Organska zagađivala u komunalnim otpadnim vodama Republike Hrvatske

Municipal wastewaters are among the most important sources of waste materials released into the environment. In Croatia, this problem is especially pronounced since only 4.4 % of the total wastewaters are subject to complete mechanical and biological treatment. Beside a limited number of regulated organic contaminants, wastewaters contain an extremely high number of different potentially harmful organic compounds. Comprehensive analyses of Croatian wastewaters using mass spectrometric techniques (GC/ MS, LC/MS) indicated the presence of a large number of different organic compounds with a predominance of two main groups of contaminants: petroleum hydrocarbons and detergent-derived surfactants. Recent investigations of specific organic contaminants in wastewater focused on the determination of so-called emerging contaminants, whose ecotoxicological relevance is based on new types of biological effects and for which water quality criteria have not yet been defined. The main goal of this paper is to make an overview of the present knowledge on the occurrence of different types of organic contaminants in Croatian municipal wastewaters, paying special attention to the emerging contaminants.Komunalne otpadne vode jedan su od najvažnijih oblika unošenja otpadnih tvari u okoliš. U Republici Hrvatskoj taj je problem posebno izražen jer se od ukupne količine otpadnih voda obrađuje samo 12 %, od čega samo 37 % prolazi cjeloviti postupak mehaničkog i biološkog pročišćavanja. Redovito praćenje organskog opterećenja, koje se putem otpadnih voda unosi u prirodne vode, obuhvaća samo manji broj skupnih pokazatelja, kao što su kemijska potrošnja kisika (KPK), biološka potrošnja kisika (BPK), ukupni organski ugljik (TOC) te ukupna i mineralna ulja, hlapljivi fenoli i ukupni tenzidi. Zakonom su propisane i maksimalno dopuštene vrijednosti manjeg broj spojeva iz skupine prioritetnih zagađivala (npr. halogenirani ugljikovodici, ukupni aromatski ugljikovodici), dok su broj i raznovrsnost različitih organskih spojeva u otpadnoj vodi izuzetno veliki. Sveobuhvatne pretrage hrvatskih komunalnih voda masenospektroskopskim tehnikama upozorile su na prisutnost velikog broja specifičnih organskih zagađivala, od kojih su najzastupljeniji naftni ugljikovodici te različiti organski sastojci podrijetlom iz detergenata i sredstava za čišćenje. U novije se vrijeme sve više ističe važnost istraživanja novih tipova zagađivala, čije unošenje u okoliš nije zakonom regulirano, a njihovo štetno djelovanje na okoliš počiva na biološkim mehanizmima koji su tek odnedavno objavljeni u znanstvenoj literaturi. Vrlo istaknuti predstavnici takvog tipa zagađivala su antropogeni spojevi s endokrinim djelovanjem i farmaceutski spojevi. U ovom je radu načinjen pregled postojećeg znanja o pojavljivanju različitih organskih zagađivala u otpadnim vodama hrvatskih gradova, s posebnim naglaskom na rezultate dobivene visokospecifičnim tehnikama

Distribution of Carbohydrates during a Diatom Bloom in the Northern Adriatic

Distribution of carbohydrates was studied in the northern Adriatic during an autumn phytoplankton bloom triggered by strong freshwater discharges from the Po River at the end of the stratification period in October 1993. Total carbohydrates (TCHO) and monosaccharides (MCHO) were determined spectrophotometrically using the MBTH-method, while phytoplankton biomass was followed by determining chlorophyll and carotenoid pigments using the HPLC technique. As indicated by the concomitant increase of chlorophyll α and fucoxanthin, an intensive diatom bloom developed in the upper 5 m of the water column while the chlorophyll biomass was rather low in the layers below 10 m. Total carbohydrate levels varied from 70 μg C/l to 1300 μg C/l with significantly enhanced values in the top 5 m of the water column suggesting a strong link to the diatom biomass. However, it was shown that not only the diatom crop but also the physiological status of the biomass, as reflected by the chlorophyll break-down products, had a strong impact on the TCHO levels. Carbohydrates were found mainly in the form of polysaccharides (up to 92% of TCHO)

Pigment Signatures of Phytoplankton Dynamics in the Northern Adriatic

Seasonal and spatial distribution of chlorophyll and carotenoid pigments were determined over an annual cycle in the central part of the northern Adriatic (transect Po River mouth - Rovinj) by the reversed-phase HPLC technique. The phytoplankton dynamics as reflected in chlorophyll a was affected by two distinct mechanisms: the new production fostered by an intensive nutrient supply to the surface layer by north Italian rivers and regenerated production prevailing in the bottom layer. The most prominent individual accessory pigments were fucoxanthin, 19\u27-hexanoyloxyfucoxanthin, chlorophyll b, peridinin, 19\u27-butanoyloxyfucoxanthin and zeaxanthin, which indicated the presence of diatoms, prymensiophytes, green algae, dinoflagellates, chrysophytes and cyanobacteria, respectively, as the major phytoplankton groups. Phytoplankton blooms, which occur regularly after major freshets in spring and autumn, were dominated by diatoms (fucoxanthin) while, at the beginning of the stratification period, the diatom-dominated population was replaced by a more complex flora dominated by prymnesiophytes (19\u27-hexanoyloxyfucoxanthin). Intensive phytoplankton blooms, triggered by strong freshwater pulses from the Po River, can reach even the oligotrophic coastal waters of western Istria, but are mostly confined to the upper 5 m of the water column

Organic Contaminants in the Jakuševec Landfill and Their Impact on Groundwater Quality

Mnogi deponiji otpada u svijetu i kod nas ne uključuju sustav za prikupljanje procjednih voda te zbog toga predstavljaju velik rizik za okoliš, posebno za podzemne vode. U okviru priprema za program sanacije glavnog deponija otpada grada Zagreba kod Jakuševca, koji je nedavno dovršen, bila su provedena opsežna istraživanja koja su trebala upozoriti na zastupljenost određenih tipova organskih onečišćenja u odloženom otpadu te na intenzitet njihova prodiranja u dublje slojeve tla i u podzemne vode. Detaljnom analizom, uz upotrebu kromatografskih tehnika u kombinaciji sa spektrometrijom masa, identificiran je velik broj pojedinačnih sastojaka. Prema podrijetlu, specifični organski spojevi identificirani u deponiranom otpadu mogu se podijeliti u dvije glavne kategorije: na sastojke koji potječu od biološkog otpada i njegove mikrobiološke transformacije te na sastojke karakteristične za antropogeni otpad. Uočeno je da je transport polarnijih organskih zagađivala procjednim vodama vrlo efikasan što je za posljedicu imalo znatno onečišćenje podzemnih voda u blizini deponija.Landfilling is probably, the most popular disposal method for the management of domestic and industrial waste. Unfortunately, many landfills around the world do not include leachate collection systems and present a considerable risk to the underlying aquifers. There have been numerous reports on groundwater contamination in the vicinity of unprotected landfills, paying particular attention to specific organic contaminants. This problem is especially pronounced in landfills which, in addition to ordinary domestic refuse, contain waste of industrial origin. Jakuševec, the main landfill of the city of Zagreb, belongs to this category. The recently completed remediation programme for Jakuševec included comprehensive investigations with the aim to quantify various organic contaminants in solid waste and establish their possible infiltration into the underlying soils and groundwater. A detailed analyses using chromatographic and mass spectrometric techniques made it possible to identify a number of contaminants. According to their origin, the identified compound classes can be divided into the two main categories: markers of biological waste and its microbial transformation and markers of anthropogenic waste. Our investigations have shown that the composition of organic contaminants changes dramatically during the vertical transport from the solid waste through the unsaturated zone of soil to aquifer sediments, which involves both physicochemical and biotransformation processes. The vertical transport of polar organic contaminants was very efficient and led to a significant contamination of the aquifer in the vicinity of the landfill