Ecotoxicological research and related legislation in Serbia

The common nase (Chondrostoma nasus) as an indicator of aquatic pollution and human health risk assessment associated with its consumption

Individuals of common nase were sampled from three waterbodies (Kačer river, Zaovine, and Medjuvršje reservoirs) with different characteristics, types, and levels of anthropogenic pressure. The aims of this study were to determine the concentrations of 26 elements in gills, liver, and muscle using inductively coupled plasma optical emission spectrometry (ICP-OES); determine the concentrations of 17 organochlorine pesticides (OCPs) in muscle tissue using gas chromatography with mass spectrometric detection (GC-MS); compare these findings with fish condition (CF); and conduct human health risk and benefit assessments due to consumption of fish meat using target hazard quotient, target carcinogenic risk factor, Se:Hg molar ratio, Na:K and Ca:Mg ratios, and contribution of elements to human diet. Results indicated that in addition to the fact that the type of ecosystem (lentic vs. lotic) plays an important role in the fate and kinetics of pollutants, the degree of anthropogenic pressure is one of the most important factors of environmental pollution - Zaovine and Medjuvršje reservoirs (both lentic ecosystems) had the lowest and the highest levels of pollution, respectively. CF did not reflect the differences in accumulation of all analyzed elements in nase tissues. None of the 17 analyzed OCPs were detected due to the absence of recent use. Fish muscle was the least affected by metal pollution at all studied localities and could be safely used for consumption. We recorded several benefits for human health when using the nase meat in human diet.

Bioaccumulation of potentially toxic elements in fish species of Serbia: a review

In the first review of potentially toxic elements (PTEs) in fish in water ecosystems in Serbia, 40 studies related to fish contamination with PTEs were identified and evaluated. Studies of concentrations of PTEs in fish tissues covered 28 ecosystems (108 localities). The main studied river ecosystems were the Danube and the Sava, and the Međuvršje reservoir was the most studied standing water ecosystem. Among the most studied fish species were catfish (Silurus glanis), followed by pikeperch (Sander lucioperca), bream (Abramis brama), carp (Cyprinus carpio), and barbel (Barbus barbus). There were 48 "hot spot" sampling sites where concentrations of Hg, Cd, Pb, As, Ni, Fe, and/or Cu exceeded the maximum permitted concentrations (MPCs) prescribed by legislation. Elevated concentrations of these elements were the most detected in fish species sampled in the Danube, Sava, and rivers belonging to the Velika Morava basin. Hg concentrations were the most common above MPC in muscle tissue of species sampled from the Danube and Sava rivers. On the other hand, we can single out the species Vimba bream (Vimba vimba), sampled in Danube River in Zemun near Belgrade, as the safest species for human consumption due to the largest number of elements in fish meat below detection limits. Finally, having in mind all the criteria prescribed by U.S. EPA (2000), we identify and recommend two predatory fish species pikeperch (S. lucioperca) and catfish (S. glanis), and bottom-feeding fish species barbel (B. barbus) as bioindicators of PTEs contamination in Serbian waters.

Ecological risk assessment of metal and hydrocarbon pollution in sediments from an urban tropical estuary: Tijuca lagoon (Rio de Janeiro, Brazil)

Urban tropical lagoons are often impacted by eutrophication, metal, and polycyclic aromatic hydrocarbon (PAH) contamination, but the toxicity of their bottom sediments is still poorly investigated in South America. Aiming to contribute to filling this gap, a sediment quality assessment was conducted in the Tijuca Lagoon (Rio de Janeiro, Brazil) using different lines of evidence (LOEs) including sediment characterization, determination of metals and PAHs, and acute toxicity testing with burrowing amphipods (Tiburonella viscana). Mud and organic matter contents played a crucial role in contaminant distribution along the lagoon. The concentrations of PAH were generally low (mean ΣPAH = 795.42 ± 1146.2 ng/g; n = 23), but a contamination hotspot of light PAH compounds was identified. Such PAHs were mainly pyrolytic, probably related to the deposition of atmospheric pollution, although petrogenic compounds also occur in the lagoon. The data indicated the occurrence of geochemical anomalies of Zn, Cu, Pb, and Hg (mean values = 176.9 ± 91.6, 45.1 ± 21.3, 35.2 ± 15.0, 0.1442 ± 0.0893 mg/kg, respectively; n = 23), probably associated with industrial wastes, garbage deposition, urban runoff, and domestic sewage contributions. The mortality of T. viscana was significant for more than 85% of the samples (mean mortality = 70.3 ± 26.0%; n = 23), but it was not significantly correlated with PAH and metal concentrations. On the other side, domestic sewage contributions and eutrophication seem to play a relevant role in sediment toxicity. Actually, the toxicity observed in the tests seems to be due to the simultaneous influence of multiple toxicants and their combined effects on the organisms. Such stressors may include not only metals, PAH, and eutrophication but also chemicals not evaluated in this study, such as hormones, pharmaceuticals and personal care compounds, perfluorocompounds, detergents, and others.

Allocation of Metals and Trace Elements in Different Tissues of Piscivorous Species Phalacrocorax carbo

Great cormorants (Phalacrocorax carbo) are piscivorous birds, and as apex predators they accumulate high levels of contaminants from the aquatic ecosystems. In the present study, we analyzed distribution of Al, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sr, and Zn in ten tissues (muscle, liver, kidney, spleen, gizzard, heart, skin, lard, breast feathers, and remiges) of the Great cormorants in the Marin Sprud locality, the Danube River, Serbia. Concentrations of elements in tissues were assessed by using inductively coupled plasma optical spectrometry. Linear discriminant analysis indicates that breast feathers and remiges have a high bioaccumulation potential for heavy metals (Cr, Pb, Sr, and Zn). Those tissues had the highest concentrations of lead (Pb) (2.179 ± 0.742; 0628 ± 0.282). Maximum concentrations of mercury (Hg) were detected in liver (30.673 ± 14.081), followed by kidney, for the same element (17.409 ± 5.676), respectively. The overall maximum metal accumulation was observed in breast feathers and remiges, followed by liver and kidney, whereas the minimum values were observed in muscle, skin, and lard. The greatest concentrations of Cr, Ni, Pb, Sr, Zn, and Al were detected in feather tissues. Our study confirms that great cormorant is a good indicator species for monitoring of pollution of river and wetland ecosystems.

Comparison of single extraction procedures and the application of an index for the assessment of heavy metal bioavailability in river sediments

Metals in sediments are present in different chemical forms which affect their ability to transfer. The objective of this body of work was to compare different extraction methods for the bioavailability evaluation of some elements, such as Ba, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, V and Zn from Serbian river sediments. A bioavailability risk assessment index (BRAI) was used for the quantification of heavy metal bioavailability in the sediments. Actual and potential element availability was assessed by single extractions with mild (CaCl₂ and CH₃COONH₄) and acidic (CH₃COOH) extractants and complexing agents (EDTA). Aqua regia extraction was used for the determination of the pseudo-total element content in river sediments. In different single extraction tests, higher extraction of Cd, Cu, Zn and Pb was observed than for the other elements. The results of the single extraction tests revealed that there is a considerable chance of metal leaching from the sediments assessed in this study. When the BRAI was applied, the results showed a high risk of heavy metal bioavailability in Serbian river sediments.

Aquatic sediments pollution estimate using the metal fractionation, secondary phase enrichment factor calculation, and used statistical methods

The sequential extraction procedure of the European Community Bureau of Reference (BCR) was applied for the fractionation of Cd, Cr, Cu, Ni, Pb, Zn, Fe, Mn, and V in the Serbian river sediments. The aim of this paper was to describe a new approach in detection of anthropogenic elements in sediments, related to the Serbian river courses in order to assess their metal contamination. For sediment pollution evaluation, the risk assessment code (RAC) and the secondary phase enrichment factor (KSPEF) were used. Metal fractionation showed more easily mobilized forms predominant for copper, zinc, cadmium, manganese, and lead, which can be one of the indicators for anthropogenic source input. Chromium, nickel, iron, and vanadium found in the residual fraction indicate these metals may be an indicator for natural sources input. Based on RAC classification, results of sediments show no risk (Cr and V), low risk (Ni, Pb, and Fe), medium risk (Cu), high risk (Cd and Zn), and very high risk (Mn). The mean values of KSPEF were Cd > Cu > Zn > Ni > Mn > Pb > Fe > Cr > V, decreasing scale of no to moderately severe enrichment. The sediments were found to be contaminated by heavy metals to various extents, mostly Cd, Cu, and Zn. Research has shown the importance of KSPEF in quantifying degree of metal enrichment in sediments using results of sequential extraction. With the application of this factor, which is not frequently used in the scientific literature, the results obtained with sequential extraction can be used not only for assessment of mobility but also to quantify the metal pollution.

Spatial monitoring of heavy metals in the inland waters of Serbia: a multispecies approach based on commercial fish

The study monitored the contamination of fish muscle tissue by elements Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn at 17 sampling sites, in order to assess the pollution status of the main rivers in Serbia. Of the six commercially important fish species included in the study (pikeperch Sander lucioperca, catfish Silurus glanis, bream Abramis brama, barbel Barbus barbus, chub Squalius cephalus, nase Chondrostoma nasus), the bioconcentration factor (BCF) indicated that benthivore bream and barbel and predatory catfish have the highest tendency toward the accumulation of elements. This study achieved its primary objective and produced a contamination map of Serbia as a basis for further research. The estimated metal pollution index (MPI) showed the Tisa River to be unaffected by direct pollution (with an MPI value of 0.31) and the West Morava and Pek rivers to be affected (with MPI values of 1.92 and 0.73 for the WM1 and WM2 sampling sites and 0.65 for the Pek sampling site). Over the past two decades, Serbia has not expanded its industrial activity, which has resulted in the barely noticeable anthropogenic input of heavy metals in the rivers close to industry, and the main rivers are mostly unaffected and slightly affected. We assumed that pollution by heavy metals in the 1990s was trapped in the sediment, thus showing an increased concentration of elements in the species that live and feed on the bottom. Hg concentrations exceeded the maximum permitted concentrations (MPCs) only in catfish samples (0.62 mg kg(-1)) from the Danube (D3 sampling site) and barbel (0.78 mg kg(-1)) from the West Morava (WM1 sampling site), while Cd concentrations exceeded the MPC in catfish samples (0.09 mg kg(-1)) from the Danube (D1 sampling site) and chub samples (0.1 mg kg(-1)) from the South Morava (SM2 sampling site). The average concentrations of Pb exceeded the MPC in chub and barbel samples (0.32 and 0.82 mg kg(-1), respectively) from the West Morava (WM1 sampling site); chub, barbel, and nase samples (0.35, 0.32, 0.31 mg kg(-1), respectively) from the West Morava (WM2 sampling site); chub and barbel samples (0.35 and 0.3 mg kg(-1), respectively) from the Ibar; chub samples (0.39 mg kg(-1)) from the Drina; chub and barbel samples (0.59 and 0.4 mg kg(-1), respectively) from the Great Timok; and nase samples (0.33 mg kg(-1)) from the Pek. These results demonstrate that there is a need for future studies that would involve similar analyses and focus especially on smaller rivers that have been neglected so far.

Assessment of the environmental significance of nutrients and heavy metal pollution in the river network of Serbia

In this paper, the data for ten water quality variables collected during 2009 at 75 monitoring sites along the river network of Serbia are considered. The results are alarming because 48% of the studied sites were contaminated by Ni, Mn, Pb, As, and nutrients, which are key factors impairing the water quality of the rivers in Serbia. Special attention should be paid to Zn and Cu, listed in the priority toxic pollutants of US EPA for aquatic life protection. The employed Q-model cluster analysis grouped the data into three major pollution zones (low, moderate, and high). Most sites classified as "low pollution zones" (LP) were in the main rivers, whereas those classified as "moderate and high pollution zones" (MP and HP, respectively) were in the large and small tributaries/hydro-system. Principal component analysis/factor analysis (PCA/FA) showed that the dissolved metals and nutrients in the Serbian rivers varied depending on the river, the heterogeneity of the anthropogenic activities in the basins (influenced primarily by industrial wastewater, agricultural activities, and urban runoff pollution), and natural environmental variability, such as geological characteristics. In LP dominated non-point source pollution, such as agricultural and urban runoff, whereas mixed source pollution dominated in the MP and HP zones. These results provide information to be used for developing better pollution control strategies for the river network of Serbia.

Mapping differential elemental accumulation in fish tissues: assessment of metal and trace element concentrations in wels catfish (Silurus glanis) from the Danube River by ICP-MS

Studies of metal accumulation in fish are mainly focused on the muscle tissue, while the metal accumulation patterns in other tissues have been largely neglected. Muscle is not always a good indicator of the whole fish body contamination. Elemental accumulation in many fish tissues and organs and their potential use in monitoring programs have not received proper attention. In the present study, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, and Zn concentrations were assessed by inductively coupled plasma mass spectrometry (ICP-MS) in the following 14 tissues of the wels catfish (Silurus glanis) from the Danube River: muscle, gills, spleen, liver, kidneys, intestine, gizzard, heart, brain, gallbladder, swim bladder, vertebra, operculum, and gonads. A high level of differential elemental accumulation among the studied tissues was observed. The maximum overall metal accumulation was observed in the vertebra, followed by the kidneys and liver, with the metal pollution index (MPI) values of 0.26, 0.25, and 0.24, respectively. The minimum values were observed in the gallbladder, muscle, brain, and swim bladder, with MPI values of 0.03, 0.06, 0.07, and 0.09, respectively. Average metal concentrations in the fish muscle were below the maximum allowed concentrations for human consumption. The mean As, Cd, Pb, Cu, Fe, and Zn concentrations in the muscle were 0.028, 0.001, 0.001, 0.192, 3.966, and 3.969 μg/g wet weight, respectively. We believe that the presented findings could be of interest for the scientific community and freshwater ecosystem managers. There is a need for further research that would assess less studied tissues in different fish species.

Distribution and accumulation of elements (As, Cu, Fe, Hg, Mn, and Zn) in tissues of fish species from different trophic levels in the Danube River at the confluence with the Sava River (Serbia)

Pikeperch (Sander lucioperca), European catfish (Silurus glanis), common carp (Cyprinus carpio), and gobies (Neogobius gymnotrachelus, Neogobius melanostomus) were collected from the Danube River (Belgrade section), and samples of liver, muscle, or whole-body composites (in the case of gobies) were analyzed for As, Cu, Fe, Hg, Mn, and Zn with inductively coupled plasma optical spectrometry to find out if there was a correlation between accumulation of these elements in predatory and prey species, as well as in pairs of species with overlapping diets. Concentrations of all analyzed elements were either higher (Cu, Fe, Mn, Zn) in liver than in muscle, or equal (As, Hg), except for Hg in carp, which was higher in muscle. Mercury concentration in liver and muscle of predators (catfish, pikeperch) was significantly (<10(-4)) higher than in prey fishes (carp and gobies). The results indicate that Hg concentration was biomagnified through the food chain. Concentrations of As, Fe, and Hg in carp liver and gobies whole-body composite were similar, but carp had significantly (<10(-4)) higher values of Zn and Cu in liver. The regression analysis and trendline equations indicate that the concentrations of all tested elements, except for As in liver, and Mn and Fe in muscle, were similar in predatory fish (pikeperch and catfish), on one hand, and in prey fish (carp and gobies), on the other hand. Distinctly high Zn concentration in carp is very common in this species due to its physiology. Concentrations of Hg and Zn were higher than the maximum acceptable concentration due to the high pollution level in this section of the Danube River, accordingly posing a risk for the human consumption of these fish species.

Accumulation of 20 elements in great cormorant (Phalacrocorax carbo) and its main prey, common carp (Cyprinus carpio) and Prussian carp (Carassius gibelio)

In this study, 20 heavy metals and trace elements (Al, As, B, Ba, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Mn, Mo, Ni, Pb, Si, Se, Sr and Zn) were analyzed in different tissues (muscle, liver, intestine, feather and bone) of the great cormorant (Phalacrocorax carbo) and in different tissues (muscle, liver, gills, kidney and gonad) of their main prey (common carp-Cyprinus carpio and Prussian carp-Carassius gibelio) during the nesting season. Cormorant and fish specimens were collected at the Ečka Fishing Farm (Serbia) and from the nearby river. Principal components analysis (PCA) showed that cormorant livers were differentiated from other four tissues by higher concentrations of Hg, Fe, Cu and Mo, feathers by higher concentrations of Al and Si, and bones by higher concentrations of Sr and Mg. Differentiation among the three age classes of cormorants was observed only with regard to elemental concentrations in their feathers: subadult cormorants were differentiated by higher Hg and Zn concentrations, while the adults were separated by higher concentrations of Fe. In comparison with their prey (common carp and Prussian carp) cormorants were differentiated by higher concentrations of Fe, Hg and Cu in the muscle. Toxic mercury concentrations above 4μgg(-1)dw were determined in the liver of juvenile cormorants, as well as in the liver and feathers of subadults. Hg concentrations were significantly correlated among all studied tissues. Cormorant had significantly higher concentrations of Fe and Hg in muscle and liver than two studied fish species.

Characterization of dioxin-like contamination in soil and sediments from the "hot spot" area of petrochemical plant in Pancevo (Serbia)

PURPOSE

Combinatorial bio/chemical approach was applied to investigate dioxin-like contamination of soil and sediment at the petrochemical and organochlorine plant in Pancevo, Serbia, after the destruction of manufacturing facilities that occurred in the spring of 1999 and subsequent remediation actions.

MATERIALS AND METHODS

Soil samples were analyzed for indicator polychlorinated biphenyls (PCBs) by gas chromatography/electron capture detection (GC/ECD). Prioritized soil sample and sediment samples from the waste water channel were analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). Microethoxyresorufin o-deethylase (Micro-EROD) and H4IIE-luciferase bioassays were used for monitoring of dioxin-like compounds (DLC) and for better characterization of dioxin-like activity of soil samples.

RESULTS

Bioanalytical results indicated high dioxin-like activity in one localized soil sample, while the chemical analysis confirmed the presence of large quantities of DLC: 3.0 × 10(5) ng/g d.w. of seven-key PCBs, 8.2 ng/g d.w. of PCDD/Fs, and 3.0 × 10(5) ng/g d.w. of planar and mono-ortho PCBs. In the sediment, contaminant concentrations were in the range 2-8 ng/g d.w. of PCDD/Fs and 9-20 ng/g d.w. of PCBs.

CONCLUSIONS

This study demonstrates the utility of combined application of bioassays and instrumental analysis, especially for developing and transition country which do not have capacity of the expensive instrumental analysis. The results indicate the high contamination of soil in the area of petrochemical plant, and PCDD/Fs contamination of the sediment from the waste water channel originating from the ethylene dichloride production.

Effect-directed analysis of contaminated sediment from the wastewater canal in Pancevo industrial area, Serbia

Wastewater canal (WWC) in Pancevo industrial area in Serbia, whose main environmental receptor is the River Danube, is a well known hot-spot of contamination. WWC sediments have been assessed by UNEP based on chemical target analysis. However, integrative biological data on exposure to hazardous compounds are only provided by the present study which aims at evaluating whether the monitored compounds sufficiently reflect potential hazards and to suggest additional compounds to include in monitoring and hazard assessment by applying effect-directed analysis (EDA) based on arylhydrocarbon receptor-mediated activity and cytotoxicity. Multistep NP-HPLC fractionation provided 18 fractions co-eluting with polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), polycyclic aromatic hydrocarbons (PAHs) and more polar compounds. PAHs fractions exhibited great potencies to induce ethoxyresorufin-o-deethylase (EROD) in H4IIE rat hepatoma cell line expressed as 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TCDD-EQ) (0.1-34.6 x 10(3) pg g(-1)dry weight). Chemical analysis of the most active fractions revealed great concentrations of PAHs (up to 292 x 10(2)ngg(-1) sediment equivalents (SEQ)), methylated PAHs (up to 900 x 10(2) ng g(-1) SEQ), and other alkyl-substituted PAHs. Only minor portions of biologically derived TCDD-EQs could be attributed to monitored PAHs with known relative potencies (REPs). We hypothesize that a major part of the activity is due to non-monitored alkylated and heterocyclic PAHs. Results of the cell cytotoxicity/proliferation assay on H4IIE cell line suggest the presence of sediment pollutants with pronounced potency to disturb cell growth.