Micronuclei and dyskaryosis of erythrocytes and oxidative stress response with endosulfan exposure in topmouth gudgeon Pseudorasbora parva

Comparative metal accumulation and toxicogenetic damage induction in three neotropical fish species with distinct foraging habits and feeding preferences

Environmental pollutants affect fish species differently because their routes of exposure make them more critical to a specific group regarding foraging habits or food preferences. However, the association between local problems and environmental conditions makes a particular species more suitable for use in monitoring programs. Thus, this study compared muscle accumulation of metals (Al, Ba, Cr, Cu, Fe, Mn, Ti and Zn) and toxicogenetic damage to three neotropical species from the Itapemirim River Basin (Brazil) with distinct foraging habits and feeding preferences: Geophagus brasiliensis (benthopelagic - omnivorous); Harttia sp. (benthic - detritivorous); and Leporinus copellandii (pelagic - omnivorous). There was seasonal influence on muscle metal concentrations: Ba and Mn concentrations in G. brasiliensis, Cr in Harttia sp. and Zn, Al and Fe in L. copellandii increased during the rainy season. G. brasiliensis was the most sensitive species, since it had a statistically higher prevalence of erythrocytic nuclear abnormalities, which was influenced by seasonality. This result might be an effect of its benthopelagic habits, which favors contact with a larger group of contaminants due to its interaction with both water column and sediment. The present study showed the differential sensitivity of fish species and that the combination of chemical analysis of pollutants with evaluation of toxicogenetic responses helps to choose the best species for field studies.

Extending international toxicity testing guidance to middle eastern test species

The Arabian Gulf is a dynamic environment with unique habitats located in the Middle East. The inhabitants of this ecosystem have historically been understudied and a lack of reliable toxicity data exists to benchmark their sensitivities. Current international testing guidelines (i.e. Organization for Economic Co-Operation and Development (OECD), International Standard Organization (ISO), Environmental Protection Agency (EPA), etc.) do not reference relevant species for this region of the world. This research focuses on developing standard test conditions for relevant test organisms indigenous to the Middle East region while maintaining general agreement with international testing guidelines. A copepod, cyanobacteria and juvenile killifish were selected as local test organisms to perform acute exposures to 4 Aromatic Hydrocarbons (AHs) ranging in log K_OW from 3.88-5.19, 1-methylnaphthalene, phenanthrene, biphenyl and octahydrophenanthrene. Acute test durations were 48, 72 and 96 h and generally followed ISO 14669, OECD 201 and 203 for the copepod, algae and killifish respectively. To deliver and maintain controlled exposure concentrations, a passive dosing (PD) format was employed. PD effectively maintained aqueous exposure concentration of the AHs tested over the test duration. Effects data were comparable to literature values for similar taxonomic groupings. Critical target lipid body burden's for test species used were calculated and found to be in agreement with those predicted by the Target Lipid Model.

Genoprotective Effect of New Triazine Derivatives in Endosulfan Mediated Toxicity, an In vivo and In vitro Study

Background:

Recently, we reported synthesis and neuroprotective activity of some new 1,2,4-triazine derivatives against H2O2 and β-amyloid toxicity in two neurotic cell lines, SHSY5Y and PC12.

Methods:

The promising results obtained prompted us to further study on these potent neuroprotective agents. In the current study, in vivo anti-inflammatory effect and also genoprotective activity of these compounds in endosulfan-mediated toxicity were investigated. Compounds RT and SMO exhibited high anti-inflammatory effect at 3 and 4 hours after injection in 20 mg/kg, and were even more effective than Indomethacin (20 mg/kg).

Results:

Interestingly, compound SMO in 200 &#181;M was the best compound in reducing micronuclei significantly (P value <0.0001) in lymphocytes treated with endosulfan compared to control group.

Conclusion:

Herein, we report SMO as a genoprotective agent and a new drug candidate for endosulfan mediated toxicity.

Embryonic and larval development of the topmouth gudgeon, Pseudorasbora parva (Teleostei: Cyprinidae)

The topmouth gudgeon, Pseudorasboraparva (Temminck &amp; Schlegel, 1842), is a small cyprinid fish that inhabits the littoral zones of freshwater habitats throughout Asia and Europe. It is regarded as an invasive species in Europe, but in its native range, in China, as food and as an environmental bio-indicator. In this study, the embryonic and larval development of P.parva was investigated for the first time. The eggs of P.parva are transparent, adhesive and elliptical. The mean size of fertilized eggs was (1.63×1.31) ± 0.04 mm. From fertilization to hatching, embryonic development could be divided into eight stages and 34 phases, and the incubation period lasted for 109.25 hours at 24 ± 1 °C. Newly hatched larvae were 4.1 ± 3 mm in length, and the yolk absorption was completed within six days after hatching. The first and second swim bladders formed at the third and ninth day, respectively. The pectoral fin formed before the hatching stage, followed by the caudal, dorsal, anal and ventral fin formation after hatching. About 20 days after hatching, the morphology of the fry was similar to the adult fish. These findings provide a basis for determining the complete ontogeny of P.parva, as well as facilitate the management and utilization of this fish.