scholarly journals OCCURENCE OF HEXAVALENT CHROMIUM IN THE OPHIOLITE RELATED AQUIFERS OF LOYTRAKI AND SCHINOS AREAS

2017 ◽  
Vol 50 (4) ◽  
pp. 2261 ◽  
Author(s):  
K. Pyrgaki ◽  
A. Argyraki ◽  
E. Kelepertzis ◽  
V. Paraskevopoulou ◽  
F. Botsou ◽  
...  

The main objective of the present study is to assess Cr(VI) concentrations in groundwater and surface water of Loutraki and Schinos areas. Totally, 38 samples were collected from both areas from April to May 2015. Both surface water and groundwater are of bicarbonate-magnesium type (Mg-HCO3 -) and present very high concentrations of Mg2+ (up to 266mg/L) whereas the Cr(VI) concentrations vary among the different water groups (<1,6μg/L-120μg/L). Only 2 out of 15 boreholes of Loutraki area have chromium concentrations above the permissible level for drinking water (50μg/L for Cr(tot)) with the maximum Cr(VI) concentration being 74μg/L. In the area of Schinos, three wells have also high concentrations of Cr(VI) ranging from 40μg/L to 120μg/L. The absence of industrial activity in both areas is indicative of the geogenic origin of Cr(VI) in groundwater which is probably related to the dissolution and oxidation of primary Cr bearing minerals derived from ophiolithic rocks of Geraneia Mountains.

Water ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 392 ◽  
Author(s):  
Sabir Nurtazin ◽  
Steven Pueppke ◽  
Temirkhan Ospan ◽  
Azamat Mukhitdinov ◽  
Timur Elebessov

The thinly populated Balkhash District of Kazakhstan’s Almaty Region lies in the lower reaches of the Ili-Balkhash basin, which is shared by China and Kazakhstan. The district is arid and heavily dependent on inflows of surface water, which are threatened by the effects of upstream population growth, economic development, and climate change. The quality of drinking water from centralized water systems and tube wells in nine villages of the district was analyzed, and the organoleptic properties of water from these sources was also assessed by an expert and via surveys of local residents. Although most samples met governmental standards for the absence of chemical impurities, high concentrations of mineralization, chlorides, boron, iron, and/or uranium were present in some well water samples. Levels of these pollutants were as much as 4-fold higher than governmental maxima and as much as 16-fold higher than concentrations reported previously in surface water. All centralized water samples met standards for absence of microbial contamination, but total microbial counts in some well water samples exceeded standards. Organoleptic standards were met by all the water from five villages, but centralized water from one village and well water from four villages failed to meet standards based on expert judgment. Residents were, for the most part, more satisfied with centralized rather than well water, but there was no obvious relationship between the failure of water to meet standards and the locations or populations of the settlements. This is the first comprehensive assessment of groundwater used for drinking in the lower Ili-Balkhash basin, and although it relies on a limited number of samples, it nevertheless provides evidence of potentially serious groundwater contamination in the Balkhash District. It is thus imperative that additional and more detailed studies be undertaken.


2005 ◽  
Vol 3 (1) ◽  
pp. 77-82 ◽  
Author(s):  
Floyd Frost ◽  
Tim Muller ◽  
Gunther Craun ◽  
Kádár Mihály ◽  
Berencsi György ◽  
...  

We compared serological responses to Cryptosporidium parvum antigens using surplus sera from females undergoing routine screening for pregnancy from three counties in Hungary where bank-filtered surface water, conventionally filtered and disinfected surface water, and groundwater from either a karst or confined aquifer are commonly used for drinking water. The primary purpose was to determine whether the prevalence and intensity of serological responses, indicators of prior Cryptosporidium infection were similar for these populations. Women using groundwater from a confined aquifer had significantly lower mean serological responses for both the 15/17-kDa and 27-kDa (p&lt;0.0001) antigen groups than women using conventionally filtered and disinfected surface water or karst well water. This is suggestive of less frequent infections. Women using bank-filtered water also had lower mean responses for both antigen groups. Among women using bank-filtered water, the mean intensity of response for both antigen groups was almost one-third of the mean response observed for women using conventionally filtered and disinfected surface water. These findings suggest that riverbank filtration may be an effective alternative to conventional treatment for reducing Cryptosporidium exposures and infection from surface drinking water sources.


2020 ◽  
pp. 161-199
Author(s):  
Nadhir Al-Ansari ◽  
Sabbar Saleh ◽  
Twana Abdullahand ◽  
Salwan Ali Abed

Insufficiency of water resources in the Middle East Region represents vital factors that influence the stability of the region and its progress. Expectations indicate that the condition will be dimmer and more complicated, especially in Iraqi territory. Iraq, which is situated in the Middle East, it covers an area of 433,970 square kilometers and populated by about 32 million inhabitants. Iraq greatly relies in its water resources on the Tigris and Euphrates Rivers as a surface water resources, and several productive groundwater aquifers in which from the hydrogeological point of view divided into several major aquifer units including Foothill, Al-Jazira, Aquifer System, Mandali-Badra-Teeb, Mesopotamian and Desert Aquifer system. Recently, Iraq is suffering from water shortage problems. This is due to external and internal factors affecting the water quality of water resources; they are controlled and uncontrolled factors. The uncontrolled factors are climate change and its consequences, such as reduction of precipitation and temperature increasing. The controlled factors have a significantly negative influence on water resources, but their effects involve more specific regions. The controlled factors are mainly represented by building dams and irrigation projects within the upper parts of the Tigris and Euphrates catchments, Al-Tharthar Scheme, waste water, solid wastes and wastes from wars, which has a significant effect on surface water in Iraq because about 80% of the water supply to Euphrates and Tigris Rivers come from Turkey. In addition, the pressures resulting from the high demand for water resources, and the continued decline in their quantity rates have led to major changes in the hydrological condition in Iraq during the past 30 years. The decrease in surface water levels and precipitation during these three decades reflects the drop in the levels of water reservoirs, lakes, and rivers to the unexpected levels. The level of main country’s water source, Tigris, and Euphrates Rivers has fallen to less than a third of its natural levels. As storage capacity depreciates, the government estimates that its water reserves have been reduced precariously. According to the survey from the Ministry of Water Resources, millions of Iraqi people have faced a severe shortage of drinking water. Since of the importance of water for human life and the need to monitor temporal and spatial changes in quality and quantity, there is a need to develop a general Iraqi Water Quality Index (Iraq WQI) to monitor surface water and groundwater and classify it into five categories, very good, good, acceptable, bad and very bad, in terms of suitability for domestics, irrigation and agriculture depending on the Iraqi and WHO standards for drinking water. In addition, strict establishment for the regular quantitative monitoring surface water and groundwater setting and processes. Prospects are more negative for all riparian countries. This implies that solving these problems requires actual and serious international, regional, and national cooperation to set a prudent plan for water resources management of the two basins. Iraq being the most affected country should seriously set a prudent, scientific, and strategic plan for the management and conservation of its water resources. Keywords: Pollution, Water Quality, Waste, Surface water, Groundwater, Iraq.


2014 ◽  
Vol 65 ◽  
pp. 381-388 ◽  
Author(s):  
Mina Suh ◽  
Chad M. Thompson ◽  
Christopher R. Kirman ◽  
Michael C. Carakostas ◽  
Laurie C. Haws ◽  
...  

2020 ◽  
Vol 5 (3) ◽  
pp. 30-54
Author(s):  
R. A. Mikailova ◽  
D. N. Kurbakov ◽  
E. V. Sidorova ◽  
I. V. Geshel ◽  
N. V. Andreeva ◽  
...  

The paper presents experience of developing and maintaining a system of radioecological monitoring of freshwater ecosystems in the vicinity of Rooppur Nuclear Power Plant (Bangladesh). Components of freshwater ecosystems in the zone of NPP impact are both very informative for determining the environmental state and very important for conducting economic activities. Therefore, the issue of assessing and predicting quality of freshwater ecosystems in the vicinity of NPP is relevant for ensuring radiation and environmental safety. During the studies, we developed a detailed monitoring program; selected observation points for the state of surface water and groundwater at different distances from Rooppur NPP; determined monitoring objects (water, bottom sediments, higher aquatic vegetation, and fish), list of parameters to be studied, observation regulation, methods, and regulatory and technical support. Among the indicators controlled we considered the following ones: physicochemical properties of water and bottom sediments; radionuclide content of components of freshwater ecosystems including natural (40K, 226Ra, and 232Th) and technogenic (90Sr, 137Cs, and 3H) radionuclides; and content of 19 heavy metals, as well as chemical pollutants. Monitoring studies were conducted in 2014–2017, considering climatic peculiarities of the region at different periods of the year. Radionuclides in environmental objects were determined by spectrometry and radiochemistry; heavy metals – by atomic absorption and plasma emission analysis methods. It was established that higher aquatic vegetation in the Padma River is found not in all seasons. In December, it was almost absent. The maximum species diversity was registered in June. Differences between surface water and groundwater in the vicinity of Rooppur NPP were distinguished for several physical and chemical characteristics. Values of drinking water total mineralization and hardness were higher than that of surface water by 2–3 times. This is due to Padma River water composition, the basis of which is meltwater and rainwater. Organic pollutants content in surface water and groundwater was below detection limits or at minimum ones (benzopyrene – less than 0.01 μg·L−1; phenols – 1.3–3.5 μg·L−1; and petroleum products – 0.01–0.043 mg·L−1). Activity concentration of 137Cs in Padma River water did not exceed 0.18 Bq·L−1 (with a mean of 0.07 Bq·L−1) during the observation period. The content of 90Sr was 0.02–0.12 Bq·L−1, and the concentration of 3H varied in the range of 0.8–2.1 Bq·L−1. Mean specific activity of 90Sr in bottom sediments was 0.5–1.8 Bq·kg−1, and 137Cs – 0.8–2.1 Bq·kg−1. Specific activity of 3H in bottom sediments was less than 3 Bq·kg−1, except for 3 samples in 2017 (12–30 Bq·kg−1), which was most likely due to a local pollution. Specific activity of 90Sr in higher aquatic vegetation was 0.4–3.9 Bq·kg−1, and 137Cs – 0.4–1.0 Bq·kg−1. In drinking water, activity concentrations of radionuclides were as follows: 137Cs – 0.03–0.27 Bq·L−1; 90Sr – 0.01–0.16 Bq·L−1; 3H – 0.4–1.2 Bq·L−1. Specific activity of 90Sr in fish was 0.02–1.6 Bq·kg−1.The content of 137Cs in fish was 0.26–0.3 Bq·kg−1. Analysis of monitoring data on heavy metal levels in components of freshwater ecosystems in the vicinity of Rooppur NPP showed that for a number of elements their increased concentrations were recorded, most of which belong to monsoon season. In Padma River surface water, a repeating increase in As, Cd, Mn, and Al concentrations was noted, and in bottom sediments – an increase in As, Cd, Ni, Co, and Zn content, which was associated with anthropogenic impact and increasing runoff of pollutants during monsoon rains. Repeatedly increased As and Mn concentrations were noted in drinking water of Rooppur NPP 30-km zone. In separate samples, there was an increase in Fe and Al content. This might be due to both natural peculiarities of the region (relatively high As content in aquifers) and the state of water supply systems. Obtained results and developed network of radioecological monitoring of freshwater ecosystems would make it possible to register a change in the situation and to identify impact of Rooppur NPP operation on human population and the environment.


2000 ◽  
Vol 42 (1-2) ◽  
pp. 403-407 ◽  
Author(s):  
N. Azbar ◽  
A. Türkman

Although water supplies containing excessive amount of fluoride are generally very rare worldwide, there are locations in Turkey where drinking water contains very high fluoride concentrations. Especially in the middle and eastern part of Turkey, some mineral and drinking waters contain very high fluoride concentrations. It is a well known fact that drinking water exceeding the critical fluoride concentration (1 mg F−/L) may cause serious dental and skeletal damages. In this study, various techniques were evaluated to find the most suitable solution for defluoridation for these regions, which have high concentrations of fluoride in their water supplies. For this purpose, various chemical agents including locally produced alumina were investigated. Locally produced alumina gave promising and economically sound results in terms of defluoridation capacity and availability.


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