Lead in Drinking Water

Lead was my favorite metal when I was a boy growing up in a boarding school in the Belgian Congo. We boys would melt down the lead plates out of old car batteries. We melted the lead in cans over wood fires and then poured out the silvery metal on the cement floor or into a bamboo segment to mold it. It was so shiny and so heavy and we had a way of using it to explode match heads like fire crackers.

It was only decades later that I discovered that lead could be found in drinking water and that it was toxic particularly for children under six.

Question #1: What is lead?

Lead is a soft, gray metal that is used in a variety of ways. It was used extensively for print type setting. It was also used extensively in plumbing both for making lead pipes and for soldering before it was banned by law in 1987.

Before 1960, paint used inside houses commonly contained lead until it was discovered that paint chips in water or paint dust inhaled were both very toxic.

Lead is still used in making fishing weights and in making car batteries.

Question #2: How does lead get into our drinking water?

Houses built before 1940 often used lead pipes in home plumbing. The service lines bringing water to individual homes were often made of lead. This resulted in high levels of lead in drinking water. Even up until 1987, lead solder was used to seal the joints of copper pipes and lead leaked into drinking water from this solder.

Even today, brass fixtures and faucets can contain up to 8% lead. This is still a significant source of lead in drinking water. This is particularly true when hot water is used.

The level of lead in drinking water increases the longer the water sits in pipes without being used. If it sits 6 hours or longer, more lead leaks into the water. Also, acidity in water will corrode or dissolve lead in the plumbing more rapidly.

Question #3: How can lead affect my health?

The degree of harm lead does to your health depends on how much lead has built up in your body over the years. It also depends on one's age.

When lead is taken into the digestive system either in water or in food, it is distributed throughout the body by the circulatory system. It builds up mostly in your bones. Some lead remains in your blood. It is because of this fact that the amount of lead measured in your blood can be used to estimate the total amount of lead in your body.

Children between the ages of two and six are particularly vulnerable to lead. Too much lead in a child's system can cause learning problems. It can cause delay in physical and mental development. It can cause both brain damage and kidney damage.

Adults who drink water with too much lead, over a period of years, can experience an increase of blood pressure and kidney damage.

To put things in perspective, however, it is helpful to note that the Environmental Protection Agency (EPA) estimates that the main sources of lead exposure are through ingesting paint chips and inhaling paint dust. They estimate that only 10 to 20% of our exposure to lead comes from lead in drinking water.

Question #4: How big a problem is lead in our drinking water?

This depends on a number of factors. You need to check the level of lead in your local water supply, but even more important is the age of your house and whether or not lead piping or solder was used in your house's plumbing. Then too, theres the question of paint. Was lead based paint used in your house?

One example will suffice to show the importance of vigilance. As recent as 2003, it was discovered that thousands of residents in Washington D.C. had dangerous levels of lead in their tap water. Two-thirds of the 6,000 households tested were found to have water that tested above the hazard level of 15 parts per billion (ppb). There were 157 homes with levels above 300 ppb! If this could happen in our nations capital, how can we be sure it won't happen in our own towns?

Question #5: How can I know if lead is in my drinking water?

If you get your tap water from a public water system, they are required by law to send you annually a Consumer Confidence Report (CCR). You can also find information on contaminants that were above the Maximum Contaminant Level (MCL) on the Environmental Protection Association (EPA)website. Look to see if there is lead in your water and how much. They cite the "Level Found" and the "MCL" (Maximum Contaminant Level). For lead, the standard set by the EPA is .015 milligrams per liter. Any water which has more than this amount of lead is not safe. The water company is required to state in the CCR if lead is over the MCL limit and what they are doing to correct it. They are also required to inform the public through newspapers and television that the level of lead is over the level of safety.

If you get your tap water from a private well, it is recommended that you have it tested for lead and other pollutants that may make it unsafe to drink as is. You can order a water testing kit and test it yourself, or hire a water testing laboratory in your area to do it for you. Because much lead pollution actually comes from home plumbing and from the water delivery system, the only way to really know the actual level of lead in you tap water is to test it yourself or have it tested by a laboratory for you.

Question #6: How would I go about removing lead from my drinking water?

There are several simple precautions you can take to reduce the level of lead in your tap water. For one, don't use hot tap water in your cooking since hot water tends to bring more lead out of the plumbing. Secondly, if your water has sat in your pipes without being used for move than 6 hours, let it run until the cold water from outside your house is coming through your tap. This will flush out lead that has seeped from your plumbing into the water sitting in your pipes.

There are three kinds of filters that can remove lead in water from your tap water: Distillation, Reverse Osmosis, and Filtration (granular or carbon block). However, you need to check the individual filter that you are considering to not only see if they claim to reduce lead, but to verify that it has been certified by the NSF International as a filter that does indeed effectively reduce lead.

For further information on the best filters in the categories of Distillation, Reverse Osmosis and Filtration go to "Best Water Filters". Or for a broader discussion of the multiple considerations you need to keep in mind in selecting a filter, go to "How to Choose a Water Filter".

For more information about lead and other toxic contaminants, go to "Lead in Drinking Water".

SUMMARY TABLE