Yes. We are dealing an ancient problem. Lead, a malleable and inexpensive metal, has been used for water pipes since the Roman period. It’s been known since then that toxic amounts of lead from these pipes could be released into soft water. This can occur because lead can be dissolved by weak acids found in many water supplies.
The solution was well known, either the lead pipes had to be removed or water quality had to be changed. Replacing the pipes can be very costly, especially if their locations are no longer known, so adding lime and other corrosion inhibitors to community water has often been used as a remedy.
Even with these known problems, it was only a few decades ago that plumbing codes were changed to require water pipes be made of materials other than lead. So today, a substantial number of service lines, distribution lines, and household water pipes in American communities are made of lead.
Flint is by far not the first community where lead poisoning has emerged as a “new” problem. Fifteen years ago, Washington, D.C. changed the disinfection chemical for the municipal water supply from chlorine to chloramine, which caused lead to leach from the water pipes, and the problem was not corrected until three years later. More recently, similar problems have occurred both in North Carolina and in Maine. In all of these cases, the problems could have been foreseen, but decisions on water treatment were primarily made based on considerations of cost and feasibility. Last week it was reported that tap water in Sebring, Ohio had elevated levels of lead. It’s just another example that ancient water pipes made from lead will continue to cause problems.
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