lead (pb) test

test overview

this test measures the amount of lead in a person's blood. lead is a poisonous (toxic) metal that can damage the brain and other parts of the body. a lead test may be done on blood taken from the vein, a finger (finger stick), or the heel (heel stick).

a person can be exposed to lead:

• by eating or drinking lead-contaminated foods, water, or other material (such as paint chips).
• by breathing dust or smoke containing lead.
• through skin contact with lead.

there is no safe age to be exposed to lead. a pregnant woman who is exposed to lead can pass it to her baby (fetus). lead can also be passed to a baby through the mother's breast milk.

why it is done

testing for lead is done to:

• diagnose lead poisoning.
• see how well treatment for lead poisoning is working.
• look for lead poisoning in people who work with lead or lead products or who live in places where the chance of poisoning is high, such as in a large city.
• check for the amount of lead in people who live with or play with children who have lead poisoning.

how to prepare

• in general, there's nothing you have to do before this test, unless your doctor tells you to.
• be sure to tell your doctor if you are using any natural health products.

how it is done

blood sample from a heel stick

a heel stick is used to get a blood sample from a baby. the baby's heel is poked, and several drops of blood are collected. your baby may have a tiny bruise where the heel was poked.

blood sample from a vein

a health professional uses a needle to take a blood sample, usually from the arm.

watch

how it feels

blood sample from a heel stick

a brief pain, like a sting or a pinch, is usually felt when the lancet punctures the skin. your baby may feel a little discomfort with the skin puncture.

blood sample from a vein

when a blood sample is taken, you may feel nothing at all from the needle. or you might feel a quick sting or pinch.

risks

heel stick

there is very little risk of a problem from a heel stick. your baby may get a small bruise at the puncture site.

blood test

there is very little chance of having a problem from this test. when a blood sample is taken, a small bruise may form at the site.

results

each lab has a different range for what's normal. your lab report should show the range that your lab uses for each test. the normal range is just a guide. your doctor will also look at your results based on your age, health, and other factors. a value that isn't in the normal range may still be normal for you.

results are usually available within 1 week.

your doctor will likely want to do more evaluation and another blood lead level test if:

• your child age 1 to 5 years has a blood lead level of 0.24 micromoles per litre (mcmol/l) or higher or 5 micrograms per decilitre (mcg/dl) or higher.
• your older child or you have a blood lead level around 0.48 mcmol/l or higher or 10 mcg/dl or higher.