There are a lot of questions being asked nowadays about lead contamination in water, including how lead is removed from water.
In most cases, lead is not present in the water source. When lead is present, water treatment may remove it and other contaminants, but toxins may be reintroduced to the clean water through the water delivery system.
Health risks are possible in adults who consume water containing high levels of lead, including kidney problems or high blood pressure, notes the U.S. Environmental Protection Agency.
The risks for children are even higher, and include possible developmental problems.
Does Your Water Contain Lead?
Lead is colorless, odorless, and tasteless in water, making testing mandatory. There are different types of tests possible. The Penn State Extension advises homeowners to collect two samples when testing home water for lead — a sample immediately upon using the tap first thing in the morning and another after the water has been allowed to run. Analyzing these samples will determine the sources of the 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. The lead may originate from water supply contamination, from corroding submersible pump parts, or from corroding lines in a public water system.
In the U.S., the problem is seen in homes built before 1986. Even so-called “lead-free” plumbing may contain up to 8 percent lead. According to the EPA, brass or chrome-plated brass faucets and fixtures can “leach significant amounts of lead into the water, especially hot water.”
However, because lead contamination of drinking water often results from corrosion of the plumbing materials belonging to water system customers, EPA established a treatment technique […] an enforceable procedure or level of technological performance which water systems must follow to ensure control of a contaminant.
Testing is critical for individuals who live in homes not connected to a public water supply. Well water must be tested regularly to ensure it is safe to drink.
Preventing Lead Leaching
Water systems are required to control the corrosivity of the water to keep lead from leaching into the water supply. The EPA also mandates collecting samples based on specific parameters, which may include replacing lead service lines.
These rules were last revised in 2007. State governments may have stricter guidelines in place for drinking water than the EPA.
It is essential to note that boiling or heating water will not remove lead from the water. It may worsen the situation. Hot water dissolves lead. The process of heating the water can concentrate the lead somewhat when it reaches the boiling point. Flushing the water system may be a better stop-gap measure, experts say.
Filtration and Other Solutions
Homeowners can install a reverse osmosis or distillation unit, or carbon filters designed to remove lead on every faucet in the home. These aren’t always ideal solutions, especially when considering the cost versus the volume of safe water produced.
The most effective course of action is to replace older home plumbing — including copper pipe and lead solder — with the newest, lead-free components. This is often plastic piping, such as PVC. If, however, lead service lines within a public water system are the source of the problem, replacement will not be effective.
If using a private well, the Centers for Disease Control recommends looking at both the well and pump as potential lead sources.
For more information about the U.S. Safe Drinking Water Act, visit the EPA or contact your local water authority or health department for more information.
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