Did you know that the chemical symbol for lead of “Pb” comes from the Latin plumbum, the root word for “plumbing”? Lead is a soft, malleable and corrosion resistant metal, that throughout much of history and before the scientific advancements of the 20th century revealed its toxicity. Lead has been used as an ingredient in a variety of products such as, gasoline, paint, glassware, metal pipes, food containers, etc., all of which have contained varying amounts of lead.
The lead that most people can be exposed to is commonly found in two main areas of a home. First, lead-based paint is frequently found in homes and apartments constructed prior to 1978; and second, in water pipes, pipe solder and plumbing fixtures.
Lead-Based Paint Testing and Removal
It appears that the traditional paint of choice that flourished during the Renaissance period and used throughout the European guildhalls was lead-based paint. Lead-based paint was shipped to the Colonies of the United States as a luxury good and is reported to have been used to paint such important structures as the White House and the Capitol building.
Through the early 1900s, many professional painters hand-mixed white lead with oil to make paint for specific job requirements. Some were aware of the potential risk from exposure to lead but preferred to use white lead in oil because they believed that it was superior to non-lead paints. When lead-based paint was marketed by paint manufactures, it was advertised as a better product and was in high demand because it was washable, flexible and durable. It was frequently endorsed by state and local governments and specified for use on government buildings until the 1970s.
Lead-based paint has been banned by the Consumer Products Safety Act in 1978. In homes where paint would be older than this, it should be assumed that lead is present. Lead paint is still present in millions of homes, many times under layers of newer paint. If the paint is in good shape, the lead paint is usually not a hazard. Deteriorating lead-based paint (peeling, chipping, chalking, cracking or damaged) is a potential health risk and should be given immediate attention. Other areas of concern are impact or friction surfaces, like windows and doors.
Lead-based paint is defined by the Federal Government as paint, varnish, shellac or other coatings on surfaces that contain 1.0 milligram per square centimeter (mg/cm2), or more of lead or than 0.5percent or more lead by weight.
Lead paint removal is a necessary process, in many cases, to protect the occupants of a home or commercial facility where it is present. The abatement process has to follow certain guidelines for removal and disposal and should only be performed by a licensed contractor.
Federal Law and Lead Paint
Federal law requires disclosure of known lead-based paint and/or lead-based paint hazards by persons selling or leasing housing constructed before 1978. Under such law, a seller or lessor is required to accomplish the following:
- Disclose to the purchaser or lessee the presence of any known lead-based paint and/or lead-based paint hazards.
- Provide available records and reports.
- Provide the lessee with a lead hazard information pamphlet.
- Provide purchasers a 10-day opportunity to conduct a risk assessment or inspection.
- Attach specific disclosure and warning language to the sales or leasing contract before the purchaser or lessee is obligated under a contract to purchase.
Water Testing For Lead
Some major U.S. cities still have service water lines with lead piping bringing water from the utilities to homes and businesses. The use of lead pipes in water systems started in the late 1800s, lead pipes were favored for their resistance to corrosion and malleability, which made installation easy; by the 1920s awareness of health risks associated with the use of lead pipes raised and their use was banned by most municipalities. According to a nationwide survey conducted by the EPA in 1984 of 153 municipalities with population over 100,000, 73% of the municipalities surveyed indicated to have installed service lines with lead pipes in the past, and some of them indicated doing it well beyond the 1930s. The use of lead pipes in water systems was finally prohibited nationwide in 1986 by the Safe Drinking Water Act Amendments of that date.
Another major source of lead in drinking water is the solder that was used to join copper pipes together. The solder was an alloy that is comprised of a mixture of tin with lead, antimony, or silver. As water sits in the copper pipes for extended periods of time, small amounts of lead leach out of the solder and into the drinking water. Copper pipes with lead solder were very common in households from the 1940s through the early 1980s.
Lead can also corrode from metal faucets and fixtures made from brass. Brass is an alloy of copper and zinc that often contains lead impurities, including chrome-plated brass fixtures. Fixtures manufactured prior to 2014 may be a potential source of lead, especially when using hot water. Brass fixtures can leach lead even in homes with plastic or PVC water lines. Lead may also originate from the corrosion of brass fittings on certain types of submersible pumps used in groundwater wells through the mid-1990s. Laws have restricted the amount of lead allowed in new pipes, fixtures, and solder but many homes contain older materials.
The amount of lead corroded from metal plumbing generally increases as water corrosiveness increases. Water corrosiveness is controlled primarily by the water’s acidity and calcium carbonate content. In addition to acidity and calcium carbonate, many other factors can influence water’s corrosiveness. Soft water (low in dissolved solids) tends to be more corrosive than hard water (with high concentrations of calcium and magnesium), and warm water is more corrosive than cold water. The common practice of grounding electrical connections to water pipes also can increase lead corrosion.
Lead Levels and Your System
In general, lead concentrations in drinking water usually are the highest in the first water out of the tap after the water has been sitting in the piping for a few hours; they decrease as the water is run. If lead pipes, leaded solder, or brass fixtures are present, even relatively noncorrosive water can dissolve small amounts of lead if the water sits in contact with these materials for more than a few hours.
If you are planning on testing your water system, it is recommended that you collect a minimum of two water samples. The first is a “first-draw” sample collected first thing in the morning from cold water that has sat in the plumbing system overnight. This sample determines if lead accumulates in your water as it sits in contact with the plumbing system.
The second is a “flush” sample collected after allowing the cold water to run for approximately one minute. The second sample is important for comparing the results and helps you determine the source of a lead problem. A lead concentration that remains above 15 µg/L after the water has run for one to two minutes indicates that lead is probably present in the water before it enters the household plumbing.
Minimize Risks of Lead Poisoning
If you live in an older home; there are a few precautions recommended by the US Department of Housing and Urban Development to help minimize your risks of lead poisoning from lead-based paint, contaminated soil and lead water pipes.
- Wipe down flat surfaces with a damp paper towel and throw away the paper towel.
- Mop smooth surfaces with a damp mop to control dust.
- Take off shoes off when entering the house to avoid tracking in the dirt that may be contaminated.
- Vacuum carpets to remove dust, ideally with a HEPA filter.
- Pick up loose paint chips with a damp paper towel.
- Use only cold water for drinking and cooking.
- Run water for 15 to 30 seconds before drinking it, especially if you have not used your water for a few hours.
- Test for lead by calling a professional like Alpha Environmental.
If you have an older home or are concerned that you might have lead in either paint around your home or in your water system, call Alpha Environmental for a lead paint testing or lead in water testing today. We can provide more information for your Portland-area home and schedule an appointment if you desire. Call us at 503-292-5346.