scholarly journals A Simple Off-Grid Incubator for Microbiological Water Quality Analysis

Water ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 240 ◽  
Author(s):  
Carolina Bernardes ◽  
Ricardo Bernardes ◽  
Camille Zimmer ◽  
Caetano C. Dorea

There is a need for accessible and low-cost microbiological water quality testing in contexts where diarrheal illness is a major public health concern. In most cases, the quantification of Escherichia coli and other microbial indicators by conventional culture methods requires an incubation step for processed samples at specific temperatures for bacterial growth over a prescribed time. However, incubators can be the most expensive equipment required for such microbial analyses, limiting the number and scope of water quality testing available in low-resource contexts. In this study, a low-cost incubator was developed using a locally available expanded polystyrene (EPS) foam cooler, with two water bottles filled with hot water to heat incubator to a target of 35 °C. The EPS incubator performance was validated by processing 150 water samples in duplicates using the Colilert Quanti-tray/2000 system, incubated in either the EPS incubator or a standard laboratory incubator set at 35 °C. Statistically significant correlations of results indicated that the quantification of E. coli was comparable between both methods. Risk categorizations from standard and EPS incubation results agreed for 141 of 150 (94%) samples, with zero false negatives. In addition to being reasonably mobile the EPS incubator would reduce the cost of such water quality testing, thus potentially increasing the scope of water quality testing coverage.

2020 ◽  
Vol 20 (3) ◽  
pp. 871-877
Author(s):  
Ashish Tambi ◽  
Urmila Brighu ◽  
A. B. Gupta

Abstract Determining the microbial quality of drinking water by assessing the presence/absence (P/A) or enumeration of indicator bacteria continues to be widely practiced worldwide. However, rapid tests are required for microbiological water quality assessment so that the information is available in the shortest possible time for initiating a timely intervention. Traditional methods for the enumeration of indicator bacteria are not only expensive but also need trained personnel. We have developed a low-cost kit, MColiPAT, and have validated its application for detection of coliforms in drinking water using the IDEXX Colilert-18 Quanti tray method. MColiPAT kit medium was able to detect coliforms down to a level of 3.1 MPN/100 ml within 10.5 hours. The sensitivity and specificity of the kit were 95.45% and 100% respectively. MColiPAT is found to be reliable and accurate for the detection of coliforms in drinking water.


Author(s):  
Kadek Diana Harmayani ◽  
Gede Adi Wiguna Sudiartha ◽  
I Wayan Budiarsa Suyasa

<span id="docs-internal-guid-36e28651-7fff-038c-0ab0-ffb60a635785"><span>PT. X is one of the ice companies in which its largest company is located in Bali, more precisely in the Pidada area, North Denpasar. Based on field observations the area is an area that has a calcareous soil structure. The water source of PT. X was extracted from the groundwater. From the field observation, it was found that the pipeline network, that connected the inlet water to water treatment system and ice production units, was severely covered by faint white scale. In order to discover the origin of this scale, water quality testing need to be carried out.  From the results, it was found that the total hardness in the inlet water, taken from the groundwater tap, was 162.85 mg/l with calcium concentration of 2.15 mg/l and iron 3.83 mg/l. Water quality testing was also carried out in the water treatment unit consisting of resin softener where the total hardness surprisingly increased into 279.81 mg/l, calcium concentration was 2.96 mg/l, iron concentration was 0.55 mg/l. Even after being treated in softener resin, the total hardness increased sharply to 483 mg/l, which categorized as extreme hardness. The increase in total hardness indicates that there was a failure in the operation of the water treatment system, even it also contributed to the higher hardness and calcium concentration. This over-year’s treatment failure has been causing accumulation of hardness and calcium concentration in the compartment of both water treatment system and ice production unit that inflicts a higher hardness level in the effluent.</span></span>


2014 ◽  
Vol 4 (3) ◽  
pp. 532-537 ◽  
Author(s):  
Bas Wijnen ◽  
G. C. Anzalone ◽  
Joshua M. Pearce

The developing world remains plagued by lack of access to safe drinking water. Although many low-cost methods have been developed to treat contaminated water, low-cost methods for water-quality testing are necessary to determine if these appropriate technologies are needed, effective, and reliable. This paper provides a methodology for the design, development, and technical validation of a low-cost, open-source (OS) water testing platform. A case study is presented where the platform is developed to provide both the colorimetry for biochemical oxygen demand/chemical oxygen demand and nephelometry to measure turbidity using method ISO 7027. This approach resulted in equipment that is as accurate, but costs between 7.5 and 15 times less than current commercially available tools. It is concluded that OS hardware development is a promising solution for the equipment necessary to perform water quality measurements in both developed and developing regions.


Diversity ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 606
Author(s):  
Guillermo Magallón Ortega ◽  
Carlos Escalera Gallardo ◽  
Eugenia López-López ◽  
Jacinto Elías Sedeño-Díaz ◽  
Martín López Hernández ◽  
...  

Subtropical rivers in developing countries often lack adequate monitoring, which makes it difficult to comprehensively determine their water quality when faced with different anthropic impacts. There are no proper protocols in the regulations to incorporate indicators and adapt them to different biogeographic regions, limiting the potential success of conservation and restoration of river ecosystems. This study proposes implementing macroinvertebrates as bioindicators of water quality in river ecosystems, and modifying the calibration of the widely used Biomonitoring Working Party (BMWP) index for its adaptation in a subtropical river. The Duero River, Mexico, was used as an example in this study. Data were explored with multivariate statistics, and the water quality and habitat values were averaged to obtain the families’ bioindication values and the index categories. The BMWP adequately described a deterioration gradient from the origin to the river mouth (from fair to extremely polluted), with some intermediate recovery points related to the presence of springs. Its performance was compared with other biological indices and exhibited a positive relationship with all of them. In addition, how BMWP changed over time was analyzed by examining previous samples, and highlighted increased river deterioration over time. A calibrated BMWP will allow for long-term monitoring at a low cost.


Author(s):  
Dmitry Petrov ◽  
Kim-Florian Taron ◽  
Ulrich Hilleringmann ◽  
Trudi-Heleen Joubert

Author(s):  
MD. Reza Ranjbar ◽  
Aisha H. Abdalla

<p>Due to the vast increase in global industrial output, rural to urban drift and the over-utilization of land and sea resources, the quality of water available to people has deteriorated greatly. Before the sensor based approach to water quality monitoring, water quality was tested by collecting the samples of water and experimentally analyzing it in the laboratories. However, in today, with time being a scarce resource, the traditional method of water quality testing is not efficient anymore. To tackle this issue, several electronic (microcontroller and sensor based) water quality monitoring systems were developed in the past decade. However, an in depth study of this current water quality testing technology shows that there are some limitations that should be taken into consideration. Therefore, an automatic, remote, and low cost water quality monitoring system has been developed. This system consists of a core microcontroller, multiple sensors, GSM module, LCD display screen, and an alarm subsystem. The quality of water is read from the physical world through the water quality testing sensors and sent to the microcontroller. The data is then analyzed by the microcontroller and the result is displayed on the LCD screen on the device. At the same time, another copy of the sensor readings is sent remotely to the user’s mobile phone in the form of SMS. If an abnormal water quality parameter is detected by any sensor, the alarm system will turn on the respective red LED for that parameter and the buzzer will give warning sound. At the same time, the abnormality of the water parameter is reported to the user through SMS. The system is aimed to be used for wide applications and by all categories of users. It can facilitate the process of water quality monitoring autonomously and with low cost; to help people improve their quality of drinking water, household water supplies and aquaculture farms, especially in rural areas where residents do not have access to standardized water supply and suffer from different diseases caused by contaminated water.</p>


2019 ◽  
Vol 1 (2) ◽  
pp. 123-136
Author(s):  
Kavya Mariya Thomas ◽  
Noel Varghese Mathew ◽  
Rajalekshmi P R ◽  
Rajalekshmi Suresh Kumar ◽  
Reebu Zachariah Koshy

Porous pavements are used to allow infiltration of water for increasing ground water storage. Bio char (Charcoal) is a low cost adsorbent used for the removal of heavy metals and other contaminants. This project examines the possibility of using bio char in porous asphalt mixes and efficiency of the asphalt layer modified with charcoal in removing contaminants from typical storm water. Bio char is added by partial replacement of fine aggregates of size less than 2.36 mm. Preliminary Marshall tests indicated that bio char content of about 1to 2 % is not seriously affecting the properties of porous asphalt mix. Marshall test without charcoal has given the optimum binder content as 5 %. Therefore for the study, samples for Marshall tests were prepared keeping the optimum binder content as 5 % and varying the charcoal content as 1, 1.5 & 2 %. From the drain down, air void, flow and stability requirement it was seen that 1.5 % of charcoal is the optimum. Subsequently for the water quality analysis of water infiltrating through the porous asphalt layer samples are prepared using 1.5 % charcoal. Typical storm water is prepared by adding nitrate & chromium to deionized water. Water quality analysis revealed that charcoal modified asphalt layer can remove 97.2 % nitrate, 56 % of chromium from the storm water, and improve the quality of ground water.


2021 ◽  
Vol 15 ◽  
pp. 117863022110144
Author(s):  
Camille Zimmer ◽  
Alexandra Cassivi ◽  
Celia C Baía ◽  
Elizabeth Tilley ◽  
Robert Bain ◽  
...  

To monitor safely managed drinking water services, an increasing number of countries have integrated water quality testing for Escherichia coli into nationally-representative household surveys such as the Multiple Indicator Cluster Surveys (MICS). However, plastic waste generated during such water quality testing programs, mostly through the use of pre-sterilized disposable materials, is non-negligible. The objective of this study was to evaluate several re-use protocols for disposable filter funnels used by the MICS water quality test kits. Decontamination and re-use protocols were assessed in centralized laboratory and decentralized field settings and neither yielded positive results. Re-use of 100 mL sterile funnels decontaminated with an alcohol wipe resulted in a higher incidence of false positive results (i.e., positive contamination when processing sterile water), both in the laboratory and field; therefore, a higher proportion of positives tests can be expected if these components are re-used. Further improvements to the decontamination technique and training are needed before material re-use can be reliably adopted. Autoclaving the funnels for re-use is feasible, provided that there is capacity to re-package and distribute funnels in a sterile manner.


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