Condition Basics

What is lead poisoning?

Lead poisoning occurs when you absorb too much lead by breathing or swallowing a substance with lead in it, such as paint, dust, water, or food. Lead can damage almost every organ system.

In children, too much lead in the body can cause lasting problems with growth and development. These can affect behaviour, hearing, and learning and can slow the child's growth.

In adults, lead poisoning can damage the brain and nervous system, the stomach, and the kidneys. It can also cause high blood pressure and other health problems.

Although it isn't normal to have lead in your body, a small amount is present in most people. Environmental laws have reduced lead exposure in Canada, but it is still a health risk, especially for young children.

What causes it?

Lead poisoning is usually caused by months or years of exposure to small amounts of lead at home, work, or daycare. It can also happen very quickly with exposure to a large amount of lead. Many things can contain or be contaminated with lead: paint, air, water, soil, food, and manufactured goods.

The most common source of lead exposure for children is lead-based paint and the dust and soil that are contaminated by it. This can be a problem in older homes and buildings.

Adults are most often exposed to lead at work or while doing hobbies that involve lead.

What puts you at risk?

Lead poisoning can occur at any age, but children are most likely to be affected by high lead levels. Higher lead levels can be found in:

• Buildings built before 1976. These buildings may have lead-based paint. The risk is even higher in buildings built before 1950, when lead-based paint was more commonly used.
• Buildings in other countries that do not regulate lead levels.

Children are at higher risk because:

• They often put their hands and objects in their mouths.
• They sometimes swallow non-food items.
• Their bodies absorb lead at a higher rate.
• Their brains are developing quickly.

Other things that increase risk include:

• Water that flows through pipes that were soldered with lead.
• Lead from metal smelters, pottery, or stained glass.
• Ceramic cookware from countries that do not regulate lead levels.
• Industrial pollution.

What are the symptoms?

You may not notice any symptoms at first. The effects of lead poisoning are easy to miss and may seem related to other conditions. The higher the amount of lead in the body, the more severe the symptoms are.

In children, symptoms can include:

• Damage to the brain and nervous system. Children may be smaller than other kids the same age.
• Behaviour problems, such as acting angry, moody, or hyperactive.
• Learning problems.
• Lack of energy, and not feeling hungry.

In adults, lead poisoning can cause:

• Changes in behaviour, mood, personality, and sleep patterns.
• Memory loss and trouble thinking clearly.
• Weakness and muscle problems.
• Headaches.

Severe cases can cause seizures, paralysis, and coma.

How is it diagnosed?

The doctor will ask questions and do a physical examination to look for signs of lead poisoning. If your doctor suspects lead poisoning, your doctor will do a blood test to find out the amount of lead in the blood.

Diagnosing lead poisoning is difficult, because the symptoms can be caused by many diseases. Most children with lead poisoning don't have symptoms until their blood lead levels are very high.

There are screening programs to check lead levels in children who are likely to be exposed to lead. Whether your child needs to be tested depends in part on where you live, how old your housing is, and other risk factors. Talk to your child's doctor about whether your child is at risk and should be screened.

Adults usually aren't screened for lead poisoning unless they have a job that involves working with lead. For these workers, companies usually are required to provide testing.

If you are pregnant or trying to get pregnant and have a family member who works with lead, you may want to ask your doctor about your risk for lead poisoning.

How is lead poisoning treated?

Treatment for lead poisoning includes removing the source of lead, getting good nutrition, and, in some cases, having chelation therapy.

Removing the source of lead.

Old paint chips and dirt are the most common sources of lead in the home. Lead-based paint, and the dirt and dust that come along with it, should be removed by professionals. In the workplace, removal usually means removing lead dust that's in the air and making sure that people don't bring contaminated dust or dirt on their clothing into their homes or other places.

Good nutrition.

Eating foods that have enough iron and other vitamins and minerals may be enough to reduce lead levels in the body. A person who eats a balanced, nutritious diet may absorb less lead than someone with a poor diet.

Chelation therapy.

If removing the lead source and getting good nutrition don't work, or if lead levels are very high, you may need to take chelating medicines. These medicines bind to lead in the body and help remove it.

If blood lead levels don't come down with treatment, home and work areas may need to be rechecked. Call your local health unit to see what inspection services are offered in your area.

The best way to avoid lead poisoning is to prevent it. Treatment cannot reverse any damage that has already occurred. But there are many ways to reduce your exposure—and your child's—before it causes symptoms.