The most important anthropogenic sources of metals in aquatic ecosystem are certainly wastewaters, that are being discharged untreated or with different levels of purity, so they can cause many changes in the stream / recipient. Heavy metals pass go through biogeochemical process with different retention time in different parts of atmosphere. They do not decompose and have the ability of bioaccumulation, because they are being retained in plants, animals and nature in general. This is an extremely heterogeneous group of elements in terms of biological and ecological effects. Large numbers of metals is essential for proper functioning of the human body and appertain to the group of essential elements. A deficiency of heavy metals on one side can lead to serious symptoms; and on the other, their presence in slightly elevated concentrations can lead to serious illnesses. Their toxicity depends on concentration, and the allowed concentration range varies from metal to metal. Concentrations in which heavy metals can occur depend from source of pollution and features of system in which they are found, so they can range from traces to very high concentrations. Water, as well as air can receive large amounts of pollutants, but beside ability of self-cleaning, some pollutants among which are also heavy metals leads to modification of water quality to that level that it becomes useless for many purposes. From that reason most of European countries have issued maximum allowed amount of heavy metals in industrial waters that are being discharged into natural flow. Some of those values are given in table 1.

The fluoride element is found in the environment and constitutes 0.06 – 0.09 % of the earth’s crust. Fluoride is not found naturally in the air in large quantities. Average concentration of fluoride in air are in the magnitude of 0.5 ng/m3.[1] Fluoride is found more frequently in different sources of water but with higher concentrations in groundwater due to the presence of fluoride-bearing minerals. Average fluoride concentrations in see water are approximately 1.3 mgL-1. Water is vitally important to every aspect of our lives. Water is a risk because of the possible input and transmission of infectious pathogens and parasitic diseases. We use clean water to drink, grow crops for food and operate factories. The most common pollutants in water are chemicals (pesticides, phenols, heavy metals and bacteria). [2] According to the US Environmental Protection Agency, there are 6 groups which cause contamination of drinking water: microorganisms, disinfectants, disinfection byproducts, inorganic chemicals, organic chemicals, radioactive substances. This chapter concerns the importance of continuously monitoring of fluoride and chloride in drinking water by using a fluoride (F-ISE) and chloride (Cl-ISE) ion-selective electrodes. Disinfectants that are added to reduce the number of microorganisms, as well as disinfection byproducts can cause a series of disorders in body (anaemia, impaired function of liver, kidneys, nervous system). Chemical disinfection is economically most favourable when it comes to processing large amounts of water, for the preparation of drinking water and wastewater treatment. That is why this type of disinfection is used almost exclusively in Bosnia and Herzegovina. Chlorine is one of the most widely used disinfectants. Water monitoring information helps us to control pollution level. In this context, our work concerns the determination of fluoride in spring waters from different villages in Tuzla's Canton in Bosnia and Herzegovina, and chloride in drinking tap water from Tuzla and Gradacac as well as one sample of bottled water. Spring water sample from “Tarevcica” is designed by SW1, from “Zatoca” by SW2, from “Sedam vrela” by SW3 and “Toplica” by SW4 while a tap water from Tuzla by TW and tap water from Gradacac by GW and bottled water by FW. The development of potentiometric ion-selective electrode has a wide range of applications in determining ions in water and other mediums. These electrodes are relatively free from interferences and provide a rapid, convenient and non-destructive means of quantitatively determining numerous important anions and cations. [3] The use of ion-selective electrodes

The content of the some ingredients, such as proteins, ash, etc. is important in food products, either they are present in raw materials or in final products. As wheat is also very important food raw material, and flour as the fi nal product of milling, it is important to know their specific physical – chemical properties. The importance of knowing the physical and chemical properties of wheat and flour is due to the determination of quality and kind of fl our which is produced after milling process. In this work, some physical – chemical properties are determined and some comparations of characteristics were performed in both wheat and flour. Characteristics that were observed in this work are moisture content, ash content, protein content, Zeleny sedimentation value, gluten content and water adsorption values. On the base of results obtained in this work, some conclusions are made that could be useful for milling industry.

Agricultural activities directly infl uence the quality of water systems. Investigations showed that application of various agro-technical measures results with the pollution of water streams with heavy metals and other polluters. Increased concentrations of heavy metals result with intake of heavy metals and their transfer to food chains, and for that reason it is necessary to monitor the content of heavy metals regularly. Broad investigations of bio-geochemical cycling of heavy metals in the region of Lake Modrac were performed with combined methodology of determination of heavy metal traces with the estimation of bioavailability, based on the determination of complexing constants for Pb, Cu, Cd and Zn. Monitoring was performed at the locations in the vicinity of agricultural soil. Th e results achieved showed that the content of organic matter in water streams presents the key factor that determines the extent of bioavailability of heavy metal traces in water systems.

Summary Heavy metals are natural ingredients of many plant cultures, and they are increasingly found in the soil as the main group of inorganic contaminants. The consumption of food products, either fresh or processed, with an increased concentration of heavy metals leads to the deposition of these metals in the body, which further leads to a series of consequences in the form of cardiovascular, respiratory, and neurological problems. The behavior of heavy metals in soil and their accumulation by plants depends on many factors, such as soil structure, soil pH value, organic matter content, adsorption complex and other factors. Therefore, the aim of this work is to present the influence of physical and chemical soil parameters on the distribution of heavy metals (Pb(II) and Cd(II)) in plant cultures and to assess the health risk pollution of the mentioned metals in plant cultures (cucumber, pepper, tomato, eggplant).