The horrific stories about lead in the drinking water in Flint, MI understandably have people around the world worried about the potential of lead being in their drinking water. So let’s talk about lead, starting with the Romans.
The symbol for lead on the periodic table is Pb, which stands for Plumbus, which is Latin for lead. Incidentally, that is the source of the word “plumber.” So plumbing has always been connected to lead.
The reason for the concern is lead is very toxic. It can cause a myriad of physical and mental problems, including brain damage and lessening of development among children…even in small doses. Lead poisoning can be fatal.
There are two types of lead. The first is organic lead, which can be absorbed through the skin via fumes, etc. Leaded gas contained organic lead. Not only could the fumes be absorbed, they could also settle in dirt, etc., where the lead could be ingested by children. Unleaded gas is banned in the United States, but not entirely throughout the world.
Then there is inorganic lead which cannot be absorbed, but can be ingested. A prime example of that is lead-based paint. Lead-based paint has a certain sweetness to it, which is one reason children will eat it. Lead-based paint is extremely lethal, which is why it is rarely used in homes anymore.
Which gets us to the drinking water. The water we drink is treated and tested daily at water filtration plants before it is sent on the way to our homes. The concern is…what happens from the time the water leaves the filtration plant to the time it comes out of our faucets.
There are three potential issues. The first is if the water service pipe between the city water main and your house is made of lead. Lead oxidizes quickly, and can leach into the water. One way water is treated is to include anti-corrosive agents to limit the potential of lead leaching into the water once it leaves the plant. This was not done in Flint, which caused the lead to leach. While it is done in our area, it is not foolproof.
The second way lead can leach into the water is through the solder that connects the copper water piping inside the house. Years ago the solder contained anywhere from 50% to 95% lead. The solder used by plumbers since 1986 has been lead free. Lead can leach from lead-based solder into your drinking water.
The third way is from valves and fixtures in the home which are made of brass. The brass alloy used in the manufacture of these products has always contained a small amount of lead. Changes in the law made the use of lead in brass illegal a few years ago.
So what can you do to reduce the risk? Three things.
- Before you pour a glass of water, run water in your sink for a few minutes. That would cause any lead that may be sitting there to go down the drain.
- If you are in an older home, consider getting lead-free valves and fixtures.
- The best bet is to install a point-of-use water filter. These are specifically designed to filter out lead and other potentially dangerous agents. Next month we will discuss point-of-use filters.
If you want more information, here is a really good site that talks about lead.