Genotoxic and morphological damage in Hippocampus reidi exposed to crude oil

The present article investigates the responses of Hippocampus reidi exposed to crude oil (10 mL/L) for time periods that are characteristic of acute (12, 24, 48 and 96 h) and subchronic (168 and 336 h) and its recovery at 168 h, such as to assess H. reidi as a good sentinel species. These responses were examined by genotoxic and morphologic analyses. There was a control group (n=8) for each group exposed to crude oil (n=8). The results revealed the occurrence of genotoxic damage in erythrocytes of all specimens exposed to crude oil. The damage index (DI) observed for all exposure times were significantly higher compared to those of the respective control groups; the highest DI was observed in specimens exposed to crude oil for 168 h. The group exposed to crude oil for 96 h had the highest values of micronuclei than all other exposure times. Microscopic inspection of the H. reidi gills revealed the presence of several histopathological changes, all of which were minor severity (structural normal gills). The recovery experiment revealed a significant reduction in genotoxic damages, however the period of 168 h was not sufficient to recuperate the histopathology damages. The Seahorse has presented significant genotoxic responses after exposure to crude oil. Furthermore, it is a sedentary fish and is widely distributed; in conclusion this specie can be considered an excellent sentinel organism.

► Crude oil can provoke genotoxic and morphologic damages in Sea horse.
► Acute and subchronic exposure and recovery.
► Morphologic alterations were consistent to crude oil exposition.
► Comet assay was better biomarker than micronucleus to Sea Horse exposed to crude oil.
► The Seahorse can be considered an excellent sentinel organism.