.77 ± 0.92mg/L; Dissolved Oxygen (DO) 6.58 ± O.22mg/L and Biological Oxygen Demand (BOD) 1.77 ± 0.10mg/L. Mean values of the Trace Metals obtained were: Iron (Fe) 1.93 ± 0.23mg/L; Magnesium (Mg)0.22 ± 0.02mg/L and Calcium (Ca) 15.15 ± 1.87mg/L while the mean value of Faecal Coliform was 1.91 ± O.10MPN/100. pH, EC, TSS, BOD, turbidity, N03-, Ammonia, Fe and Faecal coliforms exceeded the NESREA and WHO maximum permissible limits. There were significant spatial differences in levels of TDS, EC, NO3, NH3, DO and Faecal coliforms (Sig F=0.000 to 0.039) and significant temporal differences in levels of PO43- (Sig F= 0.078 to 1000) between the control and other locations at p&lt;0.05. Four Principal Components (PCs) formed the extraction solution with a cumulative percentage variability of about 77.67%. The Water Quality Index revealed that the rating for the water quality across the sampling locations was between excellent and unsuitable. Appropriate monitoring procedures for the sustainable development of the river should also be put in place.

Effects of seasonal changes and environmental factors on bioindicator bacteria levels in Çardak Lagoon, Çanakkale Strait, Turkey

Abstract Çardak Lagoon is one of the most important marine environments in the Turkish Strait system, which is home to a variety of organisms. The lagoon is currently under stress and faces the risk of heavy pollution. For this reason, the present state of the lagoon was monitored in this study. During sampling from October 2018 to June 2019, the levels of indicator microorganisms fluctuated up to 4.04 Log10 cfu 100 ml−1 and their presence was found to be higher in warmer seasons. The highest positive correlations were observed for total coliform levels with salinity and chemical oxygen demand, whereas the highest negative correlations were found between the levels of fecal coliforms, pH and temperature. E. coli and fecal streptococci showed moderate correlations with the environmental factors in all seasons. Although nitrite and nitrate (NO2 + NO3) were not significantly correlated with bacteria levels, they were present at elevated levels. Çardak Lagoon showed the lowest microbiological and chemical quality in the summer season, and this situation continued into the autumn season as a possible result of increased wastewater discharge and human activities. The lagoon should therefore be monitored regularly and precautions should be taken to prevent severe ecological deterioration.

Agro-ecological Characterization of Vermicomposted Sewage Sludge from Municipal and Poultry Enterprise Wastewater Treatment Plants

The purpose of this study was to make an agro-ecological characterization of vermicompost (VC) produced from sewage sludge (SS). As a substrate, SS from municipal and poultry meat processing enterprise wastewater treatment plants (MTP and PTP, respectively) was utilized. The substrates were vermicomposted by Red Californian earthworm (Lumbricus rubellus) for 120 days. For VC quality assessment, 19 physicochemical and 6 microbiological parameters were used. The evaluation of physicochemical parameters was done according to ISO standard methods and microbiological analysis-by plating 1 mL of sample dilutions on selective, chromogenic culture medium sheets. It was found that the vermicompost from MTP (VC-M) had higher levels of EC, mineral elements (N, P and K compounds in forms available to plants), heavy metals (Mn, Cu, Zn, Cr, Ni, Pb, Cd) and coliforms, and lower levels of pH, TOC, C/N ratio, Fe, total plate count (TPC), Enterobacteriaceae and Salmonella spp. counts compared to VC from PTP (VC-P). During the vermicomposting process, the substrates from both wastewater treatment plants (TPs) showed similar trends towards decrease in pH, TOC, N-NH4+, C/N ratio, TPC, coliforms, E. coli, Enterobacteriaceae and Salmonella spp. counts, whereas the opposite trends were established for EC, TKN, N-NO3-, TP, P2O5, TK, and K2O values. The vermicomposting had a negligible effect on heavy metal concentrations. In the final substrates E. coli were not detected, while the bacterial spore forms (Clostridium perfringens) were not eliminated. The final substrates cannot be used as fertilizers or soil amendments because of the presence of Salmonella spp. and C. perfringens over the permissible limits according to EU and Bulgarian regulations.

Using machine learning to reveal spatiotemporal complexity and driving forces of water quality changes in Hong Kong marine water

A self-organizing map (SOM), which is an unsupervised neural network, is used to explore the spatiotemporal variability of water quality in Hong Kong marine water areas based on 31 years of monitoring data (1986–2016). In this study, three types of SOMs, referred to as s-v, s-t and t-s SOM, respectively, are applied to the multivariate marine water quality data, and principal component analysis (PCA) is used to help the clustering of SOM neurons and component planes. The major findings revealed by the spatiotemporal SOM analyses include the following: a) Hong Kong marine water areas can be classified into five regions with distinctive water quality characteristics over the long term, b) the spatiotemporal variations in chlorophyll-a (Chl-a) and NO3− are greatly affected by ocean currents and nutrients from Pearl River discharge, c) marine water quality is significantly affected by water control projects, e.g., the Hong Kong Harbor Area Treatment Scheme (HATS), and d) nitrogen (N) is the limiting nutrient for phytoplankton growth in winter, west and south of the Hong Kong marine regions, while phosphorus (P) is the limiting nutrient in summer, owing to the massive discharge of the Pearl River that contain NO3−. Furthermore, the severe pollution in Deep Bay with high levels of Chl-a, nutrients and fecal coliform (FC) deserves immediate attention from the governments. The results of this study prove that combined spatiotemporal SOM analyses provide a powerful tool to identify spatiotemporal patterns in water quality data and to reveal the driving forces behind water quality changes. This study presents the first attempt to apply SOMs to water quality analysis at both spatial and temporal domains.

Native forest cover safeguards stream water quality under a changing climate.

Ensuring a sufficient and adequate supply of water for humans and ecosystems is a pressing environmental challenge. The expansion of agricultural and urban lands has jeopardized watershed ecosystem services and a changing climate poses additional risks for regional water supply. We used stream water quality data collected between 2000 and 2014, coupled with detailed precipitation and land cover information, to investigate the effects of landscape composition and short-term precipitation variability on the quality of water resources in the state of São Paulo, Brazil. The state is home to over 45 million people and has a long history of human landscape modification. A severe drought in 2014-2015 led to a major water crisis and highlighted the fragility of the regional water supply system. We found that human-dominated watersheds had lower overall water quality when compared to forested watersheds, with urban cover showing the most detrimental impacts on water quality. Forest cover was associated with a better overall water quality across the studied watersheds, with forested watersheds having low turbidity and high dissolved oxygen. High precipitation led to increased turbidity and fecal coliforms levels and lower dissolved oxygen in streams but these effects depended on watershed land cover. High precipitation diluted concentrations of nitrogen and dissolved solids in highly urbanized watersheds but exacerbated turbidity in pasture-dominated watersheds. Given the high costs of water treatment in densely populated regions, there is a pressing need to plan and manage landscapes in order to ensure adequate water resources. In tropical regions, maintaining or restoring native vegetation cover is a promising intervention to sustain adequate water quality.

The importance of water quality in classifying basic water services: The case of Ethiopia, SDG6.1, and safe drinking water.

IntroductionSustainable Development Goal (SDG) 6 aims to coordinate international efforts toward “clean water and sanitation.” However, water contaminated with pathogenic bacteria or thermotolerant coliforms (TTC) will not achieve the SDG target of clean water in the lives of people around the world. The aim of this study is to assess the water quality parameters of basic water services in Amhara and Afar regions of Ethiopia as well as the role and importance of local managerial committees in ensuring basic water functionality.MethodsThis mixed methods research, conducted in January-June 2019, sampled 22 districts from food-insecure areas in the Amhara and Afar regions of Ethiopia. From the 22 districts, which represent nearly one third of all districts in each region, 111 water services classified as “basic” were randomly selected. For each selected water service, research included: water quality sample testing, visual observation of water services, interviews and focus group discussions with the associated water managerial committee members. Descriptive statistics frequency, percent, mean, median, standard deviations, normal tables, cross-tables and graphs are used to present the data.ResultsAlthough the international water standard for thermotolerant coliform (TTC) levels is 0 CFU/100ml, in our sample of 111 water services, the maximum TTC counts were 71 CFU/100 ml and the mean was 4 CFU/100 ml. Thermotolerant coliform counts were above the permissible standard values for nearly 40% (n = 111) of the basic water services. TTC was detected in 44 (39.64%) (n = 111) basic water services. Of these, 38 (34.23%) were operationally functional while 6 (5.41%) were not functional. Approximately one third of the basic water services sampled, deemed “functional” by international standards, do not provide potable water due to thermotolerant coliform (TTC) levels.ConclusionOur findings from the Amhara and Afar regions of Ethiopia demonstrate that water quality parameters are not currently considered in classifying basic water services. This suggests that international efforts to address SDG 6 should incorporate water quality as a key parameter to better track international progress toward “clean water and sanitation” efforts. We discuss two potential pathways for stronger inclusion of water quality parameters in international definitions: (1) to mandate water quality within “functional” and “non-functional” definitions or (2) to add a ladder rung titled “safe basic water services” to the international drinking water ladder. Our findings from Ethiopia suggest that additional research should be undertaken in development contexts to assess whether or not “functional” basic water services provide safe drinking water to users.

Groundwater contamination and health risk assessment across an urban gradient: Case study of Onitcha metropolis, south-eastern Nigeria

Urban population growth in south-Eastern Nigeria and associated proliferation of built-up areas predispose groundwater to contaminants of anthropogenic origin. This study compared the groundwater quality across an urban gradient, in Onitsha, a notable urbanized region and beehive of commercial activity in southeastern Nigeria. Groundwater samples (n = 120) from sixty boreholes tapping into aquifers spanning major settlement clusters at upper Iweka, Mgbuka and Nkpor, were sampled over 5-months from August to December 2019. Faecal coliforms, water-soluble metals, and nutrients (nitrates and phosphates) were estimated in groundwater samples. Noncarcinogenic risks of heavy metals in ground water samples was estimated for Average daily dose (ADD) and Total Hazard Quotient (THQ) using both deterministic and probabilistic approaches. Concentrations of mercury and heavy metals (Fe, Pb, and Cd) estimated in water samples revealed a general exceedance of World Health Organization (2009) standards for drinking water. However, significantly higher Hg, Pb and faecal coliform levels (0.122 ± 0.03 mg/L, 0.115 ± 0.014 mg/L, 2.3 × 106 ± 300 MPN respectively) in groundwater of the more built-up areas of upper Iweka highlight increased chances of metals and pathogens impacts on water quality with increased urbanization. High incidence of nutrients (nitrates: 258.40 ± 62.1 and phosphorus: 33.05 ± 4.06 mg/L) in groundwater of less urbanized areas suggests impacts of fertilizer applications from greater agricultural activity. Probabilistic estimates for heavy metals in ground water from Onitsha via ingestion route, showed that Upper Iweka had the highest HQ (3.262) followed by Mgbuka (2.1233) and Nkpor (2.0187). On the other hand, estimates showed that Mgbuka had the highest HQ (0.0241) followed by Nkpor (0.016) and Upper Iweka (0.014) for dermal exposure routes. Strategic mitigation measures including urban planning and infrastructural upgrade are recommended to protect the water resources, prevent further groundwater contamination and reduce population health risks emanating from poor drinking water sources.

Investigating Salmonella enterica, Escherichia coli, and Coliforms on Fresh Vegetables Sold in Informal Markets in Cambodia

Vegetables in Cambodia are commonly sold in informal markets lacking food safety standards and controls. Current data on microbial contamination of vegetables in Cambodian informal markets are limited. The purpose of this study was to investigate Salmonella enterica and indicator organisms (Escherichia coli and coliforms) on the surface of fresh vegetables sold in informal markets in Cambodia. Samples of loose-leaf lettuce, tomatoes, and cucumbers were collected from 104 vendors at four informal markets in Battambang and Siem Reap provinces during the rainy and dry seasons. Detection methods for S. enterica were adapted from the U.S. Food and Drug Administration's Bacteriological Analytical Manual. Coliform and E. coli populations were quantified by plating onto E. coli/coliform count plates. S. enterica was most prevalent on lettuce during the dry season (56.5%, 95% confidence interval [CI] [41.0, 70.8]) than during the rainy season (15.4%, 95% CI [7.5, 29.1]), whereas no significant seasonal differences were apparent for tomatoes and cucumbers. Regardless of season, levels of S. enterica were highest on lettuce (5.7 log CFU/g, 95% CI [5.5, 5.9]), relative to cucumbers (4.2 log CFU/g, 95% CI [3.8, 4.6]) and tomatoes (4.3 log CFU/g, 95% CI [4.1, 4.6]). For E. coli, prevalence was higher during the rainy season (34.0%, 95% CI [25.4, 43.8]) than during the dry season (9.1%, 95% CI [4.9, 16.5]), with the highest prevalence estimated on lettuce. Coliform levels on lettuce and tomatoes were greater during the rainy season (6.3 and 5.3 log CFU/g, 95% CI [5.7, 6.8] and [4.7, 5.8], respectively) than during the dry season (5.2 and 3.9 log CFU/g, 95% CI [4.7, 5.7] and [3.4, 4.4], respectively). These results indicate seasonal patterns for microbial prevalence in lettuce and an overall high level of bacterial contamination on raw vegetables sold in Cambodian informal markets.

Effect of Replacing in-Feed Antibiotic Growth Promoters with a Combination of Egg Immunoglobulins and Phytomolecules on the Performance, Serum Immunity, and Intestinal Health of Weaned Pigs Challenged with Escherichia coli K88.

Simple SummaryPost-weaning diarrhea (PWD) in pigs caused by Escherichia coli (E. coli) is a global problem which results in substantial economic losses, due to decreased performance and a high incidence of mortality and morbidity. Due to the banning of antibiotic growth promoters (AGPs) by many countries, it would be valuable to find environmentally friendly and non-antibiotic alternatives to AGPs and to evaluate their effectiveness. Both immunoglobulins and phytomolecules are separately reported as benefiting animal growth, but the efficiency of combinations of immunoglobulins and phytomolecules as AGP alternatives is largely unknown. In this study, the results showed that a mixture of immunoglobulin and phytomolecule administration had positive effects on feed efficiency, diarrhea reduction, intestinal morphology, and coliform control. Combinations of immunoglobulins and phytomolecules can be used as a potential alternative to AGPs in weanling piglets.The study was conducted to investigate the effects of replacing antibiotic growth promoters (AGPs) with an egg immunoglobulin (IgY) combined with phytomolecules (PM) on the growth rate, serum immunity, and intestinal health of weaned pigs challenged with Escherichia coli K88 (E. coli K88). A total of 192 piglets were weaned at 28 days old with an average weight of 7.29 (± 0.04) kg. They were randomly divided into four treatments containing eight replicates with six piglets per replicate. The treatment groups were NC and PC fed a basal diet, AGP fed a basal diet supplemented with 75 mg/kg chlortetracycline, 50 mg/kg oxytetracycline calcium, and 40 mg/kg zinc bacitracin, IPM fed a basal diet supplemented with IgY at dose of 2.5 g/kg and 1.0 g/kg and PM at dose of 300 mg/kg and 150 mg/kg during days 1 to 17 and 18 to 42, respectively. On days 7 to 9 of the experiment, piglets in the PC, AGP, and IPM groups were orally challenged with 20 mL E. coli K88 (109 CFU/mL), while piglets in the NC group were challenged with 20 mL medium without E. coli K88. The E. coli K88 challenge model was successful as the incidence of post-weaning diarrhea (PWD) of piglets challenged with E. coli K88 was significantly higher than that of those unchallenged piglets during the challenge time (days 7 to 9) and days 1 to 7 of post-challenge (p < 0.05). A diet with combinations of IgY and PM and AGPs significantly decreased the incidence of PWD during the challenge time and days 1 to 7 of post-challenge (p < 0.05) compared to the PC group and significantly improved the ratio of feed to weight gain (F:G) during days 1 to 17 of the experiment compared to the NC and PC groups (p < 0.05). In comparison with the PC group, piglets in the IPM group had significantly higher serum levels of IgA, IgG, and IgM (p < 0.05), but lower serum IL-1β on day 17 of experiement (p < 0.05). Besides, diet supplementation with AGP significantly decreased serum IL-1β, IL-6, and TNF-α on days 17 and 42 (p < 0.05) with comparison to the PC group. Piglets in the IPM group showed a significantly lower level of fecal coliforms (p < 0.05), but a higher villus height of jejunum and ileum and higher ratio of villus height to crypt depth of duodenum and jejunum (p < 0.05) than those piglets in the PC group. In summary, diet supplementation with a mixture of IgY and PM decreased the incidence of PWD and coliforms, increased feed conversion ratio, and improved intestinal histology and immune function.