Remote term consequences of acute peat smoke intoxication during puberty in an animal experiment

Introduction. Exposure to peat smoke is a significant environmental risk factor for public health. The period of puberty is characterized by increased vulnerability of the central nervous and reproductive systems to the toxic components of smoke, such as particulate matter (PM_2.5) and carbon monoxide (CO).

The aim of this study was to evaluate the remote effects of exposure to peat smoke on the central nervous system and reproductive system in white rats under conditions simulating real-world concentrations of PM_2.5 and CO.

Materials and Methods. Exposure to peat smoke was performed once for 4 hours during the pubertal period in white rats of both sexes. The mean concentrations of CO and PM_2.5 in the exposure chambers were 29.3 ± 11.1 mg/m³ and 0.39 ± 0.61 mg/m³, respectively. Examination at adulthood included analysis of behavioral responses in the open field test, electroencephalography (EEG) recording, analysis of DNA fragmentation in blood cells, and histological analysis of brain tissue and testes.

Results. A decrease in locomotor and exploratory activity was observed in exposed animals of both sexes. EEG changes were observed only in female white rats and were characterized by a statistically significant decrease in the mean amplitude of the β2 rhythm and an increase in the δ rhythm index compared with the control group. DNA damage in blood cells of exposed animals showed no statistically significant differences when compared with the control. Histological examination of the sensorimotor cortex of the brain and the testes revealed no abnormalities.

Limitations. This study is limited to investigating the remote effect of a single exposure to peat smoke during puberty on the central nervous system and reproductive system of white rats.

Conclusion. Exposure to peat smoke during puberty potentially contributes to the development of depressive-like behavior in adult white rats while preserving normal histological architecture of brain tissue. No gonadotoxic or genotoxic effects were observed.

Compliance with ethical standards. the study was approved by the Local Ethics Committee (LEC) of the East Siberian Institute of Medical and Environmental Research (Protocol of the LEC of the East-Siberian Institute of Medical and Ecological Research No. 7 of 12/15/2023), conducted in accordance with the European Convention for the Protection of Vertebrates Used for Experiments or Other Scientific Purposes (ETS N 123), directive of the European Parliament and the Council Of the European Union 2010/63/EC of 09/22/2010 on the protection of animals used for scientific purposes.

Contribution:
Vokina V.A. – concept and design of the study, conducting the experiment, processing, analyzing and interpreting data, reviewing publications on the topic of the article; writing and design of the article;
Sosedova L.M. – research methodology, writing and formatting of the article, checking of critical content;
Pankova A.A. – conducting the experiment, collecting and initially processing the material, statistical processing of data;
Abramova V.A. – collecting and pre-processing the material, statistical processing of data, preparing illustrations;
Titov E.A. – collecting and pre-processing the material, statistical processing of data, preparing illustrations;
Novikov M.A. – collecting and pre-processing the material, statistical processing of data, preparing illustrations.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version.

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

Funding. The work was carried out according to the research plan within the framework of the state task.

Received: April 13, 2026 / Revised: June 2, 2026 / Accepted: July 1, 2026 / Published: October 20, 2026

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