Methodological support for monitoring technogenic pollution of drinking water with benzene and ethylbenzene

Introduction. Provision of the country population with qualitative drinking water, safety and availability of water resources for all section of the population are among top priorities of social policy and a solid ground for people’s welfare and health.The aim of this study. To develop, optimize, and validate a high-sensitive chromato-mass-spectrometry method for quantification of potentially hazardous chemicals (benzene and ethylbenzene) to be used within activities aimed at control of human-induced contamination in drinking water. Materials and methods. The study was accomplished with using a gas chromatographer of Chromatek-Kristall series with mass selection detector. A standard solution (for benzene 0.0088 µg/cm3 and ethylbenzene 0.0087 µg/cm3) was used to create calibration characteristics of benzene and ethylbenzene; methanol and sodium sulfate were used as reagents.Results. Effective division of benzene and ethylbenzene in the standard sample was achieved at the capillary column ZB-624 for gas chromatography.To fully extract benzene and ethylbenzene from water samples, we tested parameters of a method which could be used to prepare analysis of the equilibrium vapour phase. We investigated influence of temperature and time required for achieving inter-phase equilibrium of benzene and ethylbenzene form a water sample on sensitivity of vapour phase analysis. Highly effective extraction of benzene and ethylbenzene form water samples (97.7–100% respectively) was achieved by using the method for equilibrium vapour phase analysis: sample heating temperature in the vapour feeder is 80 °C; the time required to reach inter-phase equilibrium is 20–30 minutes and 2 grams of sodium sulfate were used in the process.Metrological assessment of the method was carried out in accordance with the requirements of OFS.1.1.0012.15 Validation of analytical methods.Limitations. There are no limitations in these studies.Conclusion. The developed chromatograph mass spectrometric method for monitoring technogenic pollution of drinking water with monocyclic aromatic hydrocarbons (benzene and ethylbenzene) made it possible to expand the range of measured concentrations (from 0.0005 to 0.1 mg/dm3). Contribution: Nurislamova Т.В. – study concept, research advice, relevance and conclusions; Popova N.А. – data collection and analysis, writing the section ‘results’; Maltseva О.А. – relevance writing the sections ‘results and discussion’, ‘conclusion’; Chinko Т.V. – data collection and analysis, writing the section ‘results’. All authors bear full responsibility for the integrity of all parts of the manuscript and approval of its final version.Conflict of interest. The authors declare no conflict of interest.Acknowledgement. The study had no sponsorship.Received: February 07, 2025 / Revised: March 28, 2025 / Accepted: April 8, 2025 / Published: April 30, 2025

benzene, ethylbenzene, drinking water, mass selection detector, vapor-phase chromatography