Files in this item
|(no description provided)|
|Title:||Influence of Chlorination and the Distribution System on Mutagens in a Potable Water Supply|
|Author(s):||Clark, Robert Raymond|
|Department / Program:||Civil Engineering|
|Degree Granting Institution:||University of Illinois at Urbana-Champaign|
|Abstract:||Mutagens were recovered from a Central Illinois potable water supply by adsorption on polyurethane foam plugs. Assay of these concentrates with the Ames Salmonella/microsome reversion assay showed both promutagenic and direct-acting responses in TA98. Examination of the water at the groundwater source, following treatment and after passage through the distribution system, revealed that the level of both direct and activatable mutagenicity increased within the distribution system. The utility studied uses a groundwater source that contains ammonia and methane. To control taste and odor problems the utility alternates disinfection practice from chloramine to chlorination beyond breakpoint at monthly intervals in the summer. We assayed the mutagenicity of the water at weekly intervals and continually through transitions from chloramine to breakpoint and reverse for a period of a year. In general chloramine disinfection produced water with more S-9-dependent than direct-acting mutagenicity. Chlorination beyond breakpoint reversed this order. Detailed examination of the appearance of mutagen and chlorine at the tap showed patterns consistent with the formation of mutagen by reaction of disinfectant with substances in the water, possibly contributed by the distribution system.
Several fire hydrants located on dead ends in the distribution system were flushed and the water collected and extracted. These samples had high amounts of promutagenic activity which was filterable and hence associated with the particulate matter in the water. One of the most potent of these extracts was fractionated by high pressure liquid chromatography. Two known mutagens, benzo(a)pyrene and benz(a)anthracene, were identified in the extract.
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1981.
|Date Available in IDEALS:||2014-12-13|
This item appears in the following Collection(s)
Dissertations and Theses - Civil and Environmental Engineering
Graduate Dissertations and Theses at Illinois
Graduate Theses and Dissertations at Illinois