CDC’s current blood lead reference value is 3.5 µg/dL, based on the 97.5th percentile for U.S. children ages 1–5 in NHANES 2015–2018. CDC states that no safe blood lead level in children has been identified.
The BLRV is a population-based measurement. It now indicates that 2.5% of U.S. children aged 1–5 years have BLLs at or above 3.5 μg/dL. It is not a health-based standard or a toxicity threshold.
CDC’s current blood lead reference value is 3.5 µg/dL, based on the 97.5th percentile for U.S. children ages 1–5 in NHANES 2015–2018. CDC states that no safe blood lead level in children has been identified. Current page checked October 2026. The reference value identifies children with higher levels than most children; it is not a toxicity threshold or a statement that lower levels are harmless.