By Megan Boyle, Editorial Director and Sonya Lunder, Senior Analyst

The drinking water crisis in Flint, Michigan, has people across the country wondering: how can I tell if our tap water is polluted with lead?

As has been widely reported, lead pipes or the solder that connects them may leach lead into tap water. Municipal water utilities may be responsible for these pipes, or they may be inside your home.

How much lead is in your family’s tap water can vary considerably, from tiny amounts to concentrations well above the U.S. Environmental Protection Agency’s action limit – 15 parts per billion in water. That’s the level at which public utilities must inform the public about lead contamination and take steps to stop it from migrating from pipes into water.

But even water contaminated at lower concentrations than 15 parts per billion can be harmful, especially to kids and pregnant women. The U.S. Centers for Disease Prevention and Control says that “No safe blood lead level in children has been identified.”

Here are the questions you need to ask:

Is the plumbing in my neighborhood or home exposing my family to lead?

Ask your water provider if your tap water enters your home through a lead service line. Although most utilities stopped installing lead lines decades ago, the nation’s aging infrastructure still counts between 3.3 and 6.4 million lead service lines, particularly in older neighborhoods in the Northeast and Midwest.

A 1986 amendment to the federal Safe Drinking Water Act banned the use of lead in plumbing materials, but nearly all houses and apartments built before then still use copper pipes connected by lead solder. As these older pipes and fixtures corrode or the soldering breaks down, lead particles can get into your tap water.

Check your utility’s water report or independently test your water if you live in a structure built before 1986. Newer houses pose less risk but could still harbor lead in the plumbing: the 1986 amendment to the Safe Drinking Water Act allowed “lead-free” pipes to contain up to 8 percent lead, or solder and flux up to 0.2 percent. Congress did not tighten these restrictions until 2011.

Does my water utility test its output and take measures to reduce lead contamination?

Since lead gets into water after it leaves the treatment plant, the EPA requires water utilities to test lead content in customer residences and take action if the lead level reaches 15 parts per billion in more than 10 percent of tested homes.

But the EPA regulations contain some important loopholes: they exempt water systems serving fewer than 25 people and well water from the residential lead testing requirement. This exemption affects some 40 million to 45 million Americans.

How do I get the test results for my water?

Public drinking water utilities that regularly test water for contaminants are required to disclose their results. If you live within a utility’s boundaries and do not receive this information by mail, call its local office to request a copy of the report or look for it on the utility’s website. You can call EPA’s Safe Drinking Water Hotline at (800) 426-4791 to learn how to get your results.

Consider testing your own tap water if: any homes in your community test positive for lead, if your family lives in a remote or small community that does not test tap water, or if you drink well water.

Test your water through a state-certified commercial laboratory. Labs generally recommend that you collect a sample of cold water that has sat overnight and another sample of cold water after you have run the tap for one minute. The EPA sets its action level at 15 micrograms per liter (ug/L) or parts per billion (ppb), a measurement equivalent to 0.0015 milligrams per liter (mg/L) or parts per million (ppm).

If the utility’s tests or your own lab tests detect lead in your water, use a water filter and, if the lead is coming from your own pipes, consider replacing them, especially if you have kids or pregnant women at home. If you find more than 15 parts per billion of lead in your water, contact your local utility or water authority to find out what you should do next.

Click here to learn how to filter your water to reduce lead.