Lead toxicity

Lead toxicity occurs after occupational or home exposure to lead. There is no threshold level for toxicity.

Anyone at risk of lead exposure requires screening with regular blood lead measurements. There is no 'normal' level, and interventions are initiated at the first sign of increased exposure.

Lead toxicity causes neurodevelopmental dysfunction in children and a range of cardiovascular, renal, neurological, and haematological dysfunctions in adults.

The mainstay of treatment is removal of the source. Chelation therapy is given for blood levels ≥2.2 micromoles/L (≥45 micrograms/dL) in a child or >3.4 micromoles/L (>70 micrograms/dL) in an adult, or if the patient is symptomatic.

Acute lead encephalopathy is a medical emergency requiring aggressive chelation therapy in an intensive care setting.

Acute symptoms resolve with treatment, but neurological impairments and cardiovascular toxicities are irreversible.

Lead resides in bone for decades after exposure has ceased; all patients require long-term monitoring.

Lead toxicity is a multisystem disease produced by inhalation or ingestion of lead. It produces neurodevelopmental dysfunction in children and a range of cardiovascular, renal, neurological, and haematological dysfunctions in adults. Any detectable lead level is consistent with exposure to lead.

The US Centers for Disease Control and Prevention (CDC) employs a blood lead reference value of ≥0.17 micromoles/L (3.5 micrograms/dL) to identify children with blood lead levels greater than most other children’s levels.[1]Centers for Disease Control and Prevention (CDC). Blood lead levels in children. Childhood lead poisoning prevention program. February 2022 [internet publication]. https://www.cdc.gov/nceh/lead/prevention/blood-lead-levels.htm A case definition for an elevated blood lead level in an adult (person ≥16 years of age) is ≥0.24 micromoles/L (5 micrograms/dL).[2]Centers for Disease Control and Prevention (CDC). Understanding blood lead levels. Adult Blood Lead Epidemiology and Surveillance (ABLES). National Institute for Occupational Safety and Health (NIOSH) workplace safety & health topics. Apr 2023 [internet publication]. https://www.cdc.gov/niosh/topics/lead/referencebloodlevelsforadults.html [3]Centers for Disease Control and Prevention. Lead, elevated blood levels 2016 case definition. April 2021 [internet publication]. https://ndc.services.cdc.gov/case-definitions/lead-elevated-blood-levels-2016 In an adult, the US Occupational Safety and Health Administration considers a blood lead level of ≥1.2 micromoles/L (25 micrograms/dL) to be serious, requiring inspection.[3]Centers for Disease Control and Prevention. Lead, elevated blood levels 2016 case definition. April 2021 [internet publication]. https://ndc.services.cdc.gov/case-definitions/lead-elevated-blood-levels-2016