Effect of salicylic acid on early life stages of common carp (Cyprinus carpio).

Environmental concentrations of pharmaceutical residues are often low; nevertheless, they are designed to have biological effects at low doses. The aim of this study was to assess the effects of salicylic acid on the growth and development of common carp (Cyprinus carpio) early life stages with respect to antioxidant defence enzymes. An embryo-larval toxicity test lasting 34 days was performed according to OECD guidelines 210 (Fish, Early-life Stage Toxicity Test). The tested concentrations were 0.004, 0.04, 0.4, 4 and 20mg/l of salicylic acid. Hatching, early ontogeny, and both morphometric and condition characteristics were significantly influenced by subchronic exposure to salicylic acid. Also, changes in antioxidant enzyme activity and an increase in lipid peroxidation were observed. The LOEC value was found to be 0.004 mg/l salicylic acid. The results of our study confirm the suggestion that subchronic exposure to salicylic acid at environmental concentrations can have significant effects on aquatic vertebrates.

Oxidative stress indices and histopathological effects of the nonsteroidal antiinflammatory drug naproxen in adult zebrafish (Danio rerio).

OBJECTIVES: The aim of this study was to investigate the effects of the nonsteroidal antiinflammatory drug naproxen on adult zebrafish (Danio rerio). METHODS: Three months old zebrafish (Danio rerio) were exposed to naproxen at concentrations of 0.001, 0.1 and 5 mg.L(-1). We focused on the changes in oxidative stress indices during and at the end of the experiment and histopathological examination of tissues after a two week long exposure period. RESULTS: We found that a 3 day long exposure to naproxen causes mild oxidative stress and affects detoxification in zebrafish, which is demonstrated by the increased activity of glutathione peroxidase and glutathione S-transferase at 0.001 and 0.1 mg.L(-1) of naproxen, respectively. After a 7 day long exposure to 0.1 and 5 mg.L(-1), more potent effects on enzymes occur. However, these effects are only short lasting. At the end of the experiment, the activities of the target enzymes recover back to homeostatic baseline levels. Except catalase, which is induced only after a two week long exposure to the environmental concentration of naproxen. Despite the fact that naproxen causes mild oxidative stress in zebrafish, exposure to this drug does not result in lipid peroxidation. Histopathological examination revealed obvious changes to the gills and liver even at exposure to the environmental concentration of naproxen. CONCLUSION: This study demonstrates that the environmental concentration of naproxen can slightly influence both the antioxidant defense system and histopathology of non-target fish.

The effect of the fluoroquinolone norfloxacin on somatic indices and oxidative stress parameters in early stages of common carp (Cyprinus carpio L.).

OBJECTIVES: The aim of this study was to assess the effect of the subchronic exposure of early stages of common carp (Cyprinus carpio L.) to norfloxacin using morphometric data and oxidative stress parameters. METHODS: A subchronic toxicity test was performed on fertilized embryos of common carp according to the OECD Guidelines No. 210. Embryos were exposed to norfloxacin concentrations of 0.0001 (environmental), 0.1, 1.0, 5.0, and 10.0 mg.L(-1) for 34 days. RESULTS: At the end of the test (day 34), significant (p<0.05) stimulation of development was observed in all experimental groups, in contrast to the control. Significantly greater (p<0.01) total body length was also observed in the group exposed to 10.0 mg.L(-1) of norfloxacin compared to the control. A significant increase in the activity of glutathione S-transferase in all carp exposed to norfloxacin concentrations of 0.1 and 1.0 mg.L(-1) (p<0.01), and 5.0 mg.L(-1) (p<0.05) compared to control group was revealed. The activity of glutathione peroxidase was significantly lower (p<0.01) in experimental carp exposed to a norfloxacin concentration of 10.0 mg.L(-1). In experimental carp exposed to a norfloxacin concentration of 0.0001 mg.L(-1), a significant increase (p<0.05) in glutathione reductase activity was found. Significant (p<0.01) decreases in the content of thiobarbituric acid reactive substances in the groups exposed to norfloxacin concentrations of 1.0, 5.0, and 10.0 mg.L(-1) were revealed. CONCLUSION: From the results, we can conclude that norfloxacin has a negative impact on selected biochemical processes related to the production of reactive oxygen species in early-life stages of common carp.

Norfloxacin--toxicity for Zebrafish (Danio rerio) focused on oxidative stress parameters.

The aim of the study was to investigate the effects of subchronic exposure of zebrafish (Danio rerio) to a fluoroquinolone norfloxacin, using selected oxidative stress parameters as a target. Toxicity tests were performed on zebrafish according to the OECD Guidelines number 203 and number 215. In the Subchronic Toxicity Test, a significant (P < 0.01) increase in the activity of glutathione peroxidase, glutathione S-transferase, and catalase was found. In the test, norfloxacin did not affect lipid peroxidation and catalytic activity of glutathione reductase. From the results, we can conclude that norfloxacin has a negative impact on specific biochemical processes connected with the production of reactive oxygen species in fish tested.

Effects of mixture of pharmaceuticals on early life stages of tench (Tinca tinca).

Ubiquitous occurrence of pharmaceuticals in aquatic environment results in concern about potential adverse the effects on nontarget organisms. In water, drugs are present in complex mixtures, in which complicated interactions affect toxicity of single components. The purpose of this study was to examine effect of 35-day-long exposure to mixture of ibuprofen, diclofenac, and carbamazepine on the mortality, growth, early ontogeny, and histopathological changes in tench (Tinca tinca). Early life stage toxicity test was carried out using a modified protocol according to OECD guideline 210. Exposure to mixture of pharmaceuticals at concentration of 60 µg · L(-1) for each substance was associated with significant increase in mortality, as well as significant increase in growth and elevated incidence of malformations. Any of the tested concentrations resulted in histopathological changes of liver, kidney, skin, or gill. After fourteen days of exposure there was short-term delay of development related to increased concentrations of pharmaceuticals in the mixture (2, 20, and 60 µg · L(-1)). Environmentally relevant concentrations (0.02; and 0.2 µg · L(-1)) used in this experiment did not result in toxic impairment of tench.

The effects of subchronic exposure to ciprofloxacin on zebrafish (Danio rerio).

OBJECTIVES: The aim of this study was to assess the impact of ciprofloxacin in Danio rerio on growth, on the development of histopathological changes in selected organs (gills, kidney, liver), and on the activity of some oxidative stress markers during a 28-day toxicity test. METHODS: Juvenile growth tests were performed on D. rerio according to OECD guideline No. 215. Fish at the age of 30 days were exposed for 28 days to a range of concentrations of ciprofloxacin (0.7 µg x L(-1)--environmental concentration, 100, 650, 1100 and 3 000 µg x L(-1)). RESULTS: There were no significant differences between the specific growth rates of fish from the test groups and from the control group. Histopathological examination revealed no pathological changes in organs of fish exposed to any ciprofloxacin concentration. The activity of glutathione S-transferase increased at the ciprofloxacin concentrations of 0.7 and 100 µg x L(-1) compared to the control. A significant decrease in glutathione reductase activity was obtained in fish exposed to ciprofloxacin at 1100 and 3000 µg x L(-1); a significant decrease in glutathione peroxidase activity was also found, but at all tested concentrations except for 100 µg x L(-1). A decrease in the concentration of thiobarbituric acid reactive substances was noted only at 100 µg x L(-1) compared to the control. CONCLUSIONS: According to our results, all tested concentrations of ciprofloxacin, including the environmental concentration, had an influence on oxidative stress markers and detoxifying enzymes in exposed fish, but did not affect fish growth or cause the development of histopathological changes in the fish organism.

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.