Lead Blood Test

The test requires a small sample of blood which is collected by a finger stick or heel stick (in infants) method. 

The fingerstick method:

• Any finger on your palm will be cleansed with alcohol and squeezed slightly
• A sharp needle (lancet) will be used to make a quick puncture
• A drop of blood will then be collected onto a slide or test strip and sent to the laboratory for testing.

In the heel stick method performed in infants, the sample is collected from the heel in the same way as in the fingerstick method. 

If the initial test shows elevated lead levels in the blood, then a blood sample will be collected from a vein in your arm to confirm the results. 

After the venipuncture, you may notice a slight bruise at the site of blood withdrawal. Though it will subside on its own. If the bruising doesn’t disappear after a few hours, please contact your doctor.

If you are at risk of environmental exposure to lead, your doctor may order this test for you. The test is also done to monitor the treatment for high lead levels.

As per the local health guidelines, doctors recommend this test for the following at-risk groups:

• People living in poor housing conditions
• Children < 6 years of age
• Adults who work in industries known for lead exposure
• Families of workers with occupational lead exposure 
• People who live in areas with high lead contamination 
• Pregnant women exposed to lead 

Your doctor may order this test if you show symptoms of lead toxicity. The symptoms and signs of lead toxicity include:

• Loss of appetite
• Abdominal pain
• Fatigue
• Headache
• Weight loss
• Disorientation
• Difficulty in concentration and behavioural problems 
• Impaired memory 
• Fits and coma – in case of high exposure

Children presenting with the following symptoms may also be screened for lead toxicity:

• Hearing loss
• Speech problems
• Developmental delay
• Learning difficulties
• Sleep problems
• Anaemia
• Attention-deficit

You do not need any special preparation for this test. There is no need to fast either.

Normal results:

A normal result indicates the absence of lead or the presence of only traces of lead in the blood. Traces of lead are reported as negative as they do not cause the harmful effects stated above. If the lead concentration in blood is less than 5 µg/dL (micrograms per decilitre), it may be considered normal for adults.

There is no safe blood lead concentration for children and pregnant women.

Abnormal results:

Lead levels >5 µg/dL in the blood are considered abnormal. 

The following are the cut-off values for lead exposure in children and adults:

• Lead blood concentration between 5 and 10 µg/dL require follow-up. Individuals with blood lead levels of > 10 µg/dL are asked to evaluate their environment to locate and remove the possible sources of lead exposure.
• Chelation treatment should be considered if lead blood levels are > 40 µg/dL in individuals who show symptoms of lead toxicity. Chelation therapy includes the administration of specific drugs that bind to the toxic metal and helps expel it through the urine.
• Lead blood concentration of > 70 µg/dL is considered a medical emergency in adults whereas immediate treatment is recommended in children with lead levels of ≥ 45 µg/dL.

Disclaimer: All results must be clinically correlated with the patient’s complaints to make a complete and accurate diagnosis. The above information is provided from a purely educational point of view and is in no way a substitute for medical advice by a qualified doctor.