Trends in Blood Lead Levels Quantified by ICP-MS: A Reference Laboratory Retrospective Study

Area of Science:

• Environmental Health
• Toxicology
• Public Health

Background:

• Lead exposure can cause serious health issues, including anemia, neurological damage, and developmental and reproductive disorders.
• In 2021, the Centers for Disease Control and Prevention (CDC) revised the blood lead reference value (BLRV) for pediatric patients (1-5 years) from 5 µg/dL to 3.5 µg/dL.
• This revision highlights the need to monitor and manage lead exposure in vulnerable populations.

Purpose of the Study:

• To conduct a retrospective analysis of blood lead concentrations.
• To evaluate the frequency of blood lead concentrations exceeding the new 3.5 µg/dL reference value.
• To assess trends in lead exposure over time.

Main Methods:

• Blood lead concentrations were analyzed using inductively coupled plasma mass spectrometry (ICP-MS) in venous whole blood specimens.
• Zinc protoporphyrin (ZPP) concentrations were retrospectively analyzed in adult patients with corresponding lead results.
• Quantitative hematofluorometry was used for ZPP analysis.

Main Results:

• Retrospective data analysis revealed a decreasing trend in blood lead concentrations for both pediatric and adult patients between 2012 and 2021.
• The study established nonparametric 95% ranges for ZPP in blood (15-43 μg/dL) and the ZPP to heme ratio (26-74 μmol ZPP/mol heme).

Conclusions:

• The reduced blood lead reference value (BLRV) of 3.5 µg/dL provides a critical threshold for identifying elevated lead exposure.
• This lower BLRV enables healthcare providers and public health agencies to implement timely medical and environmental interventions for pediatric lead exposure.
• Continued monitoring and proactive interventions are essential to mitigate the adverse health effects of lead exposure.