Occupational exposure of bioaerosols to workers of agro-industrial enterprises and related immunological changes

Employees of agro-industrial enterprises in the course of their production activities are exposed to environmental factors: bioaerosols, organic dust, chemicals, unfavorable microclimate, noise and labor process factors.

There are the most unfavorable working conditions in animal husbandry and poultry farming, where high microbiological air pollution of the working area is formed. Prolonged exposure to these factors can lead to the development of immunological changes and increased occupational health risks.

In this regard, conducting a comprehensive hygienic assessment of the working conditions of employees of agro-industrial enterprises and determining their immunological status is one of the urgent scientific and practical tasks of preventive medicine.

The study aims to conduct a comprehensive hygienic assessment of the working conditions of employees of agro-industrial enterprises, determine the level of microbiological air pollution in the work area and study changes in the immunological status under the influence of high microbiological risk factors.

The study included 430 workers employed in livestock farming (n=120), poultry farming (n=110), horse breeding (n=90), and meat-processing enterprises (n=110). Workplace air was assessed for microbiological contamination (CFU/m³), dust concentration, and selected chemical substances. The specialists have measured the parameters of the microclimate, noise and light levels in accordance with current hygiene standards. The humoral immune response was assessed by determining serum concentrations of IgA, IgM, IgG, and IgE, followed by comparative analysis between manufacturing sectors.

The highest microbiological load was identified in poultry enterprises: the total microbial count reached 4533.99 CFU/m³ and was accompanied by elevated concentrations of Staphylococcus spp., members of the Enterobacteriaceae family, and fungi. Livestock and horse-breeding enterprises demonstrated moderate contamination levels, whereas meat-processing plants showed comparatively lower levels. In livestock and horse breeding farms, the level of microbial contamination exceeded sanitary standards by 1.2–1.8 times, while in sausage production enterprises it was 1.3–1.5 times lower than standard values. There was an excess of relative humidity (1.09–1.27 times) and dust concentration (1.18–1.32 times), which increases the adverse effects of production factors. During the warm and cold periods of the year, the air temperature did not meet hygienic standards. The noise level in individual livestock production areas exceeded the standard values by up to 1.1 times.

Immunological analysis revealed sector-specific changes: poultry workers showed increased IgM and IgE, indicating active antigenic and allergic stimulation, while sausage workers showed increased IgA and IgG, reflecting prolonged activation of humoral and mucosal immunity.

The study showed that the working conditions at the enterprises of the agro-industrial complex are characterized by a high microbiological load and the adverse effects of harmful production factors. The most pronounced changes in immunological parameters were detected in poultry and livestock workers, where high levels of microbial contamination of the air were recorded. Increased levels of IgA, IgM, IgG, and IgE indicate chronic antigenic stimulation. Comprehensive hygienic and immunological monitoring is essential for the early detection of occupational risks and the development of preventive measures.

Limitations. The study is limited by the geographical coverage of the surveyed agro-industrial enterprises, the number of employees included, and the lack of dynamic monitoring of immunological parameters in different periods of professional experience. In addition, the assessment was carried out mainly on humoral markers of immunity without in-depth analysis of the cellular component of the immune system.

Contributions:
Ibrokhimov K.I. — development of the research concept and design, formation of methodology, conducting hygienic and microbiological research, data collection and analysis, writing a manuscript;
Iskandarova G.T. — development of epidemiological research design, statistical analysis, data systematization, validation, scientific guidance;
Ermatov N.J. — scientific consulting; improvement of methodological approach, interpretation of research results;
Abdurakhimov B. — participation in data analysis; scientific interpretation of the obtained results;
Nasirdinov M. — data processing, analysis of scientific literature, comparative analysis, final preparation of the manuscript.

Gratitude. The author expresses his sincere gratitude to the employees of agro-industrial enterprises who participated in the study for their assistance and cooperation. The author also expresses special gratitude to his colleagues who provided scientific and organizational support during the research process.

Funding. The study had no funding.

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

Received: 09.04.2026 / Accepted: 13.04.2026 / Published: 27.07.2026

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