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.

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.