Detection of giardia and cryptosporidium in marine waters

1995 ◽  
Vol 31 (5-6) ◽  
pp. 439-442 ◽  
Author(s):  
D. C. Johnson ◽  
K. A. Reynolds ◽  
C. P. Gerba ◽  
I. L. Pepper ◽  
J. B. Rose

Raw sewage disposal in marine waters is a common practice in many countries. This practice raises health risk concerns of possible transmission of Giardia and Cryptosporidium. Both of these protozoa have been shown to be transmitted by recreational swimming. To date no studies have determined the efficiency of their detection and concentration in marine waters. This study evaluated the efficiency of their detection in tap water and from marine waters in Hawaii with two different filter types. This study compared a polypropylene fiber cartridge filter, DPPPY (1.0 μm nominal porosity) (Cuno, Meriden, CT) which is typically used for parasite detection and the Filterite negatively charged filter (0.45μm) (Filtemp Sales, Inc., Phoenix, AZ). The latter would allow for both viruses and parasites to be concentrated simultaneously. The organisms were removed from the filter by passing the eluent through the filters in the opposite direction of collection and detected by indirect immunofluorescence antibody staining specific for Giardia and Cryptosporidium. Processing was simpler and faster with the Filterite filter and the overall efficiency for both Giardia and Cryptosporidium detection was greater. These methods are currently being used for the detection of the oocysts and cysts at bathing beaches in Hawaii impacted by marine sewage discharge.

Risk Analysis ◽  
1990 ◽  
Vol 10 (4) ◽  
pp. 581-585 ◽  
Author(s):  
Wan K. Jo ◽  
Clifford P. Weisel ◽  
Paul J. Lioy
Keyword(s):  

2019 ◽  
Vol 70 (7) ◽  
pp. 2579-2583 ◽  
Author(s):  
Sampah Georges Eblin ◽  
Kouakou Seraphin Konan ◽  
Oi Mangoua Jules Mangoua ◽  
Valentin Nedeff ◽  
Andrei Victor Sandu ◽  
...  

Doubt about the quality of tap water, due to its color, taste and unpleasant odors, forces a large part of the population of the city of Daloa (west-central of Cote d�Ivoire) to turn to spring and traditional wells waters whose quality is unknown. This study aims to assess the level of nitrate pollution of these shallow aquifers through 29 points including 9 spring and 20 traditional wells spread all over the city. Nitrate concentrations range from 2.5 mg/L to 301.1 mg/L, with 30% of the wells containing an excess of nitrate, beyond the WHO drinking standard (50 mg/L). The map of levels of nitrate concentrations in the city�s wells and springs shows the exposure of the populations of the old downtown neighborhoods to a high health risk due to the high pollution potential of nitrate in the water.


Author(s):  
Mª Concepción Almonacid Garrido ◽  
Pilar Jiménez Navarro ◽  
Javier Peinador Asensio ◽  
Mª José Villanueva Suárez ◽  
Mª Dolores Tenorio Sanz

2000 ◽  
Vol 41 (7) ◽  
pp. 189-196 ◽  
Author(s):  
K. Guyot ◽  
M. F. Gireaudot-Liepmann ◽  
A. Cabon ◽  
I. Riveau-Ricard ◽  
M. Lange ◽  
...  

Viable Cryptosporidium parvum oocysts were processed by the US EPA 1622 method to determine if the procedure that requires successive filtration, elutionand centrifugation alters their integrity and viability (determined by in vitro excystation). Oocyst seeded in tap water samples were also used to evaluate recovery efficiencies and impact of the whole procedure on oocyst viability. Filtration through Envirochek Gelman cartridge was found not to damage oocysts. The use of Laureth-12 buffer during the elution step was shown to lead to greater spontaneous oocysts excystation than other phosphate buffers containing between 80 and/or SDS (like the Gelman buffer). However, this drawback was widely balanced against the best efficiency of this buffer to elute oocysts captured by the cartridge filter and therefore against its high recovery efficiency. Thus, in water samples in which the oocyst concentration is expected to be low, it is more advantageous to employ the Laureth-12 buffer for the elution through it can influence viability. Centrifugation speeds (1,000–5,000 g) did not alter oocysts.


2015 ◽  
Vol 74 (11) ◽  
Author(s):  
Tuqa Haitham Khattab ◽  
Nabsiah Abdul Wahid

The state of Penang has been known to be offering the lowest water tariff rate for its users in Malaysia. The most recent water services reform exercise in Malaysia saw a suggestion made for the abolishment of water subsidies by the federal government and for full cost recovery (FCR) approach to be applied. This means that the operating cost will be transferred to consumers instead. This study reports a descriptive pilot study results that explored Penang user’s responses to various issues pertaining to their perception of water quality, health risk concern and willingness to pay for increased water tariff. The findings show that users were not that happy with water quality only in terms of taste, suspended solids that should not have come out from the tap but sometimes they do, and chlorine content; however, not for its odor or color. As for health risk concern, although majority believe that their tap water adhered to the drinking standard set by World Health Organization (WHO), still many perceived that their tap water is associated with health risk and unsafe for drinking, which saw many opted to buy bottled water for their drinking consumption. As for willingness to pay, majority think that the tariff should not be increased at all, particularly at the current water quality provided to users. Gender and monthly income as part of demographic factor play important roles in enhancing the study’s outcome.  The findings provide preliminary insight to how water users may act towards a possible water tariff increase in the state.


2013 ◽  
Vol 121 (7) ◽  
pp. 839-846 ◽  
Author(s):  
Ho Wing Leung ◽  
Ling Jin ◽  
Si Wei ◽  
Mirabelle Mei Po Tsui ◽  
Bingsheng Zhou ◽  
...  

2013 ◽  
Vol 185 (9) ◽  
pp. 7675-7691 ◽  
Author(s):  
Jin Lee ◽  
Eun-Sook Kim ◽  
Bang-Sik Roh ◽  
Seog-Won Eom ◽  
Kyung-Duk Zoh

Harmful Algae ◽  
2017 ◽  
Vol 61 ◽  
pp. 31-45 ◽  
Author(s):  
Ellen P. Preece ◽  
F. Joan Hardy ◽  
Barry C. Moore ◽  
Michael Bryan

Biofilms ◽  
2005 ◽  
Vol 2 (2) ◽  
pp. 105-117 ◽  
Author(s):  
S. Skraber ◽  
J. Schijven ◽  
C. Gantzer ◽  
A. M. de Roda Husman

Biofilms in drinking-water distribution systems may accumulate human pathogenic viruses. Viruses that attach to biofilm are removed from the water phase improving the water quality. However, if released in slough, it may still present a risk of infection. This review describes the available data on the presence of pathogenic viruses in drinking-water biofilms. First, biofilms of distribution systems potentially contribute to viral contamination of tap water only if infectious viruses are present initially in the water, which has been shown in several recent studies. However, only one out of three field studies showed the presence of infectious enteroviruses in natural biofilms from drinking-water networks. The presence of pathogenic viruses in biofilms points to the ability of these viruses to attach to biofilms. This has also been shown in pilot-scale studies in which bacteriophages and vaccine poliovirus strains were spiked into water and could be eluted from artificial biofilms. Reported attachment rates vary greatly and may depend on many factors such as the biofilm characteristics, the virus strain and the efficiency of viral recovery from biofilms. One study reported biphasic viral inactivation in biofilms with rapid initial inactivation followed by slow inactivation, implying that some of the attached viruses are able to remain infectious for a longer time. In several laboratory experiments, virus attachment to biofilms has been reported under various conditions; however, although detachment of sloughs in distribution systems has been observed, the presence of viruses in these sloughs was not studied. Here, we discuss the possible presence of infectious pathogenic viruses in sloughs; the extent to which these will pose a health risk remains to be investigated.


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