AWWA WQTC71564

This powerpoint presentation presents the fate of chlorinated disinfection byproducts (DBPs) indoors based on arobust database. Data for DBP fate was generated through three-year field and experimental studies conducted ondrinking water originating from various distribution systems in the Quebec City region of Canada. The data comprisesfield studies conducted under "real conditions" in various residences to evaluate DBP fate following heating, boiling, point-of-use(POU) filtering and refrigeration, as well as the effect of daytime and night-time stagnation of water in cold water pipesand hot water tanks. Experimental studies conducted in controlled conditions focused on water filtered by POUdevices and stagnation in copper and plastic plumbing. Both field and experimental studies were repeated to obtainmonthly patterns of DBP fate indoors. Results demonstrated that all types of manipulation of water have effects onchlorinated DBPs: boiling and refrigerating have a considerable impact on trihalomethanes (THMs), but not on haloacetic acids (HAAs); POU filteringaffects both THMs and HAAs significantly, but the effects change according to the "age" of the filter; THM levelsincrease much more than HAAs when cold water stagnates for various hours in the plumbing; stagnation in plastic pipeshas less impact on chlorinated DBPs than stagnation in copper pipes; copper release during stagnation of cold water ishigh and can be associated with DBP fate; and, transit in the hot water tank has a huge impact on both THM and HAAlevels, much more so than the impact of long stagnation of cold water in the plumbing. The presentation also discussesthe variability of DBP fate according to the type of "reference water" (municipal distribution system), specific THM andHAAs species (brominated and non-brominated) and seasonal conditions (i.e. the initial temperature and water quality of"reference water"). The implications concerning public health protection and exposure assessment in epidemiologicalstudies are also discussed, and specific recommendations are presented for handling tap water indoors to reduceDBP exposure in tap water. Includes figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2009

Number of Pages:

34

File Size:

1 file , 1.6 MB