Lead in drinking water from the source of the water is uncommon in Maine, regardless of whether the source is a well or municipal water district. However, lead in drinking water can occur due to corrosion of household plumbing containing lead. This can be accelerated where the water has high acidity or low mineral content that corrodes pipes and fixtures. Lead in drinking water can also be the result of industrial pollution. The focus of this article is lead from household plumbing.
The most common sources of lead in drinking water are lead pipes, faucets, and fixtures. However, even if the plumbing in a house does not contain lead there may still be lead in the drinking water if there is lead in the pipes that connect the house to the municipal water main. These lines, known as services lines, are often the most significant source of lead in the water. Lead pipes are more likely to be found in older cities and homes built before 1986. According to the EPA, in homes without lead service lines, the most common problem is with brass or chrome-plated brass faucets and plumbing with lead solder.
Major toxic effects of lead include anemia, neurological dysfunction/damage and renal impairment. Young children, infants, and fetuses are particularly at risk from exposure to lead because the physical and behavioral effects of lead occur at lower exposure levels in children than in adults. A dose of lead that would likely have little effect on an adult can have a significant effect on a child. Low levels of lead exposure in children have been linked to damage to the central and peripheral nervous system, learning disabilities, shorter stature, impaired hearing, and impaired formation and function of blood cells.
As a general rule bathing and showering in water containing elevated lead is considered safe for adults and children as human skin does not absorb lead in water.
Lead was a very common element in plumbing for decades. The Safe Drinking Water Act (SDWA) which was originally passed in 1974, was amended in 1986 and 1996 to reduce the maximum allowable lead content in plumbing — that is, content that is considered “lead-free” — to 0.25 percent of pipes, pipe fittings, plumbing fittings, and fixtures and 0.2 percent for solder and flux. . In 2011, Congress passed the Reduction of Lead in Drinking Water Act (RLDWA) revising the definition of lead-free by lowering the maximum lead content of the wetted surfaces of plumbing products. However, many homes, schools and buildings that stand today were constructed before this ban.
The EPA recommends the following to reduce the possible exposure to lead in drinking water in your home:
- Use only cold water for drinking, cooking and making baby formula. Boiling water does not remove lead from water.
- Regularly clean your faucet screen (also known as an aerator).
- Consider using a water filter certified to remove lead and know when it’s time to replace the filter.
- Before drinking, flush your pipes by running your tap, taking a shower, doing laundry or a load of dishes.
- Contact your water system to learn more about sources of lead and removing lead service lines.
The EPA maximum contaminant level for lead in drinking water is 0.015 mg/L. The State of Maine Maximum Exposure Guideline (MEG) for lead is 0.010 mg/L. Since you cannot see, taste, or smell lead dissolved in water, testing is the only way to determine whether there are harmful levels of lead in your drinking water.
A standard comprehensive water test includes testing for lead from the water source. To test for lead form the plumbing it is necessary to collect a sample after the water has been sitting in the plumbing for a minimum of 6 to 10 hours. This test, referred to as a First Draw Lead test, is simple and relatively inexpensive. It can be included in a comprehensive water quality test or as a stand alone test. The test can be performed by the home owner using an accredited lab or by a qualified contractor such as S & J Property Services.
It is recommended that the drinking water in homes built in 1986 or earlier be tested for lead from the plumbing regardless of whether the water comes from a well or municipal water source. S & J Property Services has tested multiple properties where the water source is a municipal water district which have had elevated lead from the plumbing, including at least one home where all of the plumbing in the house had been replaced within the the last 10 years. Out of the last 10 First Draw Lead tests performed by S & J Property Services for homes which have a municipal water supply 3 of the 10 had elevated levels of lead ranging from .0253 mg/L to .198 mg/L. As stated above, the EPA maximum contaminant level for lead in drinking water is 0.015 mg/L and the Maine MEG for lead is 0.010 mg/L.
If you do have your water tested and elevated lead is detected there are options for addressing the situation. The option which works best for your home will depend on a number of variables including the level of lead, the pH level of the water, and the age and condition of the plumbing in the house. In considering your options I recommend consulting with a water quality expert such as Norlen’s Water Treatment. (http://www.norlenswaterllc.com/)
For more information on lead in drinking water please refer to the following sources: