AWWA WQTC50360

Since Cryptosporidium has been found to cause disease in humans there has been increased public concern over its presence in public drinking water supplies. In an effort to identify methods which could provide more accurate and lower detection levels in less time, samples were analyzed using the standard ICR method and the HACH IMS method. The IMS method did not prove to be a panacea; recovery and detection limits varied by both analysis method and sample type. Water samples were collected from seven different local sites: well water, conventional WTP settled water, WTP filter backwash; WTP sludge recycle stream, run-off from a cattle grazing site, a flood control canal, and a natural spring known to be under the influence of surface water. Samples were collected and filtered through a spiral-wound cartridge filter in the field. Elution methods were the same for both the ICR method and immunomagnetic separation. The filter was placed onto a stainless steel pan and was cut away from the core. The filter fibers were separated, placed into stomacher bags and homogenized. Eluting solution (1.75 L) was added to the fibers and the bags were again placed into the stomacher. The process was then repeated using 1.0L eluting solution. The resulting eluted particulate suspension was centrifuged at 1,050 x g for 10 minutes. The sample eluant level was aspirated down to a pellet plus 5 mL of overlying eluting solution. The pellet was resuspended in its solution by vortexing. Bottle particulates were combined and re-centrifuged until all were concentrated into one conical bottle. Includes 2 references, tables.

Product Details

Edition:

Vol. - No.

Published:

01/01/1999

File Size:

1 file , 480 KB