Evaluation of immune status indicators in workers engaged in the enrichment of iron‑containing ores

Introduction. Numerous studies demonstrate the impact of harmful occupational factors on the immune system. While these changes are adaptive in the initial stages, prolonged exposure can lead to the development of maladaptive processes, leading to functional impairment of immune cells, which can contribute to the development of pathology.

The study aims to analyze patterns of changes in immune status indicators in workers engaged in the enrichment of iron-containing ores.

Materials and methods. The main group consisted of 95 workers employed at an iron ore beneficiation plant (exposed to occupational factors: crystalline silicon dioxide (class 3.1/3.2), noise (class 3.1/3.2/3.3), general vibration (class 2/3.1), and workload severity (class 3.1)). The comparison group consisted of 85 workers in repair and maintenance occupations (workload severity (class 3.1/3.2)).

The study measured levels of immunoglobulins A, M, G, C3, and C4 complement components, interleukins (IL) 1β, 6, 8, 10, and 18, tumor necrosis factor alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and interferon gamma (IFN-γ).

Results. The workers of the main group had significantly (p<0.05) lower levels of C3 and C4 complement components, IL‑1β, IL-6, IL-10, TNF-α and higher levels of IgG, IL-18, MCP-1, IFN-γ, more often (p=0.017) the levels of IgM below the reference values were observed — in 13.7% than in the comparison group. An increase in the levels of interleukins with work experience was shown: IL-18 in the main group, IL-6 - in both the main and comparison groups. The workers of the main group showed a decrease in IL-10, IFN-γ and an increase in MCP-1 with an increase in the aerosol concentration and an increase in IL-6 and IFN-γ with an increase in the noise level. In the main group, associations of smoking and obesity with the levels of immunoglobulins and proinflammatory cytokines were found.

Limitations. The study is limited to a sample of the surveyed from one mining and processing plant.

Conclusions. The results obtained demonstrate the influence of exposure to a complex of occupational factors at an iron ore enrichment plant on changes in the immune status of workers, which determines the importance of identifying informative immunological indicators for in-depth employee examination to assess the severity of changes.

Ethics. The study was conducted in compliance with Ethical standards for conducting medical research involving humans in accordance with the requirements of the Helsinki Declaration of the World Medical Association. The study was approved by the conclusion of the local Ethics Committee of the Izmerov Research Institute of Occupational Health (protocol of meeting No. 5 dated 08/02/2023).

Contribution:
Khotuleva A.G. — collection of material, data processing, laboratory research, writing, editing;
Kuzmina L.P. — research concept and design, editing;
Khokhlova O.V. — collecting material, data processing, conducting laboratory tests, writing text;
Kolyaskina M.M. — collecting material, conducting laboratory research, editing;
Kislyakova A.A. — collecting material, conducting laboratory research, editing.

Funding. The study had no funding.

Conflict of interests. The authors declare no conflict of interest.

Received: 01.12.2025 / Accepted: 03.12.2025 / Published: 20.12.2025

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