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The effect of long-term (30 days) exposure to PCZ (0.2, 50, and 500 microg l(-1)) on intestine-related biochemical markers in rainbow trout was investigated. Multiple biomarkers were measured, including digestive enzymes (proteolytic enzymes and amylase), antioxidant responses (TBARS, CP, SOD, CAT, GR and GPx) and energy metabolic parameters (RNA/DNA ratio, Na(+)-K(+)-ATPase). Exposure to 500 microg l(-1) PCZ led to significantly inhibited (p<0.01) proteolytic enzyme and amylase activity. Activities of the antioxidant enzymes SOD, CAT, and GPx gradually increased at lower PCZ concentrations (0.2 and 50 microg l(-1)). At the highest concentration (500 microg l(-1)), oxidative stress was apparent as significant higher (p<0.05) lipid peroxidation and protein carbonyls, associated with an inhibition of antioxidant enzymes activity. Moreover, energy metabolic parameters (RNA/DNA ratio, Na(+)-K(+)-ATPase) were significantly inhibited (p<0.01) in the intestines of fish exposed to 500 microg l(-1) PCZ, compared with controls. We suggest that long-term exposure to PCZ could result in several responses in intestine-related biochemical markers, which potentially could be used as indicators for monitoring residual PCZ present in the aquatic environment.

We investigated the effect of long-term exposure to carbamazepine (CBZ) on the enzymatic alterations and RNA/DNA ratio in intestine tissue of rainbow trout. Fish were exposed to sublethal concentrations of CBZ (1.0 microg/l, 0.2 or 2.0 mg/l) for 42 days. Digestive enzymes (proteolytic enzymes and amylase) and energy metabolic enzyme (Na(+)-K(+)-ATPase) and antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GPx], and glutathione reductase [GR]) in fish intestine were measured. In addition, intestinal RNA/DNA ratio was determined after 42 days exposure. Carbamazepine exposure at 2.0 mg/l led to significantly inhibited (P < 0.05) activity of Na(+)-K(+)-ATPase. Activities of the antioxidant enzymes SOD, CAT, and GPx in CBZ-treated groups gradually increased at lower concentration of CBZ (1.0 microg/l and 0.2 mg/l), then significantly inhibited (P < 0.05) at 2.0 mg/l. After 42 days, the RNA/DNA ratio in fish intestine was significantly lower (P < 0.05) in groups exposed to CBZ at 2.0 mg/l than in other groups. However, there was no statistical significance (P > 0.05) in the activities of digestive enzymes (proteolytic enzyme and amylase) and GR in all groups. In short, prolonged exposure to CBZ resulted in different responses of various enzymes and significantly lower RNA/DNA ratio in fish intestine. Furthermore, molecular and genetic mechanisms of these physiological responses in fish are not clear, which need to be further studied.

Recently, residual pharmaceuticals are generally recognized as relevant sources of aquatic environmental pollutants. However, the toxicological effects of these contaminants have not been adequately researched. In this study, the chronic toxic effects of carbamazepine (CBZ), an anticonvulsant pharmaceutical commonly present in surface and ground water, on physiological condition status and muscle-based biomarkers of rainbow trout were investigated. Fish were exposed at sublethal concentrations of CBZ (1.0 microg l(-1), 0.2 mg l(-1) and 2.0 mg l(-1)) for 42 days. Compared with the control, there was a significant lower (P < 0.05) condition factor in fish exposed at the highest concentration of CBZ (2.0 mg l(-1)), but the hepatosomatic indices in all groups were not significant changes. At lower CBZ concentration (1.0 microg l(-1), 0.2 mg l(-1)), the antioxidant enzyme activities were induced slightly, except catalase, while at the highest concentration (2.0 mg l(-1)) oxidative stress was apparent as reflected by the significant higher lipid peroxidation and protein carbonyls in the fish muscle, associated with a significant inhibition of antioxidant enzymes activities. Moreover, energy metabolic parameters (RNA-DNA ratio, Na(+)-K(+)-ATPase) were significantly inhibited in muscle of the fish exposed at the highest concentration (2.0 mg l(-1)), compared with the control. In short, CBZ-induced physiological and biochemical responses in fish were reflected in parameters measured in this study, which suggest that these biomarkers could be used as potential indicators for monitoring residual pharmaceuticals present in aquatic environment.

The capacity of the ligninolytic fungus Phanerochaete chrysosporium to degrade a wide variety of environmentally persistent xenobiotics has been largely reported in the literature. Beside other factors, one barrier to a wider use of this bioremediation fungus is the availability of effective formulations that ensure easy preparation, handling and application. In this series of laboratory experiments, we evaluated the efficiency of a granular bioplastic formulation entrapping propagules of P. chrysosporium for removal of four selected pharmaceuticals from wastewater samples. Addition of inoculated granules to samples of the wastewater treatment plant of Bologna significantly increased the removal of the antiviral drug oseltamivir (Tamiflu), and the antibiotics, erythromycin, sulfamethoxazol, and ciprofloxacin. Similar effects were also observed in effluent water. Oseltamivir was the most persistent of the four active substances. After 30d of incubation, approximately two times more oseltamivir was removed in bioremediated wastewater than controls. The highest removal efficiency of the bioplastic formulation was observed with the antibiotic ciprofloxacin. Microbiological DNA-based analysis showed that the bioplastic matrix supported the growth of P. chrysosporium, thus facilitating its adaptation to unusual environment such as wastewater.

Propiconazole (PCZ), a triazole fungicide, is widely present in the aquatic environment, but little is known regarding its chronic toxicity in the fish brain. This study assessed the effects of long-term exposure to PCZ on the antioxidant defense system and Na(+)-K(+)-ATPase activity of rainbow trout brain. Fish were exposed to sublethal concentrations of PCZ (0.2, 50, and 500 microg/l) for 7, 20, and 30 days, respectively. Oxidative stress indices (reactive oxygen species, lipid peroxidation, and carbonyl protein) and antioxidant parameters (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and reduced glutathione) were measured, as well as Na(+)-K(+)-ATPase activity. Adaptive responses to PCZ-induced stress were observed at 7 days. With prolonged exposure, significantly higher levels of oxidative indices were indicative of oxidative stress, as also were the significant inhibition of antioxidant enzyme activity and reduced glutathione content. Na(+)-K(+)-ATPase activity was significantly inhibited after prolonged exposure. Chemometrics of all parameters by principal component analysis, enabled the separation of sampled individuals into four groups with 93.39% of total accumulated variance. A low level of oxidative stress can induce the adaptive responses of the antioxidant defense system, while prolonged exposure to PCZ may lead to serious oxidative damage in fish brain. We suggest that selected biochemical markers in fish brain could be used as potential biomarkers for monitoring residual fungicides present in the aquatic environments.

Recently, residual fungicides are generally recognized as relevant sources of aquatic environmental pollutants. However, the toxicological effects of these contaminants have not been adequately researched. In this study, the chronic effect of PCZ, a triazole-containing fungicide commonly present in aquatic environment, on GSH-related antioxidant system and oxidative stress indices of rainbow trout (Oncorhynchus mykiss) were investigated. Fish were exposed at sub-lethal concentrations of PCZ (0.2, 50 and 500 microg/L) for 7, 20 and 30 days. GSH levels and GSH-related enzyme activities, including GPx, GR and GST, were quantified in three tissues-liver, gill and muscle. The levels of LPO and CP were also measured as makers of oxidative damage. In addition, the correlations of the measured parameters in various tissues were evaluated by using PCA. The results of this study indicate that chronic exposure of PCZ has resulted in different responses in various tissues and the gill was the most sensitive tissue; however, before these parameters are used as potential biomarkers for monitoring residual fungicides in aquatic environment, more detailed experiments in laboratory need to be performed in the future.

In this study, the chronic toxic effects of PCZ, a triazole fungicide commonly present in surface and ground water, on morphological indices, ROS generation and RNA/DNA ratio in liver and white muscle of rainbow trout were investigated. Fish were exposed at sublethal concentrations of PCZ (0.2, 50 and 500mugL(-1)) for 7, 20 and 30d. Compared with the control, there were significant lower CF and HSI in fish exposed at the highest concentration of PCZ. ROS levels in both tissues increased significantly at higher PCZ concentrations (50 and 500mugL(-1)) after 20d and above, as well as in muscle of fish exposed at lowest PCZ concentration (0.2mugL(-1)) after 30d. The hepatic antioxidant enzymes (SOD and CAT) activities were induced significantly at higher concentrations (50, 500mugL(-1)) of PCZ after 20d and at 50mugL(-1) after 30d. Additional, hepatic SOD activity was significantly induced at 0.2mugL(-1) after 30d. Compared with the hepatic antioxidant enzymes activities in fish exposed to 50mugL(-1) of PCZ, there was a decreasing trend in those exposed to 500mugL(-1) after 30d exposure. However, both the antioxidant enzymes activities were significantly inhibited in muscle of fish exposed to 500mugL(-1) PCZ after 30d. Moreover there was significant lower RNA/DNA ratio in both tissues after long-term exposure to higher concentration of PCZ. In short, environmental concentrations of PCZ could not induce obvious impacts on fish, but long-term exposure to higher concentrations of CBZ could affect seriously the health status of fish.

Endocrine-disrupting chemicals (EDC) are manmade or natural chemicals that have the ability to interfere with the endocrine system of animals. They have not been monitored systematically in the Czech Republic. The goal of the present study was the characterization of aquatic environmental pollution from the Brno (Czech Republic) city agglomeration focusing on EDC. Passive sampling devices, as well as semipermeable membrane devices (SPMD) and polar organic chemical integrative samplers (POCIS), were used for the pilot assessment of EDC. They were deployed for 21- to 28-d periods at nine locations in the Svratka and Svitava Rivers, Brno, Czech Republic, including at the inlet and outlet of Brno's wastewater treatment plant. The SPMDs were used to monitor nonpolar compounds such as polychlorinated biphenyls (PCBs), polynuclear aromatic hydrocarbons (PAHs), and organochlorinated pesticides (OCP). The POCIS were used to monitor polar compounds such as pesticides and their metabolites, perfluoro-organic compounds (PFOC), and pharmaceuticals. The passive samplers allowed very low detection limits for soluble (bioavailable) fractions of pollutants. The contribution of PAH, PCB, and HCB in sewage water to pollution of the Svratka River was low. The Brno wastewater treatment plant was identified as the main source of pharmaceuticals, triclosan, methyl triclosan, and some polar pesticides.

In recent years, chemical pollution by the residual pharmaceuticals has been increasingly important issue due to its widely present in the aquatic environment. However, the toxicological effects of residual pharmaceuticals on fish have not been adequately researched. The aim of this work is to investigate the toxic effect of CBZ, an anticonvulsant drug commonly present in aquatic environment, on antioxidant status and Na+-K+-ATPase in gill of rainbow trout exposed to sublethal CBZ (1.0 microg L(-1), 0.2 mg L(-1) and 2.0 mg L(-1)) for 7, 21 and 42 d. After prolonged exposure of CBZ at higher test concentration (0.2 or 2.0 mg L(-1)), oxidative stress was apparent as reflected by the significant higher LPO and CP levels in fish gill, as well as the significant inhibition of antioxidant enzymes activities including SOD, CAT, GR and GPx. Besides, reduced glutathione level and Na+-K+-ATPase activity were significantly lower than those of the control after 42 d of exposure to CBZ at higher test concentration (0.2 or 2.0 mg L(-1)). The results of this study indicate that chronic exposure of CBZ has altered multiple physiological indices in fish gill; however, before those parameters are used as special biomarkers for monitoring residual pharmaceuticals in aquatic environment, more detailed experiments in laboratory need to be performed in the future.