AWWA ACE68896

This powerpoint presentation begins by presenting a brief overview of disinfection byproducts (DBPs) as emerging contaminants. Research objectives are listed and include the following:obtain samples (~50 mg) of synthesized, analyticalgrade DBPs from the U.S. Environmental Protection Agency (USEPA);analyze the direct-acting cytotoxicity and genomicgenotoxicity of the individual DBPs with Chinesehamster ovary (CHO) cells;determine the cytotoxic and genotoxic rank order ofthe DBPs; and,develop a quantitative and comparative DBP toxicitydatabase. Presentation conclusions indicate the following: with our current database, ~70 DBPs werecompared on a level toxicological playing field;we can quantitatively compare the cytotoxicity ofDBPs using their %C1/2 values;we can quantitatively compare the genotoxicity ofDBPs using the SCGE Genotoxic Potency values;we can compare classes or specific groups ofDBPs based on their Toxicity Index, within aclass, the reciprocal of the averaged median %C1/2 values is the cytotoxicity index value and thereciprocal of the averaged median genotoxicpotency values is the genotoxicity index value; the current USEPA-regulated DBP classes(THMs and HAAs) are substantially less toxicthan emerging DBPs;iodinated-DBPs are far more toxic than theirbrominated and chlorinated analogs;N-DBPs are much more toxic than C-DBPs;the occurrence of these emerging DBPs are onthe rise because of changes in source waterquality and the increased use of alternativewater disinfectants; and,these emerging DBPs may pose adverse healthrisks. Includes figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2008

Number of Pages:

30

File Size:

1 file , 1.2 MB