Ecotoxicological Effects of Chlorhexidine and Butyl Paraben in Zebrafish (Danio rerio): An In Vivo Study

Aquatic ecosystems are essential for maintaining global biodiversity, providing freshwater, supporting key biogeochemical cycles, and sustaining a wide range of flora and fauna.However, these ecosystems are increasingly threatened by the continuous discharge of untreated or inadequately treated wastewater.This wastewater often contains a complex mixture of chemicals, materials, and products.Many of these substances are biologically active and environmentally persistent, allowing them to accumulate in aquatic organisms.Even at trace concentrations, such contaminants can disrupt physiological functions in aquatic biota, alter community dynamics, and compromise overall ecosystem integrity.This growing concern underscores the need for comprehensive ecotoxicological assessments to better understand and mitigate the risks associated with emerging pollutants. 1 While traditional pollutants such as heavy metals and chemical pesticides have been extensively investigated, recent years have witnessed an increasing shift in focus toward emerging environmental contaminants (ECs), a broad group of synthetic and naturally occurring compounds that are frequently detected in aquatic environments but remain largely unregulated and