The assessment of quality of groundwater used for drinking by the population of the Republic of Dagestan, Russia

Aim. Features of the geological structure of the region determine the diversity of the chemical composition of groundwater, represented by springs in the mountainous part of the Republic of Dagestan and artesian waters in the plains. The content of some contaminants in drinking water can affect public health and have negative consequences. The purpose of the work is to conduct a comparative analysis of the regional characteristics of groundwater and substantiate their compliance with hygienic standards for the quality of drinking water. Materials and methods. More than 500 samples of drinking water were taken on the territory of the republic and analysed in the analytical laboratories of the Institute for Problems of Geothermy and Renewable Energy, a branch of the Joint Institute for High Temperatures of the Russian Academy of Sciences and the Institute of Geology of the Dagestan Federal Research Center of the Russian Academy of Sciences. Assessment of carcinogenic risks to public health was carried out in accordance with Guideline 2.1.10.1920‐04.Results. In some mountainous settlements increased values of hardness (up to 14) were revealed, as well as iodide deficiency almost everywhere. In the underground waters of lowland settlements, an increased content of phenols, cadmium and arsenic was revealed.Conclusion. The use of groundwater by the population for drinking purposes in mountainous areas is possible with the preliminary implementation of appropriate water softening measures and preventive measures among the population related to the replenishment of iodine deficiency. The underground waters of the lowland areas do not meet the hygienic requirements for content of arsenic, cadmium and phenols and the carcinogenic risks for the population are at a level unacceptable for the population.