Q: How much lead is too much?
A: Federal standards initially limited the amount of lead in water to 50 parts per billion (ppb). In light of new health and exposure data, EPA has set an action level of 15 ppb. If tests show that the level of lead in your household water is in the area of 15 ppb or higher, it is advisable - especially if there are young children in the home - to reduce the lead level in your tap water as much as possible. (EPA estimates that more than 40 million U.S. residents use water that can contain lead in excess of 15 ppb.) Note: One ppb is equal to 1.0 microgram per liter (µg/1) or 0.001 milligram per liter (mg/1).

Q: How can I reduce my exposure
A: If your drinking water is contaminated with lead - or until you find out for sure - there are several things you can do to minimize your exposure. Two of these actions should be taken right away by everyone who has, or suspects, a problem. The advisability of other actions listed here will depend upon your particular circumstances.

The first step is to refrain from consuming water that has been in contact with your home's plumbing for more than six hours, such as overnight or during your work day. Before using water for drinking or cooking, "flush" the cold water faucet by allowing the water to run until you can feel that the water has become as cold as it will get. You must do this for each drinking water faucet-taking a shower will not flush your kitchen tap. Buildings built prior to about 1930 may have service connectors made of lead. Letting the water run for an extra 15 seconds after it cools should also flush this service connector. [2/26/04 NOTE: Longer flushing times may be needed to respond to local conditions.] Flushing is important because the longer water is exposed to lead pipes or lead solder, the greater the possible lead contamination. (The water that comes out after flushing will not have been in extended contact with lead pipes or solder.)

Once you have flushed a tap, you might fill one or more bottles with water and put them in the refrigerator for later use that day. (The water that was flushed - usually one to two gallons - can be used for non-consumption purposes such as washing dishes or clothes; it needn't be wasted.)

Note: Flushing may prove ineffective in high-rise buildings that have large-diameter supply pipes joined with lead solder

The second step is to never cook with or consume water from the hot-water tap. Hot water dissolves more lead more quickly than cold water. So, do not use water taken from the hot tap for cooking or drinking, and especially not for making baby formula. (If you need hot water, drawwater from the cold tap and heat it on the stove.) Use only thoroughly flushed water from the cold tap for any consumption.

Other Actions:

• If you are served by a public water system contact your supplier and ask whether or not the supply system contains lead piping, and whether your water is corrosive. If either answer is yes, ask what steps the supplier is taking to deal with the problem of lead contamination. Drinking water can be treated at the plant to make it less corrosive. (Treatment to reduce corrosion will also save you and the water supplier money by reducing damage to plumbing.) Water mains containing lead pipes can be replaced, as well as those portions of lead service connections that are under the jurisdiction of the supplier.
• If you own a well or another water source, you can treat the water to make it less corrosive. Corrosion control devices for individual households include calcite filters and other devices. Calcite filters should be installed in the line between the water source and any lead service connections or lead-soldered pipe. You might ask your health or water department for assistance in finding these commercially, available products.
• A number of cartridge type filtering devices are available. These devices use various types of filtering media, including carbon, ion exchange resins, activated alumina and other privately marketed products. Unless they have been certified as described below, the effectiveness of these devices to reduce lead exposure at the tap can vary greatly. It is highly recommended that before purchasing a filter, you verify the claim made by the vendor. If you have bought a filter, you should replace the filter periodically as specified by the manufactuer. Failure to do so may result in exposure to high lead levels.

For more details on the problem of lead in drinking water and what you can do about it, read the questions and answers in the remainder of this booklet. Your local or state department of health or environment might be able to provide additional information.