How does lead get into my tap water? Lead gets into drinking water if there are old plumbing systems and/or water distribution systems that have been made with lead soldering. As seen in the picture, the small parts that connect pipes were made with lead. Water can absorb the toxic lead by passing through these parts. Hot water erodes even more of the lead than cold water. Although lead soldering was made illegal in this country in 1986, older homes will still have these parts on their pipes.
How dangerous is lead in my tap water? Drinking water is not considered a primary cause of lead poisoning, but it is certainly a source of exposure that can contribute to high blood lead levels, especially among young children. According to the book Getting the Lead Out (1997) by Irene Kessel and John T. O'Conner, "Drinking water contributes to about 20% of lead exposure for an average 2-year-old, and from 5 to 50% for children generally (p. 157)." This may seem like a small contribution to the lead hazard problem, but it can be extremely dangerous if used for baby formula, as the book goes on to say. "The most alarming occurrence of drinking water causing severe lead poisoning is that of infant fed formula made with lead-contaminated tap water, in which case the water can account for 85% of lead exposure, and can result in severe lead poisoning (p. 157)."
What are some sources of water contamination? There are many different factors taken into account when determining if a water source is contaminated with dangerous amounts of lead. Here is a list of some of those factors:
1) The "aggressiveness," or "corrosiveness" of water. This refers to how "soft or hard" the water is, or in other words, how acidic the water is. If the water has a high acidity, it is more likely to eat away at the pipes and therefore be contaminated with a higher amount of lead than less acidic water. "Soft" water actually dissolves more lead whereas hard water can line the pipes and prevent as much lead from leaching into the water.
2) Pipes. Lead pipes are most dangerous in homes that were built before 1920. However, in any pipes where water sits for a while it is a potential hazard because lead can leach slowly into the water.
3) Fixtures. Brass faucets or other fixtures used around your source of water could be leaching lead into the water.
4) School drinking fountains. The drinking fountains in elementary schools across the country have been tested and some have been found to contain high levels of lead. Kessel and O'Conner report in their book that "In 1988 the EPA found that the water from some drinking fountains had lead levels up to 20,000 ppb, 400 times the then-existing maximum level considered safe [...] Federal law mandates the states to correct the situation [...] If you have children in school, check to see if your town has tested for lead in drinking fountains (p. 160)."
5) Antique kettles. Some antique kettles may have been made with lead solder and will contaminate tea or water boiled in them because heat concentrates the effects lead.
How can I tell if my water is contaminated? Have your water tested!! That is the ONLY WAY TO KNOW FOR SURE! When someone comes to do the water test, there should be three water samples taken, the first ("first-draw" sample) in the morning during the first time the water is turned on, a second (a "flush sample") after the water has been running for about 5 minutes, the third test will be a repeat of the second test, but will double-check its accuracy. For more information about getting your water tested, call the Southwest Fair Housing Council at (520) 798-1568. If you do not live in Tucson, Arizona, call 1-888-LEADLIST or go online to www.leadlist.org