CDC Blood Lead Reference Value

Reads a blood lead level against the CDC blood lead reference value.

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Blood lead level
4.2 micrograms per deciliter
Sample type
Capillary (fingerstick)

Result: at or above the reference value of 3.5

The tool opens with these values already filled in. Replace them with your own.

What the result means

Under 3.5
Below the reference value. Not the same as no exposure: no level of lead in blood is known to be without effect.
3.5 and above
At or above the reference value. The response is to find and remove the source, not to give a drug.
45 and above
The level at which chelation is considered, with a specialist.
70 and above
A medical emergency.
It is 3.5, not 5
The value was lowered in 2021. Read against the old line, every result between 3.5 and 5 looks normal.
Not a safe level
It is the 97.5th percentile of the blood lead distribution among young children in the United States, which makes it a marker for more exposure than most rather than a threshold for harm.
A capillary result
Lead on the skin contaminates a fingerstick, so an elevated capillary result is confirmed venous before it is acted on.

What you enter

  • Blood lead level
  • Sample type
How this is calculated

Centers for Disease Control and Prevention. Blood Lead Reference Value. Atlanta: CDC; 2021. Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

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Built by Clay Good. Source on GitHub.