No abstract

The Mediterranean blue mussel Mytilus galloprovincialis was used as a pollution level indicator in the Boka Kotorska Bay of the southeastern Adriatic on the Montenegrin coast. The ever-increasing urbanization and industrialization, combined with a poor sewage system, an increase in both marine and inland traffic, as well as insufficient water circulation in the Bay itself have resulted in some level of pollution. Since heavy metals are extremely toxic and do not easily undergo biodecomposition, the results of this study supply valuable information concerning the metal pollution of the marine environment in Boka Kotorska Bay. The concentrations of the investigated metals and nonmetals accumulated in the mussels were determined during the fall of 2007 using Atomic Absorption Spectroscopy (AAS) for Cr, Mn, Co, Ni, Cu, Cd, Hg, Pb, Sn and V, and Energy Dispersive X-ray Fluorescence (ED-XRF) to determine the concentrations of Fe, Zn, Si, P, S, Cl, K and Ca. ED-XRF was also used to determine the levels of non-metals and elements present in high concentrations. Comparing the data from this study in relation to data from other regions for Mytilus galloprovincialis, the mussel sampled from the Boka Kotorska Bay showed a moderate level of pollution.

A number of experiments with ''specific''ground water from the Pannonian Plains (the Republic of Serbia) were conducted in order to define a technological process for drinking water treatment. The ''specificity''of this raw water is reflected in increased pH value and increased concentrations of natural organic matter, ammonia, hydrogen-sulphide and some toxic metals. Removal of natural organic matter by the basic macroporous resins in acid medium (pH 6.6-7.2) ranged up to 92% of the input concentration, and of hydrogen-sulphide up to 60%. The remaining hydrogensulphide, that was not eliminated on the macroporous resin, was completely removed by adsorption on the Filtersorb FMH. The correlation between the concentration of natural organic matter and the UV extinction in raw and processed water, both in the acid and in the alkaline media, was established. The adsorption of natural organic matter on macroporous resins is more efficient in the alkaline medium than in the acid one.

In a sanitation process of drinking water, carbon from the organic matter reacts with chlorine, forming by-products, among which are trihalomethanes (THM). These substances are carriers of mutagenic and can-cerogenic potential and hence should be removed in drinking water treatment. Since the natural organic mat-ters are precursors of THM formation, their removal from the water decreases the concentration of THMs. The THM forming potential is the most reliable indicator in evaluation of organic matter removal during drinking water treatment processes. The results have shown that the reaction producing THMs follows sec-ond order kinetics. The second order rate constant ranged from 0.024 M-1s-1 to 0.065 M-1s-1 at 22 °C and pH = 8.2 for 96 hours. The removal of 78.4% of natural organic matter, by adsorption on anionic exchange res-ins, resulted in the THM forming potential reduction by 63.1%. Various fractions of natural organic matter differ in their reactivity with chlorine, which is important when it comes to selection of the adsorption me-dium in the drinking water treatment processes

The research objective was to investigate the influence of different pipe drainage systems on the concentration and quantity of atrazine leached in drainage water, as well as in surface (0-30 cm) and sub-surface (30-60 cm) soil horizons in the production of agricultural crops on drained Gleyic Podzoluvisol. Investigations involved four different variants of drainpipe spacing (15, 20, 25 and 30 m, i.e. four variants in four repetitions). In a particular trial year, the same crop was grown and the same agricultural practices applied in all trial variants. Maize was grown in the first two trial years and wheat in the last year. Soil and water samples were qualitatively and quantitatively analysed for the presence of atrazine by gas chromatography. Atrazine concentrations in drainage water ranged from those within the limits tolerated for drinking water (out of the growing season) up to 458 ng.dm -3 . Maximum quantity of leached atrazine was recorded in 1998 (0.500 g.ha -1 ), namely, from atrazine application in May 1997 to March 1998 incl., 0.630 g.ha -1 or 0.052% of the initially added quantity was leached. Maximum atrazine concentration in the surface soil layer was recorded in traces or it was not recorded at all (0.013 mg.kg -1 ), whereas no atrazine was recorded in the subsurface layer during the trial period. Analysis of variance produced no statistically significant difference in the atrazine concentration and leaching in drainage water and in the surface soil layer between different variants of pipe drainpipe spacing.