Montebello Forebay, Los Angeles County, California (Nellor et al.,1984)

Disinfected filtered secondary effluent, storm runoff, and imported river water used for replenishment; also, recovered ground water

Toxicology testing: Ames Salmonella test and mammalian cell transformation assay. 10,000 to 20,000x organic concentrates used in Ames test, mammalian cell transformation assays, and subsequent chemical identification. The level of mutagenic activity (in decreasing order) was storm runoff > dry weather runoff > reclaimed water > ground water > imported water. No relation was observed between percent reclaimed water in wells and observed mutagenicity of residues isolated from wells

Epidemiology: In the geographical comparison study, the population ingesting recovered water did not demonstrate any measurable adverse health effects. The household survey (women) found no elevated levels of specific illnesses or other differences in measures of general health

Denver Potable Water Reuse Demonstration Project (Lauer et al., 1990)

Advanced wastewater treatment (AWT) effluent (with ultrafiltration or reverse osmosis) and finished drinking water (current supply)

Toxicologic testing: 150 to 500x organic residue concentrates used in 2-year in vivo chronic/carcinogenicity study in rats and mice and reproductive/teratology study in rats. No treatment-related effects observed