Skip to content
Blood Test Tracker

Lead, Blood

Measures lead in your blood, the standard test for recent lead exposure. Most people in the US have very low levels.

AI-verified against cited sources. Awaiting expert reviewAlso called Pb, BLL, PbBLOINC 5671-3

Check your result

Sex (optional)

Type your result to see where it falls.

Nothing you type here leaves your browser.

What it is

Lead is a metal that can get into the body from old paint and dust, drinking water from lead pipes, soil, some jobs and hobbies, and some imported products. This test measures how much is in your blood. It mostly reflects exposure over the past weeks to months, plus some lead that slowly leaks back from bone. In 2017-2018, a typical US adult had a level under 1 µg/dL.

Why it matters

Lead has no useful role in the body. Even low levels have been linked to higher blood pressure, kidney effects and changes in thinking in adults, and children and pregnancy are more sensitive. Finding a raised level lets you and your clinician look for the source, which is the main way to bring it down.

If it’s high

A higher result means more lead has been absorbed recently or over time. Most results just above the reference value are low-level and trace to a source at home, work or a hobby. Higher levels are more likely to cause symptoms such as abdominal pain, nausea, weakness or confusion, and very high levels need urgent care.

Common causes

  • Older homes with lead paint or lead dust
  • Drinking water from lead pipes or fixtures
  • Jobs or hobbies that involve lead, such as construction, battery or radiator work, firing ranges, stained glass or casting
  • Some imported items such as certain ceramics, cosmetics, spices or traditional remedies
  • Contaminated soil
  • Contamination of the sample, especially a fingerstick, which can falsely raise a result

What can help

  • Ask your clinician or local health department how to find and reduce lead sources at home or work
  • Ask whether children, pregnant people or others in your household should be tested
  • Ask about a repeat venous test if the first result came from a fingerstick

Usual ranges

What labs print as the reference range, by who was tested. Ranges differ a little between labs, so the range on your own report is the one your result is judged against.

For adults: up to 3.4 µg/dL. Source: Centers for Disease Control and Prevention, CDC / NIOSH, ARUP Laboratories. Labs treat above 70 µg/dL as urgent.

See Blood Lead by age and sex, with the U.S. survey numbers where they exist.

Adult interpretive guidance for clinical laboratories (Kosnett et al. 2007)

  • Under 5: no specific action suggested by this guidelinebelow 5 µg/dL
  • 5-9: discuss health risks; reduce exposure in pregnancy5 to under 10 µg/dL
  • 10-19: discuss risks, decrease exposure, monitor10 to under 20 µg/dL
  • 20-29: remove from exposure if a repeat in 4 weeks is still 20 or higher20 to under 30 µg/dL
  • 30-79: remove from exposure; prompt medical evaluation advised above 4030 to under 80 µg/dL
  • 80 and above: urgent medical evaluation80 and above µg/dL

CDC clinical guidance action levels for children

  • Below the reference valuebelow 3.5 µg/dL
  • At or above the reference value: find and reduce sources, follow-up testing3.5 to under 20 µg/dL
  • 20-44: full history and exam, contact a specialist20 to under 45 µg/dL
  • 45 and above: detailed neurological exam; hospital admission if symptoms45 and above µg/dL

How common is your level?

NHANES describes the US civilian, non-institutionalized population, not a 'healthy' reference group. People with disease, on medication, fasting or not (except fasting-subsample markers), smokers and so on are all included. A percentile says where a value sits among Americans of that sex and age, not whether it is normal.

How Blood Lead varies with age in the U.S.Shaded: middle 90% and middle 50% of people. Line: the median. µg/dL. Point at any age, or focus the chart and use the arrow keys, to read both sexes in words.

Use the left and right arrow keys to read each age. Shift moves five years.

Reference data derived from CDC/NCHS National Health and Nutrition Examination Survey (NHANES), cycles 2015-2016, 2017-March 2020 (pre-pandemic), August 2021-August 2023. Analysis by bloodtesttracker.com; not endorsed by CDC, NCHS or HHS.

Explore Blood Lead by age and sex: every percentile as a table, with a download.

What can affect your result

  • Recent or ongoing exposure at home, work or through hobbies
  • Lead stored in bone, which can release back into the blood, for example in pregnancy or when bone is turning over quickly
  • Age: children absorb more lead than adults
  • Fingerstick versus venous collection
  • Contamination from skin, dust or tubes that are not trace-element-free
  • Lead on the skin, dust, or a collection tube that is not certified trace-element-free can falsely raise a result. A second sample in a certified tube can confirm it.
  • Fingerstick (capillary) samples pick up contamination more easily than venous draws. A result at or above the reference value should be confirmed on a venous sample.

Any time. Blood lead has a half-life of roughly 40 days, but lead stored in bone can keep releasing into the blood for years, so levels can fall slowly after exposure stops.

When to talk to a clinician

Talk with the clinician who ordered the test if your result is 3.5 µg/dL or higher, and sooner for higher levels. Get urgent care for severe belly pain, repeated vomiting, confusion, weakness or seizures, especially with a high result. Labs phone the ordering clinician right away at 45 µg/dL or higher in a child and 70 µg/dL or higher in an adult (ARUP's limits). If you are pregnant, ask about any result above the reference value.

Questions you could ask

  • How often should I be retested?
  • Where might my lead exposure be coming from, and how can we find out?
  • Should we repeat this on a venous sample, and when?
  • Should other people in my home or workplace, such as children or pregnant people, be tested?

Questions people ask

What counts as a normal blood lead level?

Labs and CDC flag levels of 3.5 µg/dL and higher, because that is higher than the levels of 97.5% of US children. It is a statistical line, not a line between safe and harmful. In 2017-2018 the typical US adult level was under 1 µg/dL.

Why was my fingerstick result high but the venous repeat lower?

Fingerstick samples can pick up lead from skin or dust. CDC advises confirming any fingerstick result at or above the reference value with a venous sample, so the lower result is usually the more reliable one.

How do I convert µg/dL to µmol/L?

Multiply µg/dL by 0.04826, so 3.5 µg/dL is about 0.17 µmol/L. To go the other way, multiply µmol/L by 20.72.

Show the science and sources

Units

  • 1 µg/dL = 1 µg/dL
  • 1 µg/dL = 10 µg/L
  • 1 µg/dL = 0.04826 µmol/L
  • 1 µg/dL = 48.26 nmol/L

Open the Blood Lead unit converter

For clinicians and researchers

Whole-blood lead is typically measured by ICP-MS (ARUP) in K2EDTA or heparin trace-element-free tubes. CDC's blood lead reference value (3.5 µg/dL) is the 97.5th percentile of NHANES 2015-2016 and 2017-2018 results in US children 1-5 years, and CSTE applies the same value for adults. The 2017-2018 NHANES adult typical level was 0.855 µg/dL. Blood half-life is about 40 days (Wani et al. 2015), while bone holds most of the body burden and acts as a long-term source, so a single blood level does not reflect cumulative burden. Kosnett et al. (2007) propose adult laboratory-reporting guidance, with removal from exposure at a single level of 30 µg/dL or higher or two levels of 20 µg/dL or higher four weeks apart, and chelation not indicated unless the level is above 50 µg/dL with significant symptoms. OSHA's general industry lead standard (29 CFR 1910.1025) uses µg per 100 g of whole blood, with written notification and a medical exam at 40 or higher, medical removal at 60 (single result) or an average of 50, and return to work after two consecutive results under 40. CDC's pediatric action levels start at 3.5 µg/dL, with hospital admission advised at 45 µg/dL or higher in a child with symptoms. Capillary results at or above the reference value should be confirmed by a venous sample.

LOINC 5671-3 (primary), 77307-7, 10368-9, 14807-2. Specimen: whole-blood.

Sources

  1. Data and Statistics: Childhood Lead Poisoning Prevention (blood lead reference value), Centers for Disease Control and Prevention (2021)
  2. Blood Lead Level Guidance, CDC / NIOSH
  3. Recommended Actions Based on Blood Lead Level, Centers for Disease Control and Prevention
  4. Recommendations for medical management of adult lead exposure, Environmental Health Perspectives (2007)
  5. Lead, Whole Blood (Venous) (test 0020098), ARUP Laboratories
  6. ARUP Critical Values List (CORP-APPEND-0104A, Rev. 46, April 2026), ARUP Laboratories (2026)
  7. Lead toxicity: a review, Interdisciplinary Toxicology (2015)
  8. Lead (element, PubChem), PubChem (National Library of Medicine)
  9. 1910.1025 - Lead (general industry standard), Occupational Safety and Health Administration

AI-verified against cited sources. Awaiting expert review. Last reviewed 2026-10-03. How we build and check these pages.

Related markers