The element Lead is what was used in most early plumbing systems before switching over to brass, copper, galvanized, black iron, and cast iron. As lead water pipes deteriorates, the parts per million particles rise above an acceptable level. Children are more susceptible to a build up of heavy metals in the blood. Lead causes all sorts of problems in the human body, especially the brain. When the water supply system in Flint, Michigan was switched back the original water mains, it flushed and disturbed all of the lead particles right into the drinking water, (domestic supply ).
As sections of the Water Main system gets replaced throughout NYC, existing water services are being replaced. If those water services are made of lead,, the process of draining and recharging the water lines will flush lead particles right into the drinking water.
