MONITORING OF THE FLUORIDE AND PHOSPHATE CONTENT IN THE GUSKA RIVER BASIN SOILS

Summary. The article describes the biological and toxic role of Phosphorus and Fluorine. The forms of existence of Fluorine (mobile, immobile) and Phosphorus (mobile, immobile, fixed) in the soil have been established. The mobile form was identified as the most dangerous and prioritized for research due to its easy assimilation by plants. Monitoring of the content of Phosphorus and Fluorine mobile compounds in the Huska River basin soils was carried out in 2021-2022. The authors concluded that the studied area is quite polluted with these compounds, which is caused by the application of phosphate fertilizers. At the same time, there is a decrease in the level of pollution in 2022 compared to 2021. Possible reasons are the binding of Phosphorus and Fluorine mobile compounds into immobile compounds and a decrease in the number of applied fertilizers.

Topicality.Today, the problem of soil contamination with various chemical substances is relevant worldwide, including in Ukraine.Human activity, in particular agro-industrial production, is the main factor that leads to this.Improper or excessive application of fertilizers can cause an excess of some elements in the soil, thereby polluting it.Fluorine and Phosphorus are one of these elements.They enter the soil together as part of phosphate fertilizers, with Phosphorus as the main component and Fluorine as an impurity [1].Phosphorus is an important element for plants, but its excess can lead to serious disturbances in the ecosystem.At the same time, Fluorine is a pollutant even in small quantities.
The goal of the work -monitoring the level of soil contamination of the Huska River basin with fluorides and phosphates.

SECTION XIII. CHEMISTRY, CHEMICAL ENGINEERING AND BIOENGINEERING
Research materials and methods.In the course of the study, 18 soil samples were taken in 2021 and 20 soil samples in 2022.The sampling was carried out in the coastal area of the Huska River and on the territory of adjacent agricultural fields.The content of fluorides and phosphates was measured in the selected samples.Phosphate content was measured by a colorimetric method using a KFK2-MP photoelectrocolorimeter according to the modified Chirikov method [6].The content of fluorides in soil samples was determined by direct potentiometry using a PI-150MA potentiometer and a solidcontact fluoride-selective electrode based on a crystalline LaF 3 membrane.
Results and discussion.Phosphorus is an important macronutrient for human and animal organisms.It is involved in energy exchange processes, is part of cell membranes in the form of phospholipids, and is part of DNA and RNA molecules.Its deficiency in the body can lead to the development of various disorders, including caries, osteoporosis, impaired cognitive functions, slowing of growth and development, and damage to bone tissue [7].Excessive content of Phosphorus in the body also leads to negative consequences: hormonal disorders, the intoxication of the body, and increased risk of hypertension and obesity [8].
Phosphorus is also a very important element for plants, as it plays a role in the processes of growth, respiration, and photosynthesis.It is used by plants in a significant amount, which is why it is necessary to use phosphate fertilizers during the cultivation of agricultural crops.As a result of a lack of Phosphorus, the growth and rate of maturation of plants can slow down, and the yield also decreases [9].At the same time, the excessive content of Phosphorus also has a toxic effect on plants.
In addition, such plants become dangerous for consumption [3].
Fluorine belongs to microelements necessary for humans and animals.The main functions of Fluorine in the body are participation in the formation of bone tissue and tooth enamel.Since Fluorine has quite specific functions in the body, it must be supplied in clearly regulated doses.An excess of Fluorine in the body leads to the development of fluorosis, which manifests itself in damage to teeth and bone tissue.Also, a number of other disorders occur in the body, in particular, in the work of the kidneys, enzymes, and reproductive system [10].
Fluorine is not used in the life process of plants.As it accumulates in the body of the plant, a toxic effect is exerted, which gradually increases.The consequences of this impact on plants are the slowing down of the growth process, damage to chlorophyll, inhibition of photosynthesis, and necrosis [11].
Compounds of Phosphorus and Fluorine in the soil exist in various forms, the main difference of which is solubility and availability to plants.
For Phosphorus, three main forms of existence in the soil can be distinguished: 1) Mobile (inorganic soluble phosphates) 2) Sedentary (phosphates of aluminum, iron, and calcium) 3) Fixed (phosphates of minerals of soil-forming rocks) These forms are in dynamic equilibrium and can gradually transition into one another [12].
Fluorine in the soil is in two main forms: mobile form (soluble fluorides NaF, KF) and immobile (insoluble fluorides АlF 3 , FeF 3 , CaF 2 ).These forms can change into each other, and the ratio between them depends on several factors, in particular, soil pH and the concentration of Ca 2+ , Fe 3+ , and Al 3+ ions in the soil [13].
Among the specified forms of compounds of Fluorine and Phosphorus, the mobile form (soluble fluorides and phosphates) is the most dangerous and СЕКЦІЯ XIII.ХІМІЯ, ХІМІЧНА ТА БІОІНЖЕНЕРІЯ prioritized for determination.This is due to the fact that in this form, fluorides and phosphates are able to spread easily.Also, these forms are well absorbed by plants, entering the food chain.
In the course of the study, conducted in the period from October 2021 to February 2023, the content of fluorides and phosphates in the soils of the Huska River basin was monitored.
The results of measuring the phosphate content in 2021-2022 are presented in Figure 1.