Abstract
Background
Lead exposure among Indigenous Peoples is documented across diverse settings, but the sources driving exposure remain insufficiently synthesized to inform public health action. Many of these populations live in ecologically critical territories and play key roles in biodiversity conservation and climate resilience, making environmental health risks in these settings particularly relevant for global health policy. This study synthesizes evidence on exposure levels and sources to inform prevention.
Methods
We conducted a systematic review following PRISMA 2020 guidelines. Studies reporting blood lead levels (BLL) among Indigenous populations were identified across major databases and grey literature. Data on BLL and reported exposure sources were extracted, categorized, and compared across regions.
Results
Sixty-five studies (1967–2024), representing 121 Indigenous Peoples across 21 countries, were included. The median geometric mean BLL was 5.97 µg/dL, above the CDC reference value (3.5 µg/dL). Weighted pooled means were 7.38 µg/dL in children and 7.78 µg/dL in adults. In studies with comparison groups, BLLs were mostly higher among Indigenous participants. Lead-based ammunition linked to hunting and wild food consumption was the most frequently reported exposure source (pooled mean 5.62 µg/dL), compared with dust (7.85 µg/dL) and battery-related exposure (10.93 µg/dL). Exposure sources clustered regionally, with hunting-related exposure dominant in Arctic and forest settings.
Conclusions
Lead exposure among Indigenous Peoples is shaped by context-specific sources beyond classical industrial sources. Mapping global patterns and quantifying source-specific exposure highlights modifiable points for prevention. These findings support targeted, culturally appropriate interventions, including lead-free alternatives and strengthened surveillance, with implications for policy in settings where environmental change, food systems, and health risks intersect.
Key messages
• Indigenous populations show elevated blood lead levels across regions, with exposure driven by identifiable sources and preventable environmental health risks.
• Mapping source-specific exposure highlights modifiable risks, supporting targeted interventions such as lead-free alternatives and strengthened surveillance in these settings.