Physiological and histopathological alterations in Capoeta baliki and Squalius pursakensis after caused by some environmental pollutants.

The present study was aimed to apply physiological and histological biomarkers of pelagic and benthic fish species as biomonitoring of environmental pollutants. Capoeta baliki and Squalius pursakensis were caught from 5 stations in Kirmir Stream (Turkey). After measuring the total length and weight for condition factor analysis, liver, gill, brain, and kidney tissues of fish were taken for histopathological analysis. Dorsal muscles of fish tissues were analyzed for polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs). The mean condition factor of C. baliki and S. pursakensis were 1.14 and 0.97, respectively. It was indicated that the first one was in good condition than the latter one. According to histopathological observations, the alterations in the tissues may be associated with the environmental pollutants' exposure. The total concentration of PAHs of dorsal muscle of C. baliki and S. pursakensis found ranged from 0.915 to 108.421 µg/kg and 0.601 to 675.248 µg/kg, respectively. The highest total concentrations of OCPs were found as 44.16 µg/kg for C. baliki and as 562.12 µg/kg for S. pursakensis. The PCB 28 (10.83 µg/kg), PCB 52 (10.92 µg/kg), PCB 138 (226.24 µg/kg), and the total concentrations of PBDEs were found as 151.74 µg/kg in only S. pursakensis. The result of the concentrations of the investigated pollutants was generally found higher in S. pursakensis which is a higher trophic level than C. baliki. Histopathological alterations were detected as hyperemia in liver, gill, and brain; as hydrophobic degeneration in liver; hyperplasia in gill; and tubular degeneration in kidney tissues of both species. The obtained result of the study shows that the environmental pollutants may affect the physiological and histological status of fish.

In vitro effects of erythromycin and florfenicol on primary cell lines of Unio crassus and Cyprinus carpio.

The ubiquitous use of antibiotics leads exposure of these chemicals on non-target aquatic species, while the toxicity assays for these chemicals are time/labor consuming and expensive. Alternative approaches using primary cell cultures which retain the tissue functionality at its highest form have received global attention compared to cell lines. In the current study, the cytotoxic effects of two commonly used antibiotics from amphenicol (florfenicol) and macrolide (erythromycin) groups were evaluated on primary cell cultures of Unio crassus (mantle, digestive gland, gill, and gonad) and Cyprinus carpio (gill and liver) using MTT and Neutral Red assays. The highest cytotoxic effects were found on the mussel digestive gland and carp liver cells for florfenicol and erythromycin, while the lowest cytotoxic effects were found in mussel mantle cells for both drugs in the MTT test. In the NR test, the highest cytotoxic effects of erythromycin and florfenicol were found in the mussel gill, mantle, gonad, and carp gill cells; the lowest cytotoxic effect of erythromycin was found in the mussel digestive gland, while the lowest effect of florfenicol was found in the carp liver cells. The cytotoxicity of florfenicol was quite low for the carp liver, while the cytotoxicity of erythromycin was quite low in the mussel digestive tract. Thus, it was concluded that cells made from mussel tissues could be used in ecotoxicity tests, and sensitivity may vary according to the tissue.