Scientific substantiation of the indicative safe exposure level of 2-ethylhexanoic acid in the atmospheric air of urban and rural settlements

Introduction. In order to ensure the safety of workers employed in the production of 2-ethylhexanoic acid, its maximum allowable concentration in the air of the working area was scientifically substantiated at the level of 5 mg/m³ (aerosol, hazard class 3) and approved in accordance with the established procedure. For the purpose of production control and supervisory activities, it became necessary to substantiate its hygienic standards in the atmospheric air of urban and rural settlements. Therefore, the aim of the study was to determine the threshold of acute inhalation with the subsequent justification of the indicative safe exposure level.

Materials and methods. Experimental studies on the establishment of the the threshold of acute inhalation action as well as justification of the indicative safe exposure level were carried out in accordance with approved methodological documents (GOST 32542–2013, MU No. 2630–82).

Results. Based on transient changes in physiological, hematological and biochemical parameters of rats after 2 hours inhalation followed by their recovery after 24 hours, it was concluded that the threshold of acute inhalation action is above the maximum achievable concentration level of 2-ethylhexanoic acid (9000 mg/m³). As a hygienic standard in the atmospheric air of urban and rural settlements for 2-ethylhexanoic acid, the of the indicative safe exposure level of 0.05 mg/m³ has been scientifically substantiated using calculation methods.

Conclusion. An indicative safe exposure level for 2-ethylhexanoic acid was scientifically substantiated at the level of 0.05 mg/m³. The recommended value is provided by the analytical control method MUK 4.1.4026–24 “Measurement of the mass concentration of 2-ethylhexanoic acid in the air of the working area, the atmospheric air of urban and rural settlements by capillary gas chromatography with mass spectrometric detection”, developed by the F.F. Erisman Federal Scientific Center of Hygiene of Rospotrebnadzor (limits of determination in the atmospheric air of urban and rural settlements: 0.008–0.08 mg/m³ without dilution; 0.008–4.0 mg/m³, taking into account dilution by 50 times), approved by the Chief State Sanitary Doctor of the Russian Federation A.Yu. Popova on May 31, 2024.

Limitations. Scientific substantiation of the indicative safe exposure level of 2-ethylhexanoic acid in the atmospheric air of urban and rural settlements has been pertormed using only calculation methods.

Compliance with ethical standards. The study was approved by the bioethical commission of the F.F. Erisman Federal Scientific Center of Hygiene of the Rospotrebnadzor.

Author contribution:
Khamidulina Kh.Kh. – concept and design of the study, editing, approval of the final version of the article, responsibility for the integrity of all parts of the article;
Sinitskaya T.A. – text editing;
Tarasova E.V. – concept and design of the study, text writing, editing;
Zamkova I.V. – text writing, editing;
Safandeev V.V. – collection and processing materials for determining the threshold of acute inhalation effect;
Poroshin M.A. – conducting experimental studies to determine the threshold of acute inhalation effect.

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

Acknowledgment. The study was financially supported by JSC Sibur Khimprom.

Received: February 2, 2025 / Accepted: February 25, 2025 / Published: April 30, 2025

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