Main Title |
Protozoan Sources of Spontaneous Coliform Occurrence in Chlorinated Drinking Water. |
Author |
Shotts, E. B. ;
Wooley, R. E. ;
|
CORP Author |
Georgia Univ., Athens. Coll. of Veterinary Medicine.;Environmental Protection Agency, Cincinnati, OH. Risk Reduction Engineering Lab. |
Publisher |
May 89 |
Year Published |
1989 |
Report Number |
EPA/600/2-89/019; |
Stock Number |
PB89-190292 |
Additional Subjects |
Coliform bacteria ;
Protozoa ;
Chlorination ;
Water treatment ;
Interactions ;
Tolerances(Physiology) ;
Survival ;
Drinking water ;
Sources ;
Water distribution ;
Distribution systems ;
Reservoirs ;
Bacteria ;
Exposure ;
Bioassay ;
Dosage ;
Water borne diseases
|
Holdings |
Library |
Call Number |
Additional Info |
Location |
Last Modified |
Checkout Status |
NTIS |
PB89-190292 |
Some EPA libraries have a fiche copy filed under the call number shown. |
|
07/26/2022 |
|
Collation |
41p |
Abstract |
The spontaneous occurrence of coliforms in chlorinated drinking waters has resulted in concern over their potential source and mechanism(s) of introduction into water delivery systems. Previous observations related to protozoal resistance to chlorine coupled with the ingestion of bacteria by this group of organisms prompted an in-depth study of bacterium-protozoan interaction in the presence of chlorination. Bacteria used were either from previous 'spontaneous coliform outbreaks' or potential human pathogens. The protozoans utilized were laboratory adapted and wild strains of protozoans found naturally in water reservoirs. These organisms were established in axenic cocultures and the effect of various concentrations of chlorination and exposure were determined. It was found that, alone, the bacteria were killed by from 0.25-1 mg/L of chlorine; however, when ingested by protozoans, these same bacteria survived in significant concentration levels of chlorination 4 to 10 times the above dose. It further suggests a need for increased awareness in developing improved methods of treating reservoir waters. |