Metals in drinking water from new housing estates in the Sydney area

Metals in drinking water were measured in 95 new houses less than 18 months old in the Sydney metropolitan area. Three samples (first-flush, post-first-flush, and fully flushed water) were collected from each house, and "control" samples from the five Sydney Water points that supplied the houses, a total of 326 samples. They were analyzed for Pb, Cu, Mn, Zn, Cd, and Al. At the supply points, the levels of all metals were at or below Australian Drinking Water Guidelines (ADWG). In the houses, metal levels varied. Of the first-flush samples, Pb was above ADWG in 60% and above US EPA Guidelines in 81%, Cu was above ADWG in 12%, and Cd was above ADWG in 4%. Of the post-first-flush samples, Pb was above ADWG in 24%, Cu was above ADWG in 18%, Cd was above ADWG in 1%, and Zn was above ADWG in 1%. The other metal contaminants (Mn and Al) were within ADWG. In fully flushed water, the levels of all metals were well below ADWG.