AWWA JAW49198

As part of the Information Collection Rule (ICR), the US Environmental Protection Agency (USEPA) has specified an immunofluorescence assay protocol for handling and reporting Giardia cyst and Cryptosporidium oocyst data. The protocol is flawed in several respects, primarily the extrapolation of cyst and oocyst counts in a small "equivalent sample volume" analyzed to a 100-L volume, the conversion of zero counts to less than one count, and the reporting of the data collected in this manner. Such data conversion and reporting can introduce data analysis problems. USEPA's draft method 1622 for analyzing water samples for Cryptosporidium does not specify how parasite count data should be treated or analyzed. If ICR method data handling and reporting specifications are followed, parasite concentration data obtained using method 1622 could also be inaccurate. The authors propose an alternative procedure for analyzing and reporting ICR parasite data. Includes 25 references, tables.

Product Details

Edition:

Vol. 91 - No. 3

Published:

03/01/1999

Number of Pages:

8

File Size:

1 file , 800 KB