Levels of Uranium in Soil and Dust and Their Associated Chemical Risks to Human Health: A Systematic Review and Meta-Analysis.

Abstract

Environmental uranium contamination is a growing public health concern driven by mining, nuclear operations, phosphate fertiliser use, and improper waste disposal. These activities raise uranium levels in soil and dust, increasing human exposure and health risks. This systematic review and meta-analysis aimed to synthesise global data on uranium contamination in soil and dust, specifically evaluating carcinogenic and non-carcinogenic health risks across populations. A comprehensive literature search was conducted across Web of Science, Scopus, and PubMed databases for studies published between 2000 and 2025. Two independent reviewers screened titles, abstracts, and full texts, applying the Joanna Briggs Institute critical appraisal criteria for data extraction. Meta-analyses were performed, incorporating pooled estimates where appropriate. Narrative synthesis was applied to data unsuitable for meta-analysis. Eighteen studies from 13 countries met the inclusion criteria. The pooled mean uranium concentration was 3.49 mg/kg in soil and 5.10 mg/kg in dust. Regionally, the WHO South-East Asian Region (SEARO) reported the highest mean soil concentrations (5.26 mg/kg), while the Western Pacific Region recorded the highest dust concentrations (11.69 mg/kg). Non-carcinogenic hazard quotients ranged from 3.1 × 10^-13 (children and adults) to 1.47 (adults), and carcinogenic risks spanned 3.54 × 10^-21 (children) to 2.17 × 10^-9 (adults). Uranium contamination in soil and dust varies by region, with SEARO and the Western Pacific as high-exposure areas. Risk ratios vary, influenced partly by age. Enhancing exposure assessment methods and age-specific risk evaluations is crucial for refining risk characterisation and informing public health interventions in uranium-affected areas.