# Thalassophryne maculosa (Batrachoididae: Thalassophryninae) as a Bioindicator of Mercury-Induced Genotoxicity

## TL;DR

This study shows that Thalassophryne maculosa is a sensitive marine fish that can detect mercury-induced genetic damage in coastal ecosystems.

## Contribution

The study introduces T. maculosa as a novel bioindicator for mercury-induced genotoxicity in aquatic environments.

## Key findings

- Mercury exposure caused dose- and time-dependent nuclear abnormalities in T. maculosa.
- Significant chromosomal damage was observed at mercury concentrations below regulatory thresholds.
- T. maculosa shows high sensitivity to mercury, making it suitable for environmental monitoring.

## Abstract

Environmental monitoring requires reliable bioindicators to assess the genotoxic effects of pollutants in aquatic ecosystems. In this study, the marine fish Thalassophryne maculosa was evaluated as a bioindicator of genotoxicity through the application of the micronucleus test. Fish were exposed to varying concentrations of mercuric chloride (HgCl2) (0.1, 0.25, and 0.5 µg HgCl2/g body weight) over different time intervals (24, 48, 72, and 96 h). A dose- and time-dependent increase in nuclear abnormalities, including micronuclei, was observed, with significant chromosomal damage detected at 0.25 and 0.5 µg HgCl2/g body weight. These results demonstrate the sensitivity of T. maculosa to mercury exposure, even at concentrations below regulatory safety thresholds, emphasizing its suitability as a bioindicator for detecting genotoxic contamination in coastal ecosystems. This study provides critical insights into the ecological risks posed by mercury and highlights the potential of T. maculosa to enhance environmental monitoring programs, particularly in regions vulnerable to heavy metal pollution.