Hazards and Health Risks of the Antibacterial Agent Triclosan to Fish: A Review

Triclosan (TCS) is a widely used antimicrobial agent found in personal care products and household cleaners. While valued since the 1960s for its ability to inhibit bacterial fatty acid synthesis, its environmental persistence, ecotoxicity, and bioaccumulative potential have raised significant global concern. The increased use of disinfectants during the COVID-19 pandemic has further exacerbated its prevalence as an aquatic pollutant. In the environment, TCS is distributed through water bodies and sediments, undergoing processes such as biodegradation and photochemical degradation. Its bioaccumulation poses a substantial threat to aquatic organisms, particularly fish. A growing body of research indicates that TCS acts as an endocrine disruptor and developmental toxicant, with documented adverse effects encompassing impaired embryonic and larval development, skeletal malformations, and induction of oxidative stress, mitochondrial dysfunction, DNA damage, and inflammatory responses. Furthermore, TCS exposure is linked to reproductive toxicity, including altered sex hormone levels and diminished reproductive capacity. This review consolidates current knowledge on the chemical properties, environmental fate, biodegradation pathways, and ecotoxicological impacts of TCS, with a specific emphasis on its multifaceted health risks to fish. The synthesis aims to provide a foundation for future research, inform environmental risk assessments, and support the development of evidence-based regulatory measures.