Persistent organic pollutants in muscle of fish collected from the Nové Mlýny reservoir in Southern Moravia, Czech Republic.

The aim of the present study was to investigate the content of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in muscle tissues of fish, i.e. carp (Cyprinus carpio, L.), bream (Abramis brama, L.) and pike perch (Stizostedion lucioperca, L.) from the middle Nové Mlýny reservoir and compare our results with previous corresponding studies. Samples were analysed by gas chromatography with ion trap tandem mass spectrometry. The highest contents of all pollutants were determined in muscle tissue of bream. The analysis of HCHs showed that ß-HCH was the most abundant. PCB congener 28 was evaluated as the predominant PCB congener. The metabolite p,p'-DDE exhibited the highest concentration of all the monitored metabolites. The monitoring confirmed significantly (P < 0.01) higher concentrations of OCP and PCB in muscle of bream compared to carp and pike perch. The contents of pollutants in our study were found to be lower in comparison to the findings of some previous studies.

Effects of subchronic exposure to N,N-diethyl-m-toluamide on selected biomarkers in common carp (Cyprinus carpio L.).

DEET (N,N-diethyl-m-toluamide) is the most common active ingredient in the insect repellents commonly detected in European groundwater. The aim of this study was to investigate the effect of subchronic DEET exposure on biochemical and haematological parameters, antioxidant enzymes, including catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase, and the amount of thiobarbituric acid reactive substances (TBARS) in common carp (Cyprinus carpio L.). Two specific proinflammatory and anti-inflammatory cytokine genes were selected to assess an immunological status of the fish. Fish were exposed for 28 days to three concentrations of DEET (1.0 µg/L, 0.1 mg/L, and 1.0 mg/L) where 1 µg/L is corresponding to the concentration found in the environment. DEET had a significant (P < 0.05) effect on increased RBC, decreased mean corpuscular volume (MCV), and mean corpuscular haemoglobin value (MCH) compared to control groups in the concentration of 1 mg/L. A significant decline (P < 0.05) in triacylglycerols (TAG) in plasma was found in the concentration of 1 mg/L compared to the control groups. The parameters of oxidative stress in tissues of common carp were weekly affected and immunological parameters were not affected.

Evaluation of biochemical, haematological, and histopathological responses and recovery ability of common carp (Cyprinus carpio L.) after acute exposure to atrazine herbicide.

The aim of study was to evaluate the effect of atrazine exposure (5, 15, 20, and 30 mg·L(-1)) on common carp and the ability of regeneration. During 96 h exposure we observed abnormal behavior in fish exposed to 20 and 30 mg·L(-1). Mortality and histological alterations were noticed only in the group exposed to 30 mg·L(-1). Most experimental groups showed significantly (P < 0.05) lower values of haemoglobin, haematocrit, leukocyte, and lymphocyte and significantly higher values of monocytes, segmented and band neutrophile granulocytes, and also metamyelocytes and myelocytes. A significantly lower (P < 0.05) leukocyte count was also recorded in experimental groups (5 and 15 mg·L(-1)) after recovery period. Statistically significant (P < 0.05) alterations in glucose, total protein, lactate, phosphorus, calcium, and biopterin as well as in activities of ALT, AST, ALP, and LDH were found in most experimental groups. These changes were most apparent in the groups exposed to 20 and 30 mg·L(-1). Most of the indices were found to be restored after the 7-day recovery period with the exception of LDH, ALT, and lactate in the group exposed to 15 mg·L(-1). Our results showed that atrazine exposure had a profound negative influence on selected indices and also on histological changes of common carp.

The effects of atrazine exposure on early life stages of common carp (Cyprinus carpio).

OBJECTIVES: Atrazine and its chloro-s-triazine metabolites are found in surface water and groundwater of the Czech Republic, although their use has been banned since 2005. The objective of the study was to determine the toxic effects of atrazine at an environmentally relevant concentration of atrazine, 0.3 µg.L-1 and at concentrations of 30, 100, and 300 µg.L-1 on morphometric and condition characteristics, development of early life stages, and antioxidant defense enzymes of common carp. METHODS: The embryo-larval toxicity test was performed according to the OECD Guidelines 210 (Fish, Early-life Stage Toxicity Test). RESULTS: Atrazine exposure showed no effect on morphometric and condition characteristics or histology. Exposure at 0.3 µg.L-1 was associated with significantly increased activity of glutathione peroxidase, glutathione S-transferase, superoxide dismutase, and catalase compared to control. Activity of glutathione reductase was slightly higher at a concentration of 0.3 µg.L-1, with significantly lower (p<0.05) activity observed in groups exposed to 30, 100, and 300 µg.L-1 compared to the group exposed to 0.3 µg.L-1. The level of oxidized lipids was slightly higher in groups exposed to atrazine at 100 and 300 µg.L-1 compared to controls. CONCLUSIONS: Atrazine has a significant influence on the biotransformation enzyme and oxidative defense enzymes of early life stages of common carp. The lowest observed effect concentration (LOEC) was 0.3 µg.L-1.

Evaluation of ibuprofen toxicity for zebrafish (Danio rerio) targeting on selected biomarkers of oxidative stress.

OBJECTIVES: The aim of the study was to investigate the effects of subchronic exposure of zebrafish to ibuprofen, using selected oxidative stress parameters as a target. DESIGN: Toxicity tests were performed on Danio rerio according to OECD No. 203 and No. 215. In the growth test, fish were exposed to subletal concentrations of ibuprofen (0.0001, 0.05, 1, 8, and 25 mg.L-1) for 28 days. For the assessment of free radical defense in fish, the catalytic activities of glutathione reductase (GR), glutathione S-transferase (GST), glutathione peroxidase (GPx), and catalase (CAT), as well as the concentration of malondialdehyde (MDA) were measured. RESULTS: Ibuprofen did not affect the activity of glutathione reductase and catalase. A significant (p<0.01) increase in the activity of glutathione peroxidase was found, which was proved dose-dependent (10.58 nmol NADPH per min per mg protein in the control and 20.53, 26.36, 26.89, and 45.87 nmol NADPH per min per mg protein in the ibuprofen concentrations of 0.5, 1, 8, and 25 mg.L-1. An increased (p<0.05) activity of glutathione S-transferase in the highest concentration was found compared to control. Malondialdehyde levels were found significantly (p<0.01) decreased from control in the concentrations of 0.0001 and 8 mg.L-1, but no dose-dependence was found. CONCLUSION: The results suggest that ibuprofen causes the increase in the activity of some antioxidative and biotransformation enzymes in zebrafish (GPx and GST). We also found a significant decrease in lipid peroxidation in the concentrations of 0.0001 and 8 mg.L-1 compared to control.

Biochemical markers for the assessment of pollution of selected small streams in the Czech Republic.

OBJECTIVES: The objective of the presented study was to investigate levels of the most important biochemical markers in fish which were caught upstream and downstream from sites near waste water treatment plants situated at 3 selected small streams of the Czech Republic. Organic pollutants and mercury were determined in muscle tissue of fish for complex assessment. DESIGN: Levels of biochemical markers (cytochrome P450 (CYP450), ethoxyresorufin-O-deethylase (EROD), glutathione S-transferase (GST), vitellogenin (VTG)) were measured in selected tissues (liver, plasma, brain, gill and kidney) samples of brown trout. The concentrations of persistent organic pollutants (POPs) and mercury were determined in muscle samples. RESULTS: Significantly higher levels of biochemical markers (EROD, GST, VTG) were measured downstream from waste water treatment plant (WWTP) in Vlachovo Brezí (the small Libotýnský brook). Values of biochemical markers at the other localities Cerný brook and Moravice River were measured downstream from WWTP consistently or slightly lower with values of upstream. The values of POPs and mercury were in all monitored sites higher upstream compared with downstream from WWTP. The highest values of POPs and mercury were found on Cerný brook in Bruntál (more industrial and agricultural activity). CONCLUSION: The highest occurrence of selected POPs and mercury was generally upstream suggesting that small WWTP are able to partially remove these substances in those locations. But finding higher values of biochemical markers in downstream shows that there are many other substances endocrine disrupting chemicals (EDCs) that WWTP are unable to remove.

Organochlorine compound residues in muscle of wild boar (Sus scrofa L.) and red deer (Cervus elaphus L.): effects of age and sex.

Twenty-six organochlorine pesticides and 7 polychlorinated biphenyls were measured in muscle of wild boar and red deer from the Czech Republic. The concentration of DDT and its metabolites was higher (p < 0.01) in wild boar than in red deer, while PCBs and HCH were higher (p < 0.01) in red deer than in wild boar. The concentrations of DDT and its metabolites, hexachlorobenzene and hexachlorocyclohexane isomers were higher (p < 0.05) in juvenile wild boar than in adults. PCB 153 and p,p'-DDE were the most prominent pollutants in both red deer and wild boar.

The effects of subchronic exposure to metribuzin on Danio rerio.

The aim of this study was to assess the impact of metribuzin in surface waters on fish under experimental conditions. The effects of subchronic exposure to metribuzin on fish growth and the development of histopathological changes in selected organs (gill, kidney, liver) and on activity of some biochemical markers (CYP450, EROD) in Danio rerio were investigated during a 28-day toxicity test. Juvenile growth tests were performed on D. rerio according to OECD method number 215. Fish at an initial age of 30 days were exposed to a range of metribuzin concentrations (1.5, 5, 16, 33, and 53 mg L⁻¹). Exposure to metribuzin at 53 mg L⁻¹ was associated with increased mortality. Negative effects with regard to total body weight, length, and the inhibition of specific growth rate were induced at concentrations of 33 and 53 mg L⁻¹. Histopathological examination revealed pathological lesions in the liver in pesticide-exposed fish only at the highest concentration of 53 mg L⁻¹ of metribuzin. Based on the results of growth rate, biochemical markers (CYP450, EROD), and histopathological examination, the lowest observed effect concentration (LOEC) value was 33 mg L⁻¹ and the no observed effect concentration (NOEC) value was 16 mg L⁻¹.

The effects of subchronic exposure to terbuthylazine on zebrafish.

OBJECTIVES: Terbuthylazine belongs to the group of symmetrical triazine herbicides used extensively in agriculture and non-agricultural sites, primarily to control broadleaf and some grassy weeds that have become ubiquitous contaminants of the environment. The aim of this study was to assess the impact of terbuthylazine in surface waters on fish under experimental conditions. The effects of subchronic exposure to terbuthylazine on fish growth and the development of histopathological changes in selected organs (gill, kidney, liver), and on the activity of some biochemical parameters - glutathione S-transferase (GST), glutathione reductase (GR) and glutathione peroxidase (GPx) and on the concentration of thiobarbituric acid reactive substances (TBARS) in Danio rerio were investigated during a 28 day toxicity test. METHODS: Juvenile growth tests were performed on Danio rerio according to OECD guideline No. 215. Fish at the age of 30 days were exposed for 28 days to a range of sublethal concentrations of terbuthylazine (0.55 - environmental concentration, 150, 400, 700 and 1000 µg/L). RESULTS: There were no significant differences (p<0.05) between the specific growth rates (r) of the test groups and control group. Histopathological examination revealed pathological changes only in the liver in fish exposed to terbuthylazine at concentrations of 700 and 1000 µg/L. Significant differences (p<0.05) in activities of biochemical markers were found in GST (400, 700 and 1000 µg/L), GR (700 and 1000 µg/L), significant differences (p<0.05) of TBARS concentration were found at 1000 µg/L. CONCLUSIONS: Based on the results of growth rate, the histopathological examination of selected organs, and the results of biochemical parameters, it was found that the environmental concentration of terbuthylazine did not have any effects on juvenile D. rerio. The values of NOEC and LOEC for terbuthylazine for juvenile D. rerio were 150 µg/L and 400 µg/L.