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.

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.

The effects of subchronic exposure to terbuthylazine on early developmental stages of common carp.

The aim of this study was to assess the impact of terbuthylazine in surface waters on fish under experimental conditions. Subchronic toxic effects on embryos and larvae of common carp (Cyprinus carpio) were investigated during a 30-day toxicity test. The exposure to terbuthylazin showed no effect on mortality, but significant differences (P < 0.0001) were revealed on weight and growth parameters at concentrations of 520 and 820 µg/L. The inhibition of specific growth rate at concentrations of 520 and 820 µg/L was 14% compared to the control group. No significant negative effects on total body length and body weight were observed at lower concentrations (0.9 and 160 µg/L). The concentrations 520 and 820 µg/L were associated with a delay in development compared to other experimental groups and controls. On the basis of weight and growth rate evaluation and determination of developmental stages, the No Observed Effect Concentration (NOEC) of terbuthylazine was estimated at 160 µg/L and the Lowest Observed Effect Concentration (LOEC) was 520 µg/L. According to these results, the reported environmental concentration of terbuthylazine in Czech rivers does not impact growth, development, morphology, or histology of carp embryos and larvae.

Effect of nitrite on early-life stages of common carp (Cyprinus carpio L.).

A one-month chronic exposure of common carp larvae and embryos to nitrite revealed significant (p < 0.01) differences in total accumulated mortality in fish exposed to 33, 67, and 330 mg/L NO(2)(-) compared with controls. At the highest concentration, all fish died within 8 d of exposure. On the basis of accumulated mortality in the experimental groups, lethal concentrations of nitrite were estimated at 29 d LC50 = 88 mg/L NO(2)(-); lowest-observed-effect concentration (LOEC) = 28 mg/L NO(2)(-); and no-observed-effect concentration (NOEC) = 7 mg/L NO(2)(-). Fulton's condition factor values were significantly lower in fish from all experimental groups compared with controls. By day 12, fish exposed to 33 and 67 mg/L NO(2)(-) had significantly lower mass and total length compared with controls. No significant negative effects of nitrite at the concentrations tested (0.7-330 mg/L NO(2)(-), at 10 mg/L Cl(-)) on hatching or embryo viability were demonstrated, but significant differences in early ontogeny among groups were noted. Fish from all the concentrations showed a dose-related delay in development compared with the controls. Lordosis, kyphosis, scoliosis, and body shortening were observed at all concentrations and in controls, as was yolk sac deformation and edema, eye deformation, and cardiac edema. The incidence of these malformations was positively correlated with nitrite concentration. Histopathology revealed epidermal spongiosis; edema and hyperplasia of the gill epithelium, including hypertrophy and hyperplasia of eosinophilic granular cells (chloride cells); and interstitial edema of skeletal muscle in fish exposed to 67 mg/L NO(2)(-). Similar, but milder, changes were observed at lower nitrite concentrations.

Polyaluminium chloride (PAX-18) - acute toxicity and toxicity for early development stages of common carp (Cyprinus carpio).

OBJECTIVES: The aim of this study is to assess the toxicity of PAX-18 in different developmental stages of common carp (Cyprinus carpio). The preparation PAX-18, with its active ingredient polyaluminium chloride (9% of Al), is a coagulation agent that is used mainly to precipitate phosphates, to prevent surface water eutrophication and incidences of cyanobacteria. It is applied to the water environment and thus could present a potential risk to fish. DESIGN: The toxicity tests were performed on common carp according to OECD (203, 210) methodologies. The acute toxic effect was evaluated for juveniles and the early development stage effect was observed in embryo-larval toxicity tests. The results of the toxicity tests (the number of dead individuals at particular test concentrations) were subjected to a probit analysis using an EKO-TOX 5.2 programme to determine the LC50 values of PAX-18. RESULTS: Acute toxicity value expressed as 96hLC50 was 753.1 +/- 24.3 mg.l-1 (67.8 mg.l-1 Al). Effect on early development stage expressed as the no observed effect concentration was 10 mg.l-1 (0.9 mg.l-1 Al), the lowest observed effect concentration was 50 mg.l-1 (4.5 mg.l-1 Al). No significant effects of the preparation PAX-18 in concentrations of 50 mg.l-1 of PAX-18 and lower were found on hatching, length and weight parameters, morphology and histopathology. CONCLUSION: The lethal concentration of PAX-18 found in acute toxicity tests on common carp was 7-14 times higher than the concentration which is usually applied to water (5-10 mg.l-1 Al). Moreover, fish in eutrophicated water sources are exposed to PAX-18 concentrations corresponding with the lowest observed effect concentration only for a short time, therefore the effect on them can be considered as minimal.

Toxicity of naproxen sodium and its mixture with tramadol hydrochloride on fish early life stages.

Pharmaceuticals occur in water bodies as a consequence of their incomplete removal during waste water treatment processes. The occurence of pharmaceuticals in surface waters as well as their possible impact on aquatic vertebrates have received considerable attention in recent years. However, there is still a lack of informations on the chronic effects of widely used drugs as well as their possible mixture toxicity on non-target aquatic vertebrates as well as their possible mixture toxicity. The aim of this study was to assess the effects of naproxen sodium on early life stages of fish and evaluate its mixture toxicity with tramadol hydrochloride, which was assessed in our earlier study as a single substance. Two embryo-larval toxicity tests with common carp (Cyprinus carpio) were performed according to the OECD guideline 210 (Fish, Early-life Stage Toxicity Test) in order to assess the subchronic toxicity of naproxen sodium and tramadol hydrochlorid-naproxen sodium mixture at the concentrations of 10; 50; 100 and 200 µg/L. These experiments were conducted for 32 days. The subchronic exposure to naproxen sodium and naproxen sodium and tramadol hydrochloride mixture had a strong effect on the early life stages of common carp. Hatching, developmental rate, morphology, histopathology and, in the case of the naproxen sodium and tramadol hydrochloride mixture, mortality were influenced. The bioindicators of oxidative stress were also influenced. The LOEC was determined at 10 µg/L for both naproxen sodium and naproxen sodium and tramadol hydrochloride mixture.

Effects of selected tricyclic antidepressants on early-life stages of common carp (Cyprinus carpio).

Despite the fact that pharmaceuticals occur in surface water in low concentrations, they can still have adverse effect on aquatic biota, because these substances are designed to have a specific mode of action even at low concentrations. To our knowledge, only little is known about the long-term effect of tricyclic antidepressant residues on non-target animals, especially fish. Hence, the aim of this study was to assess the effect of subchronic exposure to selected tricyclic antidepressants - namely, amitriptyline, nortriptyline, and clomipramine and their mixture - on early-life stages of common carp (Cyprinus carpio). Two embryo-larval toxicity tests with common carp were performed, each taking 30 days. For the experiment, three tricyclic antidepressants as well as their mixtures were tested at three different concentrations - 10, 100 and 500 µg/L. Hatching and mortality were recorded twice a day. In addition, samples were taken at regular intervals in order to record developmental stage, morphometric and condition characteristics and morphological anomalies. At the end of the test, additional samples were taken for histopathological examination and also for the determination of antioxidant and biotransformation enzyme activity and lipid peroxidation and protein carbonylation. Long-term exposure resulted in a significant increase in mortality, developmental retardation, morphological anomalies, and pathological changes in brain, heart, and cranial and caudal kidney. In addition, changes in antioxidant enzyme activity as well as increased lipid peroxidation were observed, even at the lowest tested concentrations. Hence, environmentally relevant concentrations of TCAs have the potential to cause harmful effects on early-life stages of fish.

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

The authors performed a toxicity test with ciprofloxacin in fertilized eggs of common carp according to guideline 210 of the Organisation for Economic Co-operation and Development. The tested concentrations were 1 µg L(-1) , 100 µg L(-1) , 500 µg L(-1) , 1000 µg L(-1) , and 3000 µg L(-1) . Accelerated hatching was found in all groups exposed to ciprofloxacin, but significant growth reduction was found only in the group exposed to the highest concentration (3000 µg L(-1) ). Increased numbers of macroscopic morphological anomalies were observed on day 6 of the test (after hatching). The highest numbers of macroscopic morphological anomalies were observed in the groups of free embryos and larvae exposed to ciprofloxacin concentrations of 100 µg L(-1) , 500 µg L(-1) , 1000 µg L(-1) , and 3000 µg L(-1) (20-23% of tested samples). A gradual decrease in glutathione S-transferase activity was detected in all experimental groups exposed to ciprofloxacin, but significant differences (p < 0.01) were found only in groups treated with 500 µg L(-1) and 3000 µg L(-1) . Glutathione peroxidase and catalase exhibited increased activity in most of the tested concentrations (p < 0.01 and <0.05, respectively), whereas decreased glutathione reductase activity was found in the groups exposed to ciprofloxacin concentrations of 500 µg L(-1) and 3000 µg L(-1) (p < 0.05). The concentration of thiobarbituric acid-reactive substances was significantly lower (p < 0.01) in all experimental groups exposed to ciprofloxacin. The lowest-observed-effect concentration of ciprofloxacin was 1 µg L(-1) . These results suggest that hatching, early ontogeny, occurrence of morphological anomalies, antioxidant and biotransformation enzyme activity, and lipid peroxidation in fish can be affected by ciprofloxacin. Environ Toxicol Chem 2016;35:1733-1740. © 2015 SETAC.

The effect of tramadol hydrochloride on early life stages of fish.

The aim of this study was to perform the fish embryo acute toxicity test (FET) on zebrafish (Danio rerio) and the early-life stage toxicity test on common carp (Cyprinus carpio) with tramadol hydrochloride. The FET was performed using the method inspired by the OECD guideline 236. Newly fertilized zebrafish eggs were exposed to tramadol hydrochloride at concentrations of 10; 50; 100 and 200µg/l for a period of 144h. An embryo-larval toxicity test on C. carpio was performed according to OECD guideline 210 also with tramadol hydrochloride at concentrations 10; 50; 100 and 200µg/l for a period of 32 days. Hatching was significantly influenced in both acute and subchronic toxicity assays. Subchronic exposure also influenced early ontogeny, both morphometric and condition characteristics and caused changes in antioxidant enzyme activity. The LOEC value was found to be 10µg/l tramadol hydrochloride.

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.

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 diclofenac on early life stages of common carp (Cyprinus carpio).

Diclofenac residues have been found in surface water, and thus could present a potential risk to aquatic species. The aim of this study was to assess the impact of diclofenac on the mortality, growth, and development of fish, as well as the impact of the drug on histological changes and selected parameters of oxidative stress in the fish. Subchronic toxic effects of diclofenac at concentrations of 0.015, 0.03, 1, and 3mg/L on embryos and larvae of common carp (Cyprinus carpio) were investigated during a 30-day toxicity test under experimental conditions. Exposure to diclofenac at 3mg/L was associated with increased mortality, increased activity of glutathione S-transferase, and decreased activity of glutathione reductase. Decreases in the levels of thiobarbituric-acid-reactive substances were associated with concentrations ≥ 0.03 mg/L. Based on these results a no observed effect concentration (NOEC)=0.015 mg/L and lowest observed effect concentration (LOEC)=0.03 mg/L were generated.

Toxic effects, bioconcentration and depuration of verapamil in the early life stages of common carp (Cyprinus carpio L.).

Verapamil is a pharmaceutical that belongs to a group of calcium channel blockers and is mainly used as a treatment of angina pectoris and arterial hypertension. Verapamil has been detected in aquatic environments in concentrations ranging from ng L(-1) to µg L(-1). In the present study, a series of acute toxicity tests of verapamil on various developmental stages of common carp (Cyprinus carpio) were conducted. As a result, 96hLC50 values of verapamil were estimated at 16.4±9.2, 7.3±1.5 and 4.8±0.2 mg L(-1) for embryos (E5-E9) and common carp larvae L2 and L5, respectively. Lethal concentrations of verapamil decreased with an increase in the age of the fish. Acute exposure to verapamil significantly reduced the heart rate in the embryos and larvae. In an embryo-larval toxicity test (sub-chronic exposure), the bioconcentration, depuration, and toxic effects of verapamil were assessed in common carp. The fish were exposed to verapamil in a concentration of 0.463 (environmentally relevant), 4.63, 46.3 and 463 µg L(-1). Verapamil had no effect on the accumulated mortality, hatching, condition factor, growth or ontogeny of the fish in any of the tested concentrations. In carp exposed to 463 and 46.3 µg L(-1) of verapamil, significantly higher occurrences of malformations and edemas were observed compared to the control. The bioconcentration factor of verapamil in whole fish homogenates ranged between 6.6 and 16.6 and was therefore below the critical value for hazard substances (BCF>500). The half-life and the 95% depuration time for the tested compound were estimated to be 10.2±1.6 days and 44.2±8.6 days, respectively. No effects of verapamil on the studied endpoints were observed at environmentally relevant concentrations.

Associations between fish reproductive cycle and the dynamics of metazoan parasite infection.

The parasite fauna of the stone loach (Barbatula barbatula) was investigated monthly from May to December 2001. Four parasite species were recorded: Gyrodactylus spp. (Monogenea), Tylodelphys clavata (Digenea), Proteocephalus sagittus (Cestoda), and Raphidascaris acus (Nematoda). The changes in the seasonal dynamics of parasite infection were investigated throughout the 8 months. The potential effect of the reproductive investment of the host, measured by gonad mass and gonado-somatic index (GSI), on the parasite infection was tested against the prediction that, during periods of high reproductive investment (beginning of the breeding period or forming gonads after breeding), the fish are more susceptible to parasite infection. Differences between parasite loads between genders were also hypothesized. Seasonal differences in infection were observed for all parasite species studied. The values of GSI showed a pattern of energy accumulation in the pre-reproductive period and at the beginning of breeding, a decrease during breeding, and an increase in the post-breeding period. A similar pattern was observed for parasite abundance, a strong or weak increase in spring and/or autumn and a decrease during summer (July and August). Positive correlations between the abundance of Gyrodactylus spp. and R. acus and both gonad mass and GSI were found in females after eliminating the effect of fish weight. Our results suggest that stone loach females are more susceptible to parasite infection in periods of higher reproductive investment. The main factor determining the infection of T. clavata was fish size. The abundance of P. sagittus was positively correlated with GSI in the total fish sample with no detectable effect of sex or fish weight. The increase in cestode infection in spring supports the hypothesis that the parasite life cycle could by synchronized with the beginning of host reproduction, probably induced by increasing fish hormone levels in the spring.