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eISSN: 2083-5906
ISSN: 1230-1485
ISSN: 1230-1485
ORIGINAL RESEARCH
Bioaccessibility and Health Risk Assessment
of Inhalable Heavy Metals in Soil from the Bayan
Obo Mining Area, Northern China
1
School of Georesources and Environmental Engineering, Inner Mongolia University of Technology,
Hohhot 010051, China
2
School of Georesources and Environmental Engineering, Shandong University of Technology,
Zibo 255049, Shandong, China
3
Inner Mongolia Geological Survey, Hohhot 010055, China
4
School of Geotechnology, Inner Mongolia University of Technology, Hohhot 010051, China
Submission date: 2025-06-15
Final revision date: 2025-09-03
Acceptance date: 2025-09-07
Online publication date: 2026-02-06
Publication date: 2026-10-23
Corresponding author
De Yao
School of Georesources and Environmental Engineering, Shandong University of Technology, Zibo 255049, Shandong, China
School of Georesources and Environmental Engineering, Shandong University of Technology, Zibo 255049, Shandong, China
Pol. J. Environ. Stud. 2026;35(5):5689-5703
KEYWORDS
soil pollutionbioaccessibilityhealth risk assessmentrare earth elementssimulated epithelial lung fluid
TOPICS
ABSTRACT
Soil contamination caused by mining activities may pose potential risks to human lungs.
This study investigated the pollution levels and inhalable bioaccessibility of selected metal elements in
the soils of Bayan Obo, a representative mining city, and Baotou, an industrial city in China. The human
health risks of metal elements were also evaluated. The results indicated that La, Ce, and Eu exhibited
the highest levels of enrichment, with significant spatial variations. The inhalable bioaccessibility
of the metals followed the order: As>Mn>Ni>Pb≈Zn>Cu>Cr>La>Ce>Eu. Health risk assessment
results indicated that evaluating human health risks based on total metal concentrations rather than
bioaccessible concentrations could not only overestimate the risk of soil metals but, more critically, lead
to misidentification of high-risk pollutants. The measured inhalable bioaccessibility data revealed that
both non-carcinogenic and carcinogenic risks for children and adults were below safety thresholds, with
Mn and As being the primary contributors to non-carcinogenic and carcinogenic risks, respectively.
CONFLICT OF INTEREST
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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