Influence of Chlorination and the Distribution System on Mutagens in a Potable Water Supply

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.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Environmental Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Clark, Robert Raymond

• Environmental Sciences

Language dc:language

eng

Identifier

(UMI)AAI8203430

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/66906