That old house you bought has wonderful charm and gorgeous details, like crown moldings or built-in bookshelves. But it also may have a throw-back you can’t see: lead paint.

Many homes built before 1978 have lead-based paint, according to the Environmental Protection Agency (EPA). As this paint chips and deteriorates, it creates lead dust. If the kids in your house breathe it in or ingest it, it can lead to serious health problems such as learning difficulties, behavior problems, slowed growth, hearing problems and hyperactivity, according to the EPA.

Lead is particularly dangerous to children because their growing bodies can absorb more lead than adults’ bodies, the EPA says. Their brains and nervous systems are also more sensitive to the effects of lead. Since they put their hands everywhere and then put them in their mouths, they’re more exposed to lead dust.

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Lead poisoning symptoms can include nausea, headaches, weight loss, constipation, abdominal pain and muscle weakness, according to KidsHealth.org. Some kids with lead poisoning will show no symptoms. A blood test can measure the amount of lead in a child’s blood.

About 24 million homes have deteriorated lead paint and elevated levels of lead dust, according to UL. Children live in more than 4 million of these homes, according to the Centers for Disease Control and Prevention (CDC).

The CDC says the most important step parents can take regarding lead poisoning is to prevent it from happening. Here’s how.

1. Test for lead paint. Talk to your local health department about testing for lead paint and dust in your home if it was built before 1978, the CDC says.

2. Renovate using lead-safe practices. Home renovation activities like sanding, cutting or demolition can kick up lead dust and should be performed by contractors certified in the EPA’s lead-safe work practices.

3. Keep kids away from peeling paint. And if you see paint chips or dust from peeling paint on windowsills or floors, clean those areas regularly with a wet mop or cloth.

4. Stay on top of product recalls. If you own a toy or product recalled due to lead paint, throw it away.

5. Drink cold tap water only. Water may pick up lead from the plumbing in an old house. Use only cold tap water for drinking and cooking since hot water from the tap is more likely to contain higher levels of lead, UL says.

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Angela is a Pulitzer Prize-winning digital editor with more than 15 years of experience delivering news and information to audiences worldwide. Prior to joining SafeBee, she was the features editor for Boston.com at The Boston Globe, overseeing health, travel, entertainment, business and lifestyle coverage. Before moving to features, she was the news and homepage editor, covering stories such as the Boston Marathon bombing, Red Sox World Series victories, presidential elections, a papal inauguration, and more. Her favorite safety tip: Clean your phone! The average cell phone has 18 times more germs than the toilet handle in a men’s restroom.