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It is estimated that all over the world there are more than 550 million road vehicles in everyday use. Annually, 1.3 billion used tyres are dismantled from these vehicles due to safety reasons. A small number of these tyres end up reused as second-hand tyres or, after being retreated, as new ones. The rest are end of life tyres which are recycled or used as tire derived fuels under controlled combustion conditions. Modern vehicle tyres are a high-technological product containing, on the average, 85% hydrocarbon, 10-15% steel, as well as some other chemical materials. Tyres belong to high caloric materials, with calorific value of a passenger car tyre of approx. 30.2 MJ/kg being more than of hard coal and comparable to calorific value of petrol-coke. Having this in mind many countries use end of life tyres as safe alternative fuel in cement works or power plants. Undeveloped countries dump end of life tyres on legal and illegal scrap stockpiles. End of life tyres, if deposed correctly, don’t endanger the environment because they are chemically inert. However, since they can easily be burnt there is a real possibility of tyre dump fires, which in effect can lead to harmful products emission that extremely pollute the environment. End of life tyres represent a very important secondary material, which when recycled is transformed into a number of raw materials used in rubber industry, for road construction, sports facilities, residential and business buildings, artificial fish habitats in shallow seas, sea walls, steel production, etc. By the industrial procedures of controlled degradation, which have been uneconomical up till now, gaseous and liquid fuel can be obtained by natural rubber, steel and soot recycling. The countries of the EU, together with Norway and Switzerland, were the world leaders in the field of effective end of life tyre management in the year 2009. Out of 2.62 million tonnes of end of life tyres, 95% were restored or used as energents, and 5% settled on dumps. About 26.000 t of used tyres are collected in Serbia each year. In accordance with adopted legal legislations, up to 30% can be used as tire derived fuels while 70% are being recycled. Serbia belongs to the group of countries which have solved the problem of used tyres in a modern way, and in accordance with EU Legislation practice.

Sulfuric acid is an important industrial and strategic raw material, the production of which is developing on all continents, in many factories in the world and with an annual production of over 160 million tons. On the other hand, the production, transport and usage are very dangerous and demand measures of precaution because the consequences could be catastrophic, and not only at the local level where the accident would happen. Accidents that have been publicly recorded during the last eighteen years (from 1988 till the beginning of 2006) are analyzed in this paper. It is very alarming data that, according to all the recorded accidents, over 1.6 million tons of sulfuric acid were exuded. Although water transport is the safest (only 16.38% of the total amount of accidents) in that way 98.88% of the total amount of sulfuric acid was exuded into the environment. Human factor was the common factor in all the accidents, whether there was enough control of the production process, of reservoirs or transportation tanks or the transport was done by inadequate (old) tanks, or the accidents arose from human factor (inadequate speed, lock of caution etc). The fact is that huge energy, sacrifice and courage were involved in the recovery from accidents where rescue teams and fire brigades showed great courage to prevent real environmental catastrophes and very often they lost their lives during the events. So, the phrase that sulfuric acid is a real "environmental bomb" has become clearer.

Among all alcohol liqueurs, brandies from drupaceous plants are characterized with the highest level of hydro cyanic acid, benzaldehyde and ethylcarbamate. In fruit brandies ethylcarbamate mainly originates from hydro cyanic acid during the processes of alcohol fermentation of crushed fruit and its preservation, distillation and ripening of the brandy. Hydro cyanic acid and benzaldehyde arise from the hydrolysis of amygdaline that is found exist in the heart of fruit stones and seeds, as well as from the hydrolysis of prunasine from the skin and flesh of drupaceous plants. The content of amygdaline and prunazine depends on the type of fruit, which corresponds to the potential content of hydro cyanic acid and benzaldehyde in the brandy that corresponds the stoichiometric ratio 1:3.94. The content of the aldehydes: furfural and benzaldehyde in plum brandy, strong plum brandy, young brandy, of domestic production in the various regions of Serbia were analyzed in this paper.

Phosphogypsum is primarily classified as a heavy waste. The classification of phosphogypsum as dangerous waste may be only maintained under the condition that phosphates with the highest content of radio nuclides are used in the production of H3PO4 by the so called "wet procedure" (Morocco, Florida), which, due to the great quantity of present radio nuclides, causes considerable environmental pollution by radon. The classification of phosphogypsum as a separate category of radioactive waste may be conditionally accepted, because phosphogypsum is not a radioactive waste. All the instructions about the collection, documentation and storage of phosphogypsum so far on disposal sites, and possible transport, also due to non-existing legal recommendations must comply with the classification of phosphogypsum as dangerous waste.

In drinking water, which is consumed daily, either directly, or with food there is a number of compounds, organic or inorganic, depending on the water type, origin and processing. The presence of these substances, due to their daily consumption, may exert a negative influence on human health and even lead to tragic outcomes.A list of inorganic substances and elements that may be found in water is presented in this paper, together with their permitted concentrations (MAC values) and the consequences they may cause, if present in concentrations higher than those permitted by regulations. Special emphasis is placed on heavy metals, because in most instances, they influence the human body unfavourably.

A copper-selective electrode of the coated wire type based on sulphidized copper wire was applied successfully for determining Cu(II) ions by complexometric titration with the disodium salt of EDTA (complexon III). By the formation of internal complex compounds with the Cu(II) ion, the copper concentration in the solution decreases, and all this is followed by a change of potential of the indicator system Cu-DWISE (or Cu-EDWISE)/SCE. At the terminal point of titration, when all the Cu(II) ions are already utilized for the formation of the complex with EDTA, there occurs a steep rise of potential, thus enabling us, through the first or second derivative to note the quantity of copper that is present in the solution. Copper-selective electrode showed a responsivity towards titration with EDTA as a complexing agent, with the absence of "fatigue" due to a great number of repeated measurings. Errors occurring during quantitative measurements were more a characteristic of the overall procedure which involve, because of the impossibility of the complete absence of subjectivity, a constant error, and the reproducibility of the results confirmed this fact. The disodium salt of EDTA appeared as a very efficient titrant in all titrations and with various concentrations ot Cu(II) ions in the solution, with somewhat weaker response at lower concentrations in the solution.

Compounds forming very stable complexes - chelates, have a wide field of application in analytical chemistry. The most famous group of these compounds are complexons. Complexons represent organic polyaminocarbonic acids as for example ethylenediaminetetraacetic acid (EDTA) and its salts. The EDTA molecule has six coordinative sites. It is a hexadentate ligands i.e. it has two binding nitrogen atoms and four oxygen atoms from carboxyl groups and it forms complexes with almost all metal ions. EDTA as a tetraprotonic acid, H4Y disociates through four steps, yielding the ions HsY-, H2Y2-, HY3- and Y4-. Which of the EDTA forms will be encountered in a solution, depends on the pH. Due to the poor solubility of EDTA in pure water, as well as in most organic solvents, the disodium salt of EDTA Na2H2Y-2H2O, under the commercial name complexon III, is utilized for analytical determinations. In water, EDTA forms soluble, stabile chelate complexes with all cations, at the molar ratio 1:1, regardless of the charge of the metal ion. In contrast to other equilibria, which are mainly defined by Le Chatellier's principle, equilibria related to metal-EDTA complex formation are also dependent on the influence of the secondary equilibria of EDTA complex formation. Complexing reactions, which are equilibrium reactions, are simultaneously influenced by the following factors: solution pH and the presence of complexing agents which may also form a stabile complex with metal ions. The secondary reaction influence may be viewed and monitored through conditional stability constants. In the first part of the paper, the reaction of the formation of the Cu2+-ion complex with EDTA is analyzed beginning from the main reaction through various influences of secondary reactions on the complex Cu2+-EDTA: pH effect, complexation effect and hydrolysis effect. The equations are given for conditional stability constants, which include equilibrium reactions under actual conditions.