Evaluation of cytotoxicity of peat smoke extract on 3T3-SV40 cell culture

Introduction. In recent decades, wildfires have become more frequent and intense in many fire-prone areas. However, the mechanisms of smoke cytotoxicity at the cellular level are poorly understood. The study of peat smoke extract (PSE) cytotoxicity in fibroblasts is an important model for studying the acute and chronic effects of smoke exposure.

Materials and methods. The cytotoxicity of peat smoke was assessed in a series of in vitro experiments using PSE in 8 dilutions (12.5, 25, 37.5, 50, 62.5, 75, 87.5 and 100%) on 3T3-SV forty mouse embryonic fibroblasts. The cytotoxic effect was assessed after 24-hour incubation by determining the concentration of lactate dehydrogenase (LDH) in the culture medium and performing the MTT test; a morphological assessment of the cells was given.

Results. The results of the study indicate that PSE primarily leads to a decrease in the metabolic activity in fibroblasts, as evidenced by a lower value of the mean inhibitory concentration (IC50) (53.6%) calculated by the MTT test. When assessing the cytotoxic effect of PSE in the LDH test, a sharp decrease in cell viability was observed at its concentration above 62.5%, the IC50 value in this test was 57.7%.

Limitations. The study is limited to the investigation of the cytotoxicity of PSE on the 3T3-SV 40 cell culture using morphological assessment, MTT test and determination of LDH concentration.

Conclusion. As a result of the conducted studies, an assessment of the impact of peat smoke on fibroblasts in vitro was carried out, with the help of which a primary toxicological characteristic of PSE was given.

Compliance with ethical standards. The study was approved by the local ethics committee of the East-Siberian Institute of Medical and Ecological Research (Protocol No.7 of 12/15/2023), conducted in accordance with the European Convention for the Protection of Vertebrate Animals Used for Experiments or for Other Scientific Purposes (ETS N 123), Directive 2010/63/EC of the European Parliament and the Council of 09/22/2010 on the protection of animals used for scientific purposes.

Contribution:
Abramova V.A. – concept and design of research, data collection and processing, statistical data processing, text writing, editing;
Vokina V.A. – concept and design of research, data collection and processing, statistical data processing, text writing;
Sosedova L.M. – concept and design of research, editing.
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: July 20, 2025 / Revised: October 3, 2025 / Accepted: October 15, 2025 / Published: December 19, 2025

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