AWWA WQTC65937

The objective of this powerpoint presentation was to evaluate the dependence of Cryptosporidiumoocyst and Giardia cyst removal on the influentconcentration of oocysts and cysts. The sampling approach included:Grab Sampling(10 L samples, concentrated to 200 mLwith CSCC);continuous sampling(CSCC hooked up directlyto filter effluent for 30 hourrun time); and,CSCC concentrated 288 Lof filter effluent to 200 mL. The analytical approach at Wisconsin StateLaboratory of Hygiene(WSLH) included:centrifugation;fluorescent antibodystaining; flow cytometry used toseparate microbes fromother particles in sample; and,separated microbes placedon slide and counted bymicroscopy. The analytical approach at Marshfield ClinicResearch Foundation(MCRF) included:membrane filtration;fluorescent antibodystaining; and,counting under a microscope. Potential implications include:water utilities using conventional surface watertreatment may not be achieving the level of oocystand cyst removal that they think they areachieving;when detected, typical counts in U.S. source waters areon the order of 100 microbes/L or less; and,extrapolation of Lake Mendota results to this levelsuggests removal may only be 0.5 log to 1.0 log, ratherthan 2.5 log to 3.0 log. Includes table.

Product Details

Edition:

Vol. - No.

Published:

11/01/2007

Number of Pages:

15

File Size:

1 file , 3.4 MB