Assessment of Methods for Detection of Infectious Cryptosporidium Oocysts and Giardia Cysts in Reclaimed Effluents
AUTOR(ES)
Quintero-Betancourt, W.
FONTE
American Society for Microbiology
RESUMO
This study evaluates the occurrence of Cryptosporidium oocysts and Giardia cysts in reclaimed effluents if method 1623 with the Envirochek capsule filters (standard and high-volume [HV] filters) and a modified version of the Information Collection Rule method (ICR) with the polypropylene yarn-wound cartridge filter are used. The recovery efficiency of the analytical methods was evaluated with samples of reagent, tap, and reclaimed water by using flow cytometer-sorted spike suspensions. (Oo)cyst recovery efficiency determined filter performance and method reproducibility in the water matrix tested. Method 1623 with the Envirochek HV capsule filter generated significantly higher recovery rates than did the standard Envirochek filter and the modified ICR method. Notwithstanding, large variations in recovery rates (>80%) occurred with samples of reclaimed water, and none of the water quality parameters analyzed in the reclaimed effluents could explain such variability. The highest concentrations of indigenous oocysts were detected by method 1623 with the HV filter, which provided a sufficient number of oocysts for further confirmation of infectious potential. Confirmation of species and potential infectivity for all positive protozoan samples was made by using a nested PCR restriction fragment polymorphism assay and the focus detection method most-probable-number assay, respectively. The methodology and results described in the present investigation provide useful information for the establishment of pathogen numeric standards for reclaimed effluents used for unrestricted irrigation.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=194950Documentos Relacionados
- Comparison of two methods for detection of Giardia cysts and Cryptosporidium oocysts in water.
- An evaluation of methods for the simultaneous detection of Cryptosporidium oocysts and Giardia cysts from water.
- Evaluation of the immunofluorescence procedure for detection of Giardia cysts and Cryptosporidium oocysts in water.
- Infectious Cryptosporidium parvum Oocysts in Final Reclaimed Effluent
- Modifications to United States Environmental Protection Agency Methods 1622 and 1623 for Detection of Cryptosporidium Oocysts and Giardia Cysts in Water