scholarly journals Synthesis of iron oxyhydroxide-coated rice straw (IOC-RS) and its application in arsenic(V) removal from water

2015 ◽  
Vol 13 (3) ◽  
pp. 726-736 ◽  
Author(s):  
Igor W. K. Ouédraogo ◽  
Erol Pehlivan ◽  
Hien T. Tran ◽  
Yvonne L. Bonzi-Coulibaly ◽  
Dieter Zachmann ◽  
...  

Because of the recognition that arsenic (As) at low concentrations in drinking water causes severe health effects, the technologies of As removal have become increasingly important. In this study, a simplified and effective method was used to immobilize iron oxyhydroxide onto a pretreated naturally occurring rice straw (RS). The modified RS adsorbent was characterized, using scanning electron microscope, Fourier transform infrared spectroscopy, thermogravimetric analyzer, and surface area analyzer. Experimental batch data of As(V) adsorption were modeled by the isotherms and kinetics models. Although all isotherms, the Langmuir model fitted the equilibrium data better than Freundlich and Dubinin–Radushkevich models and confirmed the surface homogeneity of adsorbent. The iron oxyhydroxide-coated rice straw (IOC-RS) was found to be effective for the removal of As(V) with 98.5% sorption efficiency at a concentration of <50 mg/L of As(V) solution, and thus maximum uptake capacity is ∼22 and 20 mg As(V)/g of IOC-RS at pH 4 and 6, respectively. The present study might provide new avenues to achieve the As concentrations required for drinking water recommended by the World Health Organization.

2011 ◽  
Vol 63 (10) ◽  
pp. 2143-2148 ◽  
Author(s):  
Hans Sanderson

Trace amounts of pharmaceuticals have been detected in surface waters in the nano- to microgram per liter range, and in drinking water in the nanogram/L range. The environmental risks of pharmaceuticals in surface waters have been evaluated and generally found to be low if the wastewater is treated before release to the environment. The human health risks of trace amounts of pharmaceuticals in drinking water have however not been evaluated in any great depth. Preliminary screening level assessments suggest risk to be low – but the public and decision-makers are concerned and would like the matter investigated more thoroughly, especially with regards to mixture effects, chronic long-term effects and sensitive sub-populations. The World Health Organization is currently evaluating the need for credible health based guidance associated with low concentrations of pharmaceuticals in drinking water. The aim of this paper is to summarize the state-of-the-science and the ongoing international debate on the topic.


2016 ◽  
Vol 13 (1) ◽  
pp. 58 ◽  
Author(s):  
Elad Segal ◽  
Aharon Gedanken

Environmental context The need for detecting and sensing hazardous materials that can contaminate our food and water is growing each and every year. Regulation of these contaminants to safeguard human health depends on the ability to detect them at ultra-low concentrations in the environment. This work proposes a simple and efficient substrate preparation for detecting acrylamide, a toxic and carcinogenic material usually found in drinking water. Abstract Polyacrylamide acts as a very common water purifier worldwide. Unfortunately, it leaves hazardous and toxic residues of its monomer, acrylamide (C3H5NO), in water sources. The World Health Organization (WHO), the Food and Agriculture Organisation of the United Nations (FAO) and the European Union (EU) set the maximum contaminant level of acrylamide in drinking water to 0.1–0.5µgL–1. This environmental risk encouraged our efforts to develop surface-enhanced Raman spectroscopy (SERS) probes that are easy and simple to fabricate, and also have superb detection ability. We report down to 0.071µgL–1 acrylamide detection with good reproducibility, which is even lower than the WHO, FAO and EU requirements, and may be used as a powerful analytical alternative for detection. In this manuscript, we present a practical route to fabricate these detection substrates for detection of ultra-low concentrations of aqueous acrylamide solutions. The facile method is based on deposition of graphene oxide on Si wafers by ultrasonication, followed by surface reduction. These substrates require no adhesion layer or pretreatment with O2 plasma or aminopropyl triethoxysilane for the coating process. Sonochemical deposition of silver nanoparticles on the substrates is also carried out and the product compared with the proposed Si–reduced graphene oxide wafers.


Author(s):  
Dora Cardona Rivas ◽  
Militza Yulain Cardona Guzmán ◽  
Olga Lucía Ocampo López

Objective: To characterize the burden of intestinal infectious diseases attributable to drinking-water quality in 27 municipalities in the central region of Colombia. Materials and methods: A time-trend ecological study. The drinking-water quality of the National Institute of Health and the Institute of Hydrology, Meteorology and Environmental Studies was identified. The disease burden was calculated based on the mortality registered in the National Department of Statistics and the records of morbidity attended by the Social Protection Integrated Information System. The etiological agents reported in morbidity records and the observation of environmental conditions in the municipalities of the study were included. The disease burden was determined according to the methodology recommended by the World Health Organization (WHO).


2021 ◽  
Vol 11 (8) ◽  
Author(s):  
Molla Rahman Shaibur ◽  
Mohammed Sadid Hossain ◽  
Shirina Khatun ◽  
F. K. Sayema Tanzia

AbstractThis study aimed to determine the quality of drinking water supplied in different types of food stalls in Jashore Municipality, Bangladesh. A total of 35 water samples were collected from different tea stalls, street side fast food stalls, normal restaurants and well-furnished restaurants. The water quality was evaluated by determining the distinct physical, chemical and biological parameters. The results revealed that the water used in the food stalls and restaurants for drinking purpose was in desired quality in terms of turbidity, electrical conductivity, pH, total dissolved solids, nitrate (NO3−), sulfate (SO42−), phosphate (PO43−), chloride (Cl−), sodium (Na) and potassium (K) concentrations. The values were within the permissible limit proposed by the Bangladesh Bureau of Statistics and the World Health Organization. Concentrations of calcium (Ca) and magnesium (Mg) found in several samples were higher than the World Health Organization standard. Iron (Fe) concentrations were higher than the permissible limit of the World Health Organization. Only 46% exceeded the permissible limit of Bangladesh Bureau Statistics. The threatening result was that the samples were contaminated by fecal coliform, indicating that the people of Jashore Municipality may have a greater chance of being affected by pathogenic bacteria. The drinking water provided in the street side fast food stalls was biologically contaminated. The findings demonstrate that the drinking water used in food stalls and restaurants of Jashore Municipality did not meet up the potable drinking water quality standards and therefore was detrimental to public health.


2021 ◽  
Vol 232 (8) ◽  
Author(s):  
Ali Chabuk ◽  
Zahraa Ali Hammood ◽  
Nadhir Al-Ansari ◽  
Salwan Ali Abed ◽  
Jan Laue

AbstractIraq currently undergoing the problem of water shortage, although Iraq has two Rivers (Euphrates and Tigris) pass throughout most of its areas, and they have represented a major source of water supply. In the current research, to evaluate the quality of the Euphrates river in Iraq based on the values of total dissolved salts (TDS), the TDS concentrations were collected from sixteen sections along the river in the three succeeding years (2011, 2012, and 2013). The evaluation of the river was done depending on the classification of (W.H.O. (World Health Organization). (2003). Total Dissolved Salts in Drinking-water: Background document for development of W.H.O. Guidelines for Drinking-water Quality. World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland). of rivers for drinking uses. Inverse Distance Weighting Technique (IDWT) as a tool in the GIS was employed to establish the maps of the river that using interpolation/prediction for the TDS concentrations to each selected year and the average values of TDS for these 3 years. Based on the five categories of rivers’ classification of the TDS concentrations according to the (W.H.O. (World Health Organization). (2003). Total Dissolved Salts in Drinking-water: Background document for development of W.H.O. Guidelines for Drinking-water Quality. World Health Organization, 20 Avenue Appia, 1211 Geneva 27, Switzerland), the Euphrates river was classified, and the maps of classification for the years 2011, 2012 and 2013 and the average values for 3 years were created. The average values for 3 years of TDS along the Euphrates river indicated that the sections from SC-1 to SC-4 as moderate-water-quality-Category-3, the sections from SC-5 to SC-10 as poor-water-quality-Category-4, while the sections between SC-11 to SC-16 as very poor-water-quality-Category-5. The interpolation maps showed that the Euphrates river in Iraq was ranged from moderate water quality (Category-3) to very poor water quality (Category-5).


2021 ◽  
Vol 18 (1) ◽  
pp. 1-6
Author(s):  
Roselyn Naidu ◽  
Lionel Joseph ◽  
Syed Sauban Ghani

The current study investigated drinking water quality of samples taken from Arolevu village, a locality situated in Nadi, Fiji. The groundwater samples were collected and subjected to a comprehensive physicochemical and biological analysis. The analysis for the drinking water sample was conducted seasonally, six times a year, that is, three for the dry season and three for the wet season. The results retrieved from the analysis were compared to its maximum contamination levels (MCLs) based on the health-based guidelines provided by the World Health Organization (WHO). The WHO standards were used as an attribute to determine the sources of contaminants likely to be present at the study site. A degradation trend in drinking water quality in the context of climate change may lead to potential health impacts. Hence, it is important to understand seasonal variations in drinking water quality. A proper understanding of the drinking water quality through seasonal water analysis for nitrate, nitrite, potassium, calcium, magnesium and chlorine content as well as its microbiological presence to reduce preventable risks such as using calculated amounts of fertilisers and upgrading the sewerage system to alleviate drinking water contamination is devised through this study.


2018 ◽  
Vol 8 (3) ◽  
pp. 497-507
Author(s):  
Philip Ruciaka Kirianki ◽  
Edward Muchiri ◽  
Natasha Potgieter

Abstract Njoro sub-county in Kenya suffers from constant water shortages causing the residents to rely on both improved and unimproved water sources in the area. The households in the sub-county also use different household storage containers to store drinking water in times when water is not readily available. This study was therefore undertaken to assess selective physico-chemical parameters of water used by the population for drinking purposes using standard assessment methods. A total of 372 water source samples and 162 storage container water samples were tested over a period of three months. Turbidity (0.70–273.85 NTU), iron (0.7–2.10 mg/L), fluoride (0.15–4.01 mg/L), manganese (0.01–0.37 mg/L), and nitrate (0.09–27.90 mg/L) levels in water samples were generally higher than the Kenya Bureau of Standards (KEBS) and/or the World Health Organization (WHO) water quality recommendations for safe drinkable water. The results from this study support the need for continuous monitoring and treating drinking water at the points of collection and of consumption to minimize the long-term health effects on communities consuming this water.


2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
N. Rahmanian ◽  
Siti Hajar Bt Ali ◽  
M. Homayoonfard ◽  
N. J. Ali ◽  
M. Rehan ◽  
...  

The drinking water quality was investigated in suspected parts of Perak state, Malaysia, to ensure the continuous supply of clean and safe drinking water for the public health protection. In this regard, a detailed physical and chemical analysis of drinking water samples was carried out in different residential and commercial areas of the state. A number of parameters such as pH, turbidity, conductivity, total suspended solids (TSS), total dissolved solids (TDS), and heavy metals such as Cu, Zn, Mg, Fe, Cd, Pb, Cr, As, Hg, and Sn were analysed for each water sample collected during winter and summer periods. The obtained values of each parameter were compared with the standard values set by the World Health Organization (WHO) and local standards such as National Drinking Water Quality Standard (NDWQS). The values of each parameter were found to be within the safe limits set by the WHO and NDWQS. Overall, the water from all the locations was found to be safe as drinking water. However, it is also important to investigate other potential water contaminations such as chemicals and microbial and radiological materials for a longer period of time, including human body fluids, in order to assess the overall water quality of Perak state.


Water ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1711 ◽  
Author(s):  
Robert Bain ◽  
Richard Johnston ◽  
Francesco Mitis ◽  
Christie Chatterley ◽  
Tom Slaymaker

The World Health Organization (WHO) and United Nations Children’s Fund (UNICEF), through the Joint Monitoring Programme (JMP), are responsible for global monitoring of the Sustainable Development Goal (SDG) targets for drinking water, sanitation and hygiene (WASH). The SDGs represent a fundamental shift in household WASH monitoring with a new focus on service levels and the incorporation of hygiene. This article reflects on the process of establishing SDG baselines and the methods used to generate national, regional and global estimates for the new household WASH indicators. The JMP 2017 update drew on over 3000 national data sources, primarily household surveys (n = 1443), censuses (n = 309) and administrative data (n = 1494). Whereas most countries could generate estimates for basic drinking water and basic sanitation, fewer countries could report on basic handwashing facilities, water quality and the disposal of waste from onsite sanitation. Based on data for 96 and 84 countries, respectively, the JMP estimates that globally 2.1 billion (29%) people lacked safely managed drinking water services and 4.5 billion (61%) lacked safely managed sanitation services in 2015. The expanded JMP inequalities database also finds substantial disparities by wealth and sub-national regions. The SDG baselines for household WASH reveal the scale of the challenge associated with achieving universal safely managed services and the substantial acceleration needed in many countries to achieve even basic services for everyone by 2030. Many countries have begun to localise the global SDG targets and are investing in data collection to address the SDG data gaps, whether through the integration of new elements in household surveys or strengthening collection and reporting of information through administrative and regulatory systems.


Author(s):  
María Emilia Gavelli ◽  
Laura Carolina Luciani Giacobbe ◽  
Carolina Bustos Fierro ◽  
María Eugenia Olivera

Introduction and objectives: In the context of COVID-19, the World Health Organization has recommended the use of extemporaneously prepared bleach solutions of 1 g/L, as a conservative concentration able to inactivate SARS-CoV-2 and the vast majority of other pathogens that may be present in the healthcare setting. Consequently, there is a renewed interest in conducting stability studies of these solutions. The goal of this work was to verify the available chlorine concentration in several bleach solutions trademarks and to propose a beyond use date for 1 g/L bleach solutions, obtained after dilution with drinking water from different sources. Methods: Bleach trademarks, with nominal concentrations between 25-60 g/L, were subjected to iodometric titration to determine the available chlorine concentration. One trademark was used to prepare 1 g/L dilutions using water from different purification plants in Córdoba, Argentina. The samples were stored at room-temperature, both exposed or protected from light. The available chlorine concentration was determined by titration at preestablished time intervals. The beyond use date was reached when the available chlorine concentration dropped below 90 % of its initial. Results: The concentration of active chlorine in the different trademark bleaches was within the values established by current regulations. Diluted solutions protected from light showed a decrease of less than 10 % in active chlorine concentration during the first 10 days of assay. However, one sample exceeded the acceptance limit after 14 days. In contrast, in the samples exposed to light, the concentration of active chlorine dropped to 96.4 % at 24 hours and 79.3 % after 48 hours. No differences related to drinking water sources were observed. Conclusions: Compliance of the nominal available chlorine concentration in trademark bleach solutions was confirmed. Regardless the water source used for dilution, 1 g/L bleach solutions were stable for 10 days when stored at room temperature and protected from light. Instead, solutions exposed to light maintain their available chlorine concentration for only 24 hours.


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