Background and Objective: Tectonic activity and active faults are conventionally regarded as sources of physical hazards such as earthquakes. However, growing evidence demonstrates that these structures may also function as conduits for deep-seated fluids and gases, creating chronic public-health threats through the release of geogenic contaminants. This review synthesises current scientific literature on the mechanisms by which radon-222 (²²²Rn) and arsenic (As) are mobilised from tectonic structures and the associated health implications.
Review Approach: A critical review was conducted using targeted searches of Scopus, Web of Science, PubMed, and Google Scholar for publications from 2000 to 2026. Studies were selected based on relevance to radon migration in fault zones, arsenic mobilisation in fractured bedrock aquifers, and health risk assessment in tectonically active regions.
Key Findings: Global-scale analysis indicates that plate tectonics exerts first-order control on arsenic distribution, with the majority of major arsenic-contaminated aquifers located in foreland basins of convergent plate margins. A previously published systematic review estimated the radon-attributable lung cancer burden in Iran at approximately 19,400 disability-adjusted life years (DALYs) per year, with a population attributable fraction (PAF) of 10.6% (95% CI: 8.1–13.3%). These estimates should be interpreted in the context of the original study's population, exposure assumptions, and estimation methods. In Hamadan Province, Iran, a study of drinking-water networks reported that 26% of surveyed rural communities had drinking-water results exceeding national and WHO arsenic guidelines; however, this finding alone does not establish a tectonic source. In Qorveh County, Kurdistan Province, a groundwater study reported arsenic concentrations above 10 µg/L across more than 39% of the assessed area during the dry season and 35% during the wet season. These percentages describe the reported spatial extent and should not be interpreted as the proportion of the population exposed. The reported hazard quotient (HQ) 95th percentile was 3.58 for children.
Conclusion and Implications: These findings underscore the necessity of integrating geological data into environmental health monitoring and land-use planning in seismically active regions, including Iran. However, causal links between specific faults and contamination require site-specific evidence.