Lead (Blood)
Does this test have other names?
Serum lead level, BLL, blood lead test
What is this test?
This test measures the amount of lead in your child's blood. It can find out whether
your child has been exposed to lead.
Before 1978, lead was a major ingredient in household paint. It still can be found
in older homes and in the soil around them. Children can inhale lead dust or chew
on items that use lead-based paint. No safe lead blood level for children has been
identified. High levels of lead in the blood can be toxic.
Why does my child need this test?
Your child may need this test if they are at high risk for lead exposure or if your
insurance company needs lead testing in children. Children under the age of 6 are
at particular risk for lead poisoning. Young children can put their hands on objects
that may be contaminated with lead and then put their hands in their mouths. In addition,
children living in older housing or areas that use lead pipes are also at a higher
risk for lead poisoning. If you live in a home built before 1978, your healthcare
provider might order this test to see if your child has been exposed to lead. Children
also are tested for lead if they have signs and symptoms of lead poisoning, including:
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Belly pain
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Anemia, or low red blood cell counts
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Nausea or vomiting
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Weight loss
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Extreme tiredness
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Muscle weakness
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Seizures
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Headache
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Hair loss
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Difficulty paying attention, behavior changes, or learning disabilities
This test is also used to see if treatment for lead poisoning is working.
What other tests might my child have along with this test?
If your child has higher than normal lead levels, the healthcare provider might order
a complete blood count to check for anemia, a condition in which the red blood count
is low. If your child has anemia, their body may not get enough oxygen.
Your child may also have these blood tests:
For children who need treatment for lead poisoning, more tests may be needed to see
if their kidneys and liver are working the way they should. These tests include:
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Serum electrolytes
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Blood urea nitrogen
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Creatinine
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Calcium
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Magnesium
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Liver function tests
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Urinalysis
What do my child's test results mean?
Test results may vary depending on your child's age, gender, health history, and other
things. Your child's test results may be different depending on the lab used. They
may not mean your child has a problem. Ask your healthcare provider what your child's
test results mean for them.
A test result greater than 3.5 micrograms per deciliter (mcg/dL) is considered high
and may mean your child has been exposed to lead. The higher the level of lead in
your child's blood, the greater the risk of learning disabilities, impaired growth,
and kidney and nerve damage.
How is this test done?
The test is done with a blood sample, which is drawn through a needle from a vein
in your child's arm. Blood samples from infants and children may also be collected
by a finger stick. If test results from a finger stick are abnormal, a sample of blood
drawn from a vein is usually done to confirm the results.
Does this test pose any risks?
Having a blood test with a needle carries some risks. These include bleeding, infection,
bruising, and feeling lightheaded. When the needle pricks your child's arm or finger,
they may feel a slight sting or pain. Afterward, the site may be sore.
What might affect my child's test results?
The test results reflect only recent exposure to lead.
Your child may get a false test result if:
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Blood is taken from your child's finger and they have dust or dirt on their hands.
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Your child is not getting enough calcium, iron, and vitamin C and eating too much
fat.
How do I get my child ready for this test?
Your child doesn't need to prepare for this test. Be sure your healthcare provider
knows about all medicines, herbs, vitamins, and supplements your child is taking.
This includes medicines that don't need a prescription and any illegal drugs that
your child may use.