Blood Lead Levels in Children

Protecting children from exposure to lead is important to lifelong good health. No safe blood lead level in children has been identified. Even low levels of lead in blood have been shown to affect IQ, ability to pay attention, and academic achievement. While the effects of lead poisoning are permanent, if caught early, there are things parents can do pdf icon[PDF – 234 KB] to prevent further exposure and reduce damage to their child’s health.

The most important step that parents, doctors, and others can take is to prevent lead exposure before it occurs.

Lead in the Blood and Body
Child's hand playing with colorful wooden blocks.

Lead exposure occurs when a child comes in contact with lead by touching, swallowing, or breathing in lead or lead dust. Lead quickly enters the blood and can harm your child’s health. Even after removing lead hazards from a child’s environment, blood levels do not drop right away, so prevention is key.

The health effects of exposure are more harmful to children less than six years of age because their bodies are still developing and growing rapidly.

Young children also tend to put their hands or other objects, which may be contaminated with lead dust, into their mouths, so they are more likely to be exposed to lead than older children.

Lead is quickly absorbed into the blood stream. Once a child ingests lead, their blood lead level rises. Once a child’s exposure to lead stops, the amount of lead in the blood decreases gradually. The child’s body releases some of the lead through urine, sweat, and feces. Lead is also stored in bones. It can take decades for the amount of lead stored in the bones to decrease.

Many things affect how a child’s body handles exposure to lead, including:

  • Child’s age.
  • Nutritional status.
  • Source of lead exposure.
  • Length of time the child was exposed.
  • Presence of other underlying health conditions.

Although lead in blood represents only a portion of the total amount of lead present in the body, a blood lead test is the best available way to assess a person’s exposure to lead.

Testing Blood Lead Levels

A blood test is the best and most readily available way to determine if a child has been exposed to lead. If your child may have been exposed to lead, talk to your healthcare provider about getting a blood lead test. Based on your child’s blood lead test results, healthcare providers can recommend follow-up actions and care.

During a blood lead test, a small amount of blood is taken from the finger or arm and tested for lead. Two types of blood tests may be used.

  • A finger-prick, or capillary, test is usually the first step to determine if a child has elevated blood lead levels. While finger-prick tests can provide fast results, they also can produce higher results if lead on the skin is captured in the sample. For this reason, a finger-prick test that shows an elevated result is usually followed by a second test to confirm.
  • A venous blood draw takes blood from the child’s vein. This type of test can take a few days to receive results and is often used to confirm elevated blood lead levels seen in the first capillary test.

Most children with any lead in their blood have no obvious immediate symptoms. If a child may have been exposed to lead, parents should talk to their child’s health care provider about getting a blood lead test. Healthcare providers and most local health departments can test for lead in the blood. Many private insurance policies cover the cost of testing for lead in the blood. Children covered by Medicaid can receive free testing.

CDC’s Blood Lead Reference Value

The amount of lead in blood is referred to as blood lead level, which is measured in micrograms of lead per deciliter of blood (μg/dL). CDC currently uses a blood lead reference value of 5 micrograms per deciliter to identify children with blood lead levels that are higher than most children’s levels. This value is based on the U.S. population of children ages 1-5 years who are in the highest 2.5 percent of children when tested for lead in their blood.

Treating Children with Elevated Blood Lead Levels

If a child has an elevated blood lead level, their doctor may recommend follow-up services. These include finding and removing lead from the child’s environment, feeding the child a diet high in iron and calcium, connecting the child to early educational services, and scheduling follow-up blood testing. Early identification of elevated blood lead levels is key to reducing the long-term effects of lead exposure. If a child has very high levels of lead in their blood, health care providers may recommend other types of testing (such as an x-ray) or chelation therapy to remove some lead from the blood.

For more information on caring for children with elevated blood lead levels, refer to CDC’s Recommended Actions Based on Blood Lead Level.

Preventing Childhood Lead Exposure

Though lead can be found in many places in a child’s environment, lead exposure is preventable. The key is stopping children from coming into contact with lead. Parents can take simple steps to make their homes more lead-safe. For more information, refer to Lead Poisoning Prevention.

Additional Resources