Behavioral effects of acute exposure of zebrafish (Danio rerio) to arsenic and ampicillin, and the protective role of quercetin

Water contamination with heavy metals and pharmaceutical residues is a major threat to aquatic ecosystems, affecting the health and behavior of non-target organisms. In this study, we investigated the potential protective role of quercetin (QUE), a natural antioxidant, against behavioral deficits induced in zebrafish (Danio rerio) by combined exposure to arsenic (As) and ampicillin (AMP). The experiment included four groups: a control group, a group exposed to QUE (1000 µg L?¹), a group exposed to As (50 µg L?¹) and AMP (100 mg L?¹), and a group administered with a combination of As, AMP, and QUE. The fish were subjected to acute exposure (96 hours) and, at the end of this period, social behavior parameters were evaluated. The results showed that concomitant exposure to As and AMP significantly affected social behavior parameters. In addition, co-administration of QUE partially ameliorated these behavioral changes, although complete normalization was not achieved. These findings highlight the behavioral toxicity of chemical mixtures in aquatic organisms and suggest that antioxidant supplementation may provide a partial neuroprotective strategy.