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Reducing Lead Levels in Drinking Water
This article outlines issues involved with lead in drinking water, including the Causes of Lead Contamination, the New EPA Lead Standards, and In-Home Water Treatment Units that have been proven to reduce lead levels.
------------------------------------ Lead exposure is a major health concern that is gaining recognition across the country. Magazines, newspapers, television, and radio have been spreading the word about its risks, and although only 20 percent of lead exposure is caused by drinking water, the nation has recently focused its attention there.
And there is just reason for concern. The U.S. Environmental Protection Agency (EPA) calls lead "a highly toxic metal the agency considers a major public health threat."
Although in adults lead can increase blood pressure and interfere with hearing, children are at a greater health risk due to lead ingestion than adults. In children, lead can interfere with the formation of red blood cells, delay physical and mental development, and impair mental abilities. At high levels of exposure, lead can cause anemia, kidney damage, and mental retardation.
Pregnant women should also be especially cautious about lead exposure, as it can cause premature birth, and reduce the birth weight of babies. The good news is that it is possible to reduce lead levels in drinking water for several reasons:
- Determining which homes are likely to have high lead levels in drinking water is relatively easy;
- The EPA recently set stricter regulatory standards for lead;
- Several in-home water treatment technologies that reduce lead are available to consumers.
In fact, the national Centers for Disease Control considers lead to be the country's number one preventable pediatric health problem.
Causes of Lead Contamination
The greatest contributions to childhood exposure to lead are lead-based paint, urban soil and dust, and drinking water.Lead rarely occurs naturally in drinking water. Instead, lead contamination usually occurs at some point in the water delivery system. It is most commonly caused by the corrosion of lead service connections, pipes, or lead solder used to join copper pipes in the home. Homes that are less than 10 years old and have lead solder or homes that are connected to the water main by a lead service line are more likely to have higher levels of lead in the water, according to the EPA.
In 1986, lead was banned from use in pipes and solder in public water systems. It was also banned in household plumbing and limited in brass fixtures. Although illegal use of solder does continue, the EPA is considering further restrictions on the sale or manufacture of lead solder and brass fixtures that contain lead.
Water is known as the universal solvent. As it travels, it picks up traces of most things in its path, which often includes calcium and magnesium, the two minerals that cause what is commonly referred to as "hardness" in water. Hardness is usually measured in grains per gallon (gpg). The greater the grains per gallon, the greater the water hardness.
Hard water has many disadvantages. It tends to clog pipes, damage kitchen and bath fixtures and appliances, leaves a film on bathtubs and shower tiles, and does not rinse well from skin when showering. For these reasons and others, many consumers choose to install a water softener in their home. The most common type of softener uses cation exchange. In this process, the softener exchanges the hard calcium and magnesium ions for neutral sodium ions, thus reducing the hardness of the water.
Lead levels may be increased in homes that have naturally soft water. It is important, however, to make the distinction between a naturally soft water and softened water from a water softening device. Lead in drinking water is most commonly caused by the corrosion of lead plumbing materials. Water varies in its characteristics, and some wa
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Sat, Jul 31, 2010
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Water Quality Association
International Headquarters & Laboratory
4151 Naperville Road
Lisle, IL 60532-3696
USA
630 505 0160, Fax 630 505 9637
info@wqa.org, www.wqa.org
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