Blood lead level
level of lead in blood
Blood lead level (BLL) is a measure of the amount of lead in the blood. Lead is a toxic heavy metal and can cause neurological damage, especially among children, at any detectable level. High lead levels cause decreased vitamin D and haemoglobin synthesis as well as anemia, acute central nervous system disorders, and possibly death.
Pre-industrial human BLL measurements are estimated to have been 0.016 μg/dL, and this level increased markedly in the aftermath of the industrial revolution. At the end of the late 20th century, BLL measurements from remote human populations ranged from 0.8 to 3.2 μg/dL. Children in populations adjacent to industrial centers in developing countries often have average BLL measurements above 25 μg/dL. In the United States, the average blood level for children aged 1–5 years fell from 15.2 μg/dL in 1976–1980 to 0.83 μg/dL in 2011–2016, a change largely attributed to phasing out leaded gasoline.
No level of lead in the blood of children is currently thought to be safe, but in 2021, the US Centers for Disease Control and Prevention (CDC) identified 3.5 μg/dL as the blood lead level of concern in children which should prompt further medical investigation. Approximately 2.5% of American children have at least this much lead in their blood.
Measurement
Measuring a person's blood lead level requires a blood sample, which may be performed with a fingerstick or a blood draw.
The amount of lead found in the blood sample may be measured in micrograms of lead per deciliter of blood (μg/dL) especially in the United States; 5 μg/dL is equivalent to 0.24 μmol/L (micromolar).
BLL cannot measure long-term lead exposure.
“Blood lead level” enters the record as level of lead in blood. Crown Archives preserves that source wording while asking what Blood, lead and level can confirm, complicate or overturn.
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This entry incorporates text from “Blood lead level” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.