Lead

Under The Safe Drinking Water Act, the EPA determines the level of contaminants in drinking water at which no adverse health effects are likely to occur. These non-enforceable health goals are called maximum contaminant level goals (MCLGs). For most contaminants, the EPA also sets an enforceable regulation called a maximum containment level (MCL) which sets the highest level of a containment allowed in drinking water to protect people from unsafe drinking water. MCLs are usually set as close to the MCLGs as possible.

Significantly, the EPA has set the MCLG for lead in drinking water at zero because lead is a toxic metal that can be harmful to human health even at low exposure levels. However, because lead contamination of drinking water often results from corrosion in the plumbing systems of individual customers, the EPA established a treatment technique rather than an MCL for lead. (A treatment technique is an enforceable procedure or level of technological performance that water systems must follow to control a contaminant.)

The treatment technique regulation for lead, referred to as the Lead and Copper Rule, requires water systems to control the corrosivity of the water and to collect tap samples from sites that are more likely to have lead containing plumbing materials. If more than 10% of tap water samples exceed the lead action level of 15 parts per billion, water systems are required to optimize their corrosion control treatment, educate the public, and replace portions of lead service lines. Our personal water testing device can detect lead in water at the EPA’s lead action level of 15 PPB and can alert users immediately if there is a problem.

Lead can enter drinking water when service pipes that contain lead corrode, especially where the water has high acidity or a low mineral content that corrodes pipes and fixtures. The most common problem is with brass or chrome-plated brass faucets and fixtures with lead solder, from which significant amounts of lead can enter into the water, especially hot water.

Homes built before 1986 are more likely to have lead containing plumbing materials.. The Safe Drinking Water Act (SDWA) reduced the maximum allowable lead content -- that is, content that is considered "lead-free" -- to be a weighted average of 0.25 percent calculated across the wetted surfaces of pipes, pipe fittings, plumbing fittings, and fixtures and 0.2 percent for solder and flux. While homes built before 1986 are more likely to have lead pipe issues, new homes are also at risk becauseeven legally "lead-free" plumbing can contain up to 8% lead.

A number of factors influence the amount of lead that enters the water, including the chemistry of the water, the types and quantities of minerals in the water, the temperature of the water, the amount of lead the water physically comes into contact with, the amount of wear in the pipes, the amount of time the water sits in the pipes, and the protective coatings inside the plumbing system.

Young children, infants, and fetuses are particularly vulnerable to lead because the physical and behavioral effects of lead occur at lower exposure levels in children than in adults. Therefore, a dose of lead that would have little effect on an adult can have a significant effect on a child. In children, low levels of exposure 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.

The Centers for Disease Control and Prevention (CDC) recommends that public health actions be initiated when the level of lead in a child’s blood is 5 micrograms per deciliter (µg/dL) or more.

It is important to recognize all the ways a child can be exposed to lead. Children are exposed to lead in paint, dust, soil, air, and food, as well as drinking water. If the level of lead in a child's blood is at or above the CDC action level of 5 micrograms per deciliter, it may be due to lead exposures from a combination of sources. The EPA estimates that drinking water can make up 20 percent or more of a person’s total exposure to lead. Infants who consume mostly mixed formula can receive 40 percent to 60 percent of their exposure to lead from drinking water.

Even low levels of lead in the blood of children can result in behavior and learning problems, lower IQ and hyperactivity, slowed growth, hearing problems, and anemia. In rare cases, ingestion of lead can cause seizures, coma and even death.

Lead can accumulate in the body over time, where it is stored in bones along with calcium. During pregnancy, lead is released from bones as maternal calcium and is used to help form the bones of the fetus. This is particularly true if a woman does not have enough dietary calcium. Lead can also cross the placental barrier exposing the fetus to lead. This can result in serious effects to the mother and her developing fetus, including reduced growth of the fetus and premature birth.

Lead is also harmful to adults. Adults exposed to lead can suffer from cardiovascular effects, increased blood pressure and incidence of hypertension, decreased kidney function, and reproductive problems (in both men and women).

Since you cannot see, taste, or smell lead dissolved in water, testing is the only sure way of telling whether there are harmful quantities of lead in your drinking water. Water testing is a crucial step in dealing with the problem of lead in drinking water and is even recommended by the EPA. Also, since each home has different plumbing, pipes, and materials, test results are likely to be different for each home. Our personal water tester, the TestDrop Pro, can efficiently detect the presence of lead in your water so you can be sure of conditions in your own home. For more information or to place an order, click here.