|
In D.C., they switched to a new, stronger, treatment for the water to deal with an intermittent problem with microorganisms in the water. That new treatment was a little more corrosive and caused lead to leach out of solder joints and even the relatively few old lead supply lines that were still in use. A few homes had somthing like 10,000 time the legal level for lead in the water. Those older homes had lead supply pipes that went from the water main to their house.
I forget the numbers, but I think there were several thousand houses in the DC area that still have lead supply pipes. In many cases, the homeowners had no idea.
Filters reduce the lead by something like 99%. If you are 10,000 times over the legal limit of lead, and your filter reduces that by 99%, then your filtered water will be 100 times the legal limit.
|