Occurrence and separation of Cryptosporidium oocysts in drinking water treatment

2000 ◽  
Vol 41 (7) ◽  
pp. 159-163 ◽  
Author(s):  
P. Dolejš ◽  
O. Ditrich ◽  
T. Machula ◽  
N. Kalousková ◽  
G. Puzová

The presence of Cryptosporidium sp. in Czech drinking water sources was monitored. High numbers of Cryptosporidium oocysts were found in the Slezska Harta reservoir after 1997 summer floods. The influence of iron (III) coagulant dose, mixing conditions and preozonation on the removal efficiency of Cryptosporidium oocysts was studied. Low mixing intensity produced flocs with poor settling features. The efficiency of sedimentation expressed as residual iron after sedimentation was proportional to removal efficiency of oocysts. Both underdosing or overdosing of iron (III) coagulant resulted in decrease of COD, turbidity and oocyst removal. Preozonation positively influenced removal efficiency of oocysts in the conventional drinking water treatment train studied.

2009 ◽  
Vol 8 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Joe Brown ◽  
Mark D. Sobsey

Low-cost options for the treatment of drinking water at the household level are being explored by the Cambodian government and non-governmental organizations (NGOs) working in Cambodia, where many lack access to improved drinking water sources and diarrhoeal diseases are the most prevalent cause of death in children under 5 years of age. The ceramic water purifier (CWP), a locally produced, low-cost ceramic filter, is now being implemented by several NGOs, and an estimated 100,000 + households in the country now use them for drinking water treatment. Two candidate filters were tested for the reduction of bacterial and viral surrogates for waterborne pathogens using representative Cambodian drinking water sources (rainwater and surface water) spiked with Escherichia coli and bacteriophage MS2. Results indicate that filters were capable of reducing key microbes in the laboratory with mean reductions of E. coli of approximately 99% and mean reduction of bacteriophages of 90–99% over >600 litres throughput. Increased effectiveness was not observed in filters with an AgNO3 amendment. At under US$10 per filter, locally produced ceramic filters may be a promising option for drinking water treatment and safe storage at the household level.


2013 ◽  
Vol 47 (11) ◽  
pp. 3591-3599 ◽  
Author(s):  
Zhang Can ◽  
Liu Wenjun ◽  
Sun Wen ◽  
Zhang Minglu ◽  
Qian Lingjia ◽  
...  

2018 ◽  
Vol 156 ◽  
pp. 03038 ◽  
Author(s):  
Reni Desmiarti ◽  
Ariadi Hazmi ◽  
Primas Emeraldi ◽  
Munas Martynis ◽  
Yenni Trianda ◽  
...  

Inductively coupled plasma system was used in drinking water treatment system to kill the microorganisms in water such as total coliforms (TC), fecal coliforms (FC) and other coliforms (OC) from river water. The aim of this study was to investigate the effect of flowrate on removal efficiency (RE), death rate, and death yield and energy consumption of bacteria's. The frequency of the system was set at 4.6 MHz. The results show that the removal efficiencies and death rate of TC, FC and OC decreased with increasing flowrate. Compared to FC, the first-order reactions of TC and OC were lower in the following order: FC > OC > TC. The death yield of TC and OC significantly increased when the removal efficiency increased. The electromagnetic flux varied from 19.44 to 20.55 W/cm2 and the energy consumption was 0.26, 0.32, and 0.67 with flow rate at 20, 10 and 5 mL/minute, respectively. These results are very necessary to improve drinking water treatment.


2007 ◽  
Vol 5 (3) ◽  
pp. 367-374 ◽  
Author(s):  
Romulo E. Colindres ◽  
Seema Jain ◽  
Anna Bowen ◽  
Eric Mintz ◽  
Polyana Domond

Tropical Storm Jeanne struck Haiti in September 2004, causing widespread flooding which contaminated water sources, displaced thousands of families and killed approximately 2,800 people. Local leaders distributed PūR®, a flocculent-disinfectant product for household water treatment, to affected populations. We evaluated knowledge, attitudes, practices, and drinking water quality among a sample of PūR® recipients. We interviewed representatives of 100 households in three rural communities who received PūR® and PūR®-related education. Water sources were tested for fecal contamination and turbidity; stored household water was tested for residual chlorine. All households relied on untreated water sources (springs [66%], wells [15%], community taps [13%], and rivers [6%]). After distribution, PūR® was the most common in-home treatment method (58%) followed by chlorination (30%), plant-based flocculation (6%), boiling (5%), and filtration (1%). Seventy-eight percent of respondents correctly answered five questions about how to use PūR®; 81% reported PūR® easy to use; and 97% reported that PūR®-treated water appears, tastes, and smells better than untreated water. Although water sources tested appeared clear, fecal coliform bacteria were detected in all sources (range 1 – >200 cfu/100 ml). Chlorine was present in 10 (45%) of 22 stored drinking water samples in households using PūR®. PūR® was well-accepted and properly used in remote communities where local leaders helped with distribution and education. This highly effective water purification method can help protect disaster-affected communities from waterborne disease.


2018 ◽  
Vol 7 (3.3) ◽  
pp. 364
Author(s):  
Yootaek Kim ◽  
Taesung Chae

Artificial lakes constitute more than 40% of drinking water sources, and can be easily eutrophicated by accumulation of phosphor, nitrogen, and nutrition salts introduced by various industrial and domestic origins after 10–30 years of their construction. Specifically, the concentration of phosphor is considered as an important factor that influences eutrophication, and causes seven times the eutrophication of nitrogen. In the present study, porous ceramics were fabricated with bottom ashes (BA) from power plants for recycling purposes and illite, which is known to be an efficient absorption material for phosphor in water. The phosphor removal efficiency reached up to 59% when the composition rate of illite to BA was 4 to 6. The study indicates the possibility of developing phosphor absorbing porous ceramics by using spent materials such as BA as substitutes for expensive illite without a significant decrease in phosphor removal efficiency. 


2020 ◽  
Vol 1 (1) ◽  
pp. 10-19
Author(s):  
Emmy C. Kerich

Access to safe and clean drinking water is a major challenge to the people living around Ahero Irrigation Scheme (AIS). Water sources in the area are constantly and increasingly polluted by agrochemical like pesticides from rice farming. 2, 4-Dichlorophenoxyacetic acid (2,4-D) is an herbicide extensively used in AIS. The neurotoxic, immunosuppressive, cytotoxic and hepatoxic effects of (2,4-D) have been well documented. Residues of (2,4-D) have been documented in ponds, rivers, lakes and irrigation canals. Therefore this study surveyed agrochemicals used in AIS, the drinking water source for the residents and finally water treatment option for the obtained water in the year 2013. The study established that (52.8%) of the farmers used hand-weeding and 20.8% of them use (2,4-D) for the weeds control. Results indicated that the most preferred water source was lined improved well (47.2%) followed by irrigation canal (22.2%), the least preferred was rain water with (2.8%). The most used method of water treatment was chlorination (45.8%). Spearman’s coefficient of correlation ( ) revealed that there was positive correlation between the two variables ( =0.145, 72, p=0.224>0.05). As  is positive, it implies that the type of treatment given to water depend on its source of the water. Despite the use of chlorinate with almost half of the residents, some of them (22.2%) do not treat their water at all, which may pose a risk of getting water related diseases. Furthermore, despite a proportional number of residents obtaining their water from irrigation canal, all of them do not have appropriate method/s for treating water contaminated with organic pollutants such as herbicides. There is a need to promote water appropriate drinking water treatment method/s in the study area to prevent water related diseases at the family level. Doi: 10.28991/HEF-2020-01-01-02 Full Text: PDF


2001 ◽  
Vol 43 (12) ◽  
pp. 225-228 ◽  
Author(s):  
K. Lahti ◽  
J. Rapala ◽  
A-L. Kivimäki ◽  
J. Kukkonen ◽  
M. Niemelä ◽  
...  

Problems caused by cyanobacteria are common around the world and also in raw water sources of drinking water treatment plants. Strains belonging to genera Microcystis, Anabaena and Planktothrix produce potent hepatotoxins, the microcystins. Laboratory and pilot scale studies have shown that microcystins dissolved in water may pass the conventional surface water treatment processes. In 1998 the World Health Organization proposed a guide value of 1 μg/L for microcystin-LR (MC-LR) in drinking water. The purpose of this research was to study the occurrence of microcystins in raw water sources of surface waterworks and in bank filtration plants and to evaluate the removal of microcystins in operating waterworks. Four bank filtration plants and nine surface waterworks using different processes for water treatment were monitored. Phytoplankton was identified and quantified, and microcystins analysed with sensitive immunoassay. Microcystin occurrence in selected water samples was verified with HPLC and a protein phosphatase inhibition method. Microcystins were detected sporadically in raw water sources of most of the waterworks. In two raw water supplies toxins were detected for several months. The highest microcystin concentrations in incoming raw water were approximately 10 μg/L MC-LR equivalents. In treated drinking water microcystins were detected occasionally but the concentrations were always below the guide value proposed by WHO.


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