Lead
Understanding Blood Lead Levels
Healthcare providers can measure your blood lead level (BLL) by taking a blood sample. A lab tests the sample for lead. Any amount of lead in the blood means a person was exposed to lead.
Workplace safety and health professionals use BLLs to ensure workers are protected from lead exposure. If a BLL is above normal, healthcare providers decide on the best treatment based on the level of lead in the blood.
BLL Reference Guide
The Occupational Safety and Health Administration (OSHA) and a few state agencies regulate BLLs in workers. Other government agencies and non-government groups offer recommended lead exposure limits.
|
Blood Lead Level
in micrograms per deciliter (µg/dL)
|
Related Regulations and Recommendations
|
|---|---|
| 0.855 µg/dL | In 2017-2018, this was the typical BLL among adults in the United States.1 |
| 3.5 µg/dL | The Council of State and Territorial Epidemiologists’ (CSTE) blood lead reference value is 3.5 µg/dL. This value is used to identify adults and children whose blood lead levels are higher than the 97.5th percentile of adults and children nationwide.2, 3
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The California Department of Public Health (CDPH) recommends that, if the BLL is between 3.5 to 9 µg/dL, the BLL test be repeated every 3 months for adults until their BLL is less than 3.5 µg/dL.4, 5 line spacer
The American College of Occupational and Environmental Medicine (ACOEM) states it is advisable for women who are or may become pregnant to avoid occupational lead exposure that would elevate the BLL greater than or equal to 3.5 µg/dL.7 |
| 5 µg/dL | The ABLES program uses 5 µg/dL to indicate an elevated BLL for surveillance purposes.
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If pregnant, women should not exceed 5 µg/dL. The National Toxicology Program (NTP) concluded that mothers with BLLs even lower than 5 µg/dL can result in reduced fetal growth.6 |
| 10 µg/dL | Below 10µg/dL, the NTP concluded lead increases blood pressure, the risk of hypertension, and the incidence of essential tremor.6
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ACOEM and CDPH recommend repeat BLL tests every two months if a person’s BLL results are between 10 to 19 µg/dL.5, 7 |
| 15 µg/dL | Michigan Occupational Safety and Health Administration (MIOSHA) requires BLL testing every 2 months for employees found to have a BLL of 15 µg/dL or higher. Employees can return to work when they have 2 consecutive BLL tests below 15 µg/dL.
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ACOEM believes workers should not return to work until the BLL is below 15 µg/dL and after a physician assessment of the worker’s health and work status.7 |
| 20 µg/dL | ACOEM and CDPH recommend medical removal if a worker has two consecutive BLLs between 20-29 µg/dL.5, 7
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The American Conference of Governmental Industrial Hygienists (ACGIH®) guideline states that the typical worker can experience a BLL of 20 µg/dL without adverse health effect.8 This guideline is intended for use in the practice of industrial hygiene, but others may wish to use these guidelines as supplements to occupational safety and health programs. |
| 25 µg/dL | ACOEM and CDPH recommend medical removal if a worker has two consecutive BLLs between 20-29 µg/dL.5, 7
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The Occupational Safety and Health Administration (OSHA) considers a BLL of 25 µg/dL as serious and must be handled by inspection. This determination was based on OSHA’s National Emphasis Program (NEP) for Lead, which was released to protect the health and safety of workers in industries determined to pose a higher risk to people and the environment. |
| 30 µg/dL | MIOSHA requires medical removal at 30 µg/dL.
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The Association of Occupational and Environmental Clinics (AOEC), ACOEM, and CDPH recommend that workers be medically removed from work with lead exposure if one BLL exceeds 30 µg/dL.6, 7, 9 line spacer
ACOEM, CDPH, and MIOSHA have issued more stringent and health protective limits than other federal and state-based regulatory groups. |
| 40 µg/dL | If an employee has been medically removed from work based on a previously high BLL, OSHA permits the employee to return to work once 2 consecutive BLLs are measured below 40 µg/dL.10 |
| 50-60 µg/dL | At a BLL of 50-60 µg/dL, OSHA requires medical removal.10
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The employer must remove any employees exposed to lead in the workplace if their BLL is 50 µg/dL or more for workers in construction, or 60 µg/dL or more for workers in general industry. |
References
1 Centers for Disease Control and Prevention (CDC) [2019] Fourth national report on human exposure to environmental chemicals, updated tables, January 2019. Atlanta, GA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention
2 CDC [2023] National Notifiable Diseases Surveillance System (NNDSS), Lead, elevated blood lead level. Atlanta, GA: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention.
3 Council of State and Territorial Epidemiologists (CSTE) [2022], Public health reporting and national notification for elevated blood lead levels. Atlanta, GA.
4 Adopted CSTE Occupational Subcommittee [2021]. Management Guidelines for Blood Lead Levels in Adults.
5 California Department of Public Health [2021]. Health-based guidelines for blood lead levels in adults.
6 National Institute for Environmental Health Services (NIEHS) [2012] National Toxicology Program NTP Monograph: Health effects of low-level lead. Research Triangle Park, NC: U.S. Department of Health and Human Services, National Institutes of Health.
7 Kosnett MJ, Berenji M, Burton AD, et al. [2023]. American College of Occupational and Environmental Medicine (ACOEM) Position Statement: Workplace Health and Safety Necessitates an Update to Occupational Lead Standard Provisions for Medical Removal Protection, Medical Surveillance Triggers, and the Action Level and Permissible Exposure Level for Lead in Workplace Air: ACOEM Response to OSHA.
JOEM Mar 1; 65(3): e170-e176
8 American Conference of Governmental Industrial Hygienists (ACGIH®) [Last revised April 2012] Biological Exposure Indices (BEI®) Introduction Cincinnati, OH. Page visited 2/1/2021.
9 Association of Occupational and Environmental Clinics (AOEC) [2007] Medical management guidelines for lead-exposed adults, revised 4/24/2007. Washington, D.C.
10 OSHA Lead Standards. Washington, DC: U.S. Department of Labor, Occupational Safety and Health Administration.