Despite new concerns by the U.S. Environmental Protection Agency that lead in drinking water may be more harmful than previously thought, Los Angeles area water agencies and the state Department of Health Services say that lead concentrations in California drinking water are practically non-detectable.
Currently, the amount of lead permissible in tap water is 50 parts per billion. The EPA said it is considering a new standard of 20 ppb. If the new standard is adopted, the EPA said, 38.1 million Americans would be drinking water exceeding the limit.
But the health threat appears to be most acute in the East in such cities as Boston, where lead pipes are still widely in service. Levels range from 2 ppb to 3 ppb in water delivered by the Los Angeles Department of Water & Power. The Metropolitan Water District, which wholesales water to municipal water agencies in Southern California, said there is no detectable lead in its water.
The problem--if there is one--comes after the water reaches the in-house plumbing or the service pipe between the water main and the house where tin-lead solder is used to link sections of pipe. Lead from the solder can leach into the water, especially if the plumbing is less than a year old.