scholarly journals OCORRÊNCIA DO HERBICIDA TEBUTHIURON NA ÁGUA SUBTERRÂNEA DA MICROBACIA DO CÓRREGO ESPRAIADO, RIBEIRÃO PRETO - SP

Author(s):  
MARCO ANTONIO FERREIRA GOMES ◽  
CLÁUDIO A. SPADOTTO ◽  
VERA LÚCIA LANCHOTTE

Pretendeu-se mostrar que o herbicida Tebuthiuron, selecionado entre outros usados na cultura de cana-de-açúcar, oferece risco de contaminação para a água subterrânea em função de suas características físico-químicas, principalmente, quando aplicado em áreas de recarga direta de aqüíferos consideradas de alta vulnerabilidade natural. Assim, efetuou-se monitoramento do referido herbicida no período compreendido entre 1995 e 1999, coletando amostras de água de poço semi-artesiano, com 53 metros de profundidade, localizado na microbacia do Córrego Espraiado, município de Ribeirão Preto/SP, Brasil, no qual tem sido freqüente o uso do produto em questão. Para efeito de testemunha da amostra de água foi considerado um poço semi-artesiano de profundidade semelhante, localizado cerca de três quilômetros de distância do poço objeto de monitoramento. Os resultados obtidos mostraram que o Tebuthiuron está presente em todas as amostras analisadas, embora em concentrações abaixo do nível crítico para padrão de potabilidade, conforme os limites mais restritivos estabelecidos pela Organização Mundial de Saúde (para os pesticidas em uso é de 0,1 µg/L por pesticida e de 0,5 µg/L para pesticidas totais). Mesmo com os baixos valores de concentração encontrados fica evidente que o Tebuthiuron está atingindo a água subterrânea podendo aumentar sua concentração pela existência de condições ambientais favoráveis à preservação da molécula em profundidade (tais como baixa temperatura, baixa atividade biológica e ausência de luz). Caso o nível crítico seja atingido, o risco de contaminação poderia ser minimizado por meio da substituição do Tebuthiuron por outro herbicida com menor mobilidade no perfil do solo. OCCURRENCE OF THE HERBICIDE TEBUTHIURON IN GROUNDWATER OF ESPRAIADO CATCHMENT RIBEIRAO PRETO - SP (BRASIL) Abstract The herbicide Tebuthiuron, selected among others utilized in sugar-cane crop, shows groundwater contamination risk due to its physicochemical properties, mainly, when applied in direct recharge areas of aquifers considered of high natural vulnerability. In this context, the monitoring of this herbicide in the period of 1995 through 1999 was realized, by collecting water samples of aquifers 53 m depht, located in Espraiado catchment, Ribeirao Preto/SP (Brazil) in which the product has been extensively used. For blank assays it was utilized water samples collected similarly 3 Km away from the monitoring area. The results obtained showed that Tebuthiuron is present in all analyzed samples. Although in lower concentrations of the critical level for drinkable water, following the restrictive limits established by World Health Organization (for pesticides in use is 0,1 µg/L by pesticide and of 0,5 µg/L for total pesticides). Even if the low concentration values found it is evident that the Tebuthiuron affects the groundwater, and could enhance its concentration by favorable ambiental conditions for molecule preservation in deep water (such as low temperature, low biological activity and absence of light). The present scenary reflects contamination risk in case of reaching the critical level, which could only be minimized by the substitution of Thebuthiuron for other herbicide with lower soil mobility.

2020 ◽  
Author(s):  
Saheed A. Adio ◽  
Emmanuel A. Osowade ◽  
Adam O. Muritala ◽  
Adebayo A. Fadairo ◽  
Kamar T. Oladepo ◽  
...  

Abstract. The inherent havoc caused by scarcity of potable water and transmission of water-borne diseases in some parts of Nigeria have created a public health concern. This study seeks to investigate water purification of four different water samples (namely: water from flowing river; freshly dug well or groundwater; rainwater from the rooftop; and heavily polluted dirty water) consumed by the people in the local community using solar desalination method. A single basin solar still was constructed and experimental studies were carried out to determine the influence of solar insolation and temperature variations on the yield of the distillate. The quality of the distillate was tested by measuring the total dissolved solid (TDS) and electrical conductivity. These were compared to World Health Organization (WHO) standard for drinkable water. These parameters were measured for each water sample before and after desalination to determine the efficiency of the solar still. Results showed a wide gap between the values of TDS and EC before and after desalination of the water samples. The values obtained were in accordance with the requirement of World Health Organization for quality drinkable water. The water becomes clear and less turbid after desalination.


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.


2011 ◽  
Vol 8 (1) ◽  
pp. 276-280 ◽  
Author(s):  
Olcay Kaplan ◽  
Nuran Cikcikoglu Yildirim ◽  
Numan Yildirim ◽  
Nilgun Tayhan

The drinking water quality is associated with the conditions of the water supply networks, the pollution and the contamination of groundwater with pollutants of both anthropogenic and natural origin. In this study, water samples were taken from four different waterworks in Tunceli, Turkey and heavy metals concentrations (As, Cu, Cd, Cr, Pb, Ni and Hg) were measured. Four sampling sites were pre-defined in different locations of the city. The obtained results showed that, the heavy metals concentrations in water samples did not exceed the values of WHO (World Health Organization), EC (Europe Community), EPA (Environment Protection Agency) and TSE-266 (Turkish Standard) guidelines.


Sensors ◽  
2019 ◽  
Vol 19 (2) ◽  
pp. 247 ◽  
Author(s):  
Yawen Zhang ◽  
Aiying Ye ◽  
Yuewei Yao ◽  
Cheng Yao

Silver is a common catalyst in industrial production, and the frequent use of Ag+ can cause water pollution. Thus, the detection of Ag+ in the environment is necessary to determine the level of pollution from silver. In this work, we designed a new, highly selective near-infrared (NIR) fluorescent probe QCy to detect Ag+. The probe exhibits “turn-off” fluorescence quenching responses at 760 nm towards Ag+ over other relevant cations, with outstanding sensitivity and a low detection limit (0.03 µM), which is considerably lower than the standard of the World Health Organization (WHO) for drinking water (0.9 µM). Meanwhile, QCy showed a very good linearity at a low concentration of Ag+ with a ‘naked eye’ visible color change of solution from blue to red. The probe has been applied successfully for the detection of Ag+ in real water samples.


2021 ◽  
Vol 5 (2) ◽  
pp. 112-116
Author(s):  
F., F. Akinola ◽  
M., O. Lasisi ◽  
B., S. Awe

Groundwater pollution has increased as a result of poor waste disposal practices in developing countries. The purpose of this study was to determine the levels of physicochemical parameters and heavy metal concentrations in order to investigate the impact of dumpsites on groundwater and soil quality in Erinfun community. Four (4) water samples were collected hand dug well and four (4) soil samples designated Ss1 to Ss4 were collected at distances of 10, 20, 30 and 40 m, respectively, away from the waste dumpsite. Physicochemical parameters and traces such as odour, colour, taste and temperature, as well as Biochemical Oxygen Demand, Chemical Oxygen Demand, Dissolve Oxygen, Total Dissolve Solid, pH, and chloride were measured in collected water samples. Collected soil samples were also analyzed for heavy metals such as Magnesium, Zinc, Iron, Chromium, and Lead. All the physical parameters of the water samples analysed were found not to be within the acceptable limit of World Health Organization and Nigerian Standard of Drinking Water Quality standards. The chemical constituents tested were within the acceptable limit of World Health Organization and Nigerian Standard of Drinking Water Quality except for the Biochemical Oxygen Demand, Chemical Oxygen Demand and Dissolve Oxygen of water samples 1 and 2, respectively. The concentration of trace metals in water sample test were within health limit except for Magnesium and Iron which has the highest concentrations in water sample 1 at 10 m away from dumpsite (61.00 mg/l and 0.46 mg/l). Consequently, open dumpsites are discouraged, and constructed standard landfills with appropriate monitoring guidelines are recommended.


Author(s):  
Sani Mustapha Omolori ◽  
Marcus Danjuma ◽  
Magaji Joshua

The quality of water sources should be tested regularly for various parameters of interest to ensure it meet the standard qualities required for intended use(s). Thus, the suitability of Usuma dam water for domestic use in Nigeria’s Federal Capital Territory Abuja was assessed. The objectives were to assess the properties of Usuma dam water and ascertain its suitability for domestic purpose. A total of thirty (30) water samples were fetched directly. Ten (10) samples each from upstream, downstream and middle were collected. Precautions were taken to prevent sample contamination. Data collected were analyzed as follows: The water properties was analyzed using range and mean, suitability of water properties for domestic purpose was  analyzed by comparing range and mean values with Nigerian Standard for Drinking Water Quality (NSDWQ) and the World Health Organization (WHO) standard for domestic uses. Result showed that water sample were slight acidic (6.83), EC was low (122-180 µs/cm3), TDS (120-144 Mg/l), TSS (1.2-1.7 Mg/l, turbidity (0.29-5.37 Mg/l,) total hardness (7.18-40.46 Mg/l) DO (3.8-4.7 Mg/l), BOD (2.2-4.21 Mg/l), and (25.6-55.4 Mg/l). Minerals nutrients (Ca, Mg, Cl-,Na, K, NO-3 and PO-4. ) in water samples were lower than regulatory standard while heavy metals (Fe, Si, Zn, Pb, Cr, Cd, Cu, Mn, F and B) were relatively higher than regulatory standard. It was concluded that water from Usuma dam are not safe for domestic purpose especially drinking.


Author(s):  
A. Ángeles ◽  
E. Quintero ◽  
I. Gaso ◽  
C. P. Zepeda ◽  
T. Palma ◽  
...  

To assess the quality of drinking water in respect to the content of radioactivity, usually is carried out an screening program in the locations of interest, that program consist in pick representative samples of drinking water from the wells in that locations, water samples are analyzed to measuring the gross alpha/beta radioactivity by a low background proportional counter or a liquid scintillation system. When some sample exceeds the normative limit then it must be known which radionuclides are in that sample. Expected radionuclides in water are the NORM (normal occurring radioactive material) from the natural radioactive chains. 226Ra is frequently present in drinking water and is one of most important radionuclide because its “radiotoxicity”, the WHO [World Health Organization, Guidelines for drinking-water Quality, (2016)] recommends a reference level for 226Ra of 1 Bq/L (the dose coefficient for 226Ra is 2.8 x 10-7 Sv/Bq). From a national program of drinking water screening in the Mexican Republic, the samples that exceeded the national normative limits were picked again in the same well and analyzed by LS (liquid Scintillation), using the method of two phases with a not water miscible scintillator cocktail. Results of concentrations of 226Ra from drinking water are presented. In general the content of 226Ra in drinking water samples was lower that the guide values recommended for the WHO.


2020 ◽  
Vol 27 (4) ◽  
pp. 31-38
Author(s):  
Haneen Khudhair ◽  
Rand Ahmed ◽  
Rim Hussein ◽  
Hassain Ibrahim ◽  
Omer Hassain

he present study was conducted for eight wells that are distributed in A’alam subdistrict in Salah al-Din province to assess the groundwater quality in this area. Water samples from these wells were taken during three months periods, one sample per month. Some physical and chemical properties of the water samples were tested by conducting on-site and laboratory tests. The water temperatures of the wells were recorded to assess its relationship with many properties of the water, including basal. The results indicated that the water of the studied wells was warm during the study period, and its temperature range was (19-24) ° C. The pH was measured and also its values were in the range (7.44-8.4). The values of total dissolved solids exceeded the permissible limits, with a minimum value of (1930) mg/L which is higher than the permissible limit in the drinking water relating to the Iraqi standard and the specifications of the World Health Organization (WHO) and the American Environmental Protection Agency (USEPA), (1000) mg/L. This increase led to a significant increase in the electrical conductivity values, which reached its lowest recorded value of (3940) microsmins/cm, which is above the permissible limit (1500) microsmins/cm. The concentration of chloride ion, which is in the range (482.7-1053) mg/L and sulfur ions, which recorded its lowest value (411) mg/L, and also this exceeded the permissible limits for both ions (250) mg/L according to the Iraqi standard and WHO standards. The study covered all the studied wells water, and its depth are found in the range (80-160) meters, which is very hard water, with a concentration of (180) mg/L. The results indicate that the water was permanently exposed to pollution and is far from optimal for most of the time. Geographic information systems (GIS) were used to produce spatial maps of the study area showing the distribution of the characteristics studied, thus providing a future database for the region, which could be used to diagnose pollution wherever it would be found


mAbs ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 13-25 ◽  
Author(s):  
Clive Metcalfe ◽  
Thomas Dougall ◽  
Chris Bird ◽  
Peter Rigsby ◽  
Marie-Emmanuelle Behr-Gross ◽  
...  

2020 ◽  
Vol 18 (6) ◽  
pp. 1050-1064
Author(s):  
Isabel Cipriani-Avila ◽  
Jon Molinero ◽  
Eliza Jara-Negrete ◽  
Miren Barrado ◽  
César Arcos ◽  
...  

Abstract Chemical elements, which are present in drinking water, could vary due to water sources, treatment processes or even the plumbing materials. Most of these elements do not represent a threat, while others, such as heavy metals, have been proven to cause harmful effects over human and aquatic wildlife. In this study, the quality of drinking water in three cities in Ecuador, Quito, Ibarra and Guayaquil was assessed through a multielement analysis and the heavy metal pollution index (HPI). A total of 102 drinking water samples and six natural water samples were collected and analyzed. Within the scope of analysis, results show that water quality complies with local and international guidelines. HPI did not show significant differences in the water that is supplied to the different neighborhoods of the three cities studied. However, actions should be taken to protect the sources of water, especially in Guayaquil, due to the presence of lead and chromium. For instance, lead was found in 2.8% of the samples in concentrations above World Health Organization (WHO) recommended values. Thus, we suggest to assessing the quality and age of the plumbing system within the whole country, in order to avoid drinking water contamination with heavy metals.


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