Keywords: 
• fungicide /
• endocrine disrupting chemicals /
• adverse outcome pathways (AOP) /
• ecological risk assessment

Abstract: Triadimefon is a broad-spectrum, systemic fungicide, belonging to the triazole family. With adjustment of the national policy and agricultural planting structure, usage of triadimefon in China has been increasing annually. In present review, the environmental behavior, ecotoxicity and ecological risk of triadimefon are discussed in Chinese surface waters. With the solubility of triadimefon, residues desorbed from soil can be transported by rain to surface or groundwater. Concentrations of triadimefon in surface water in China as great as 12 μg·L^-1, and with higher detected rate and concentration in wet season. Triadimefon with half life of 15~43.3 days in environment, it would accumulate persistently in the water environment and cause adverse effect to aquatic organisms due to its consistency and adsorption. Long-term exposure of aquatic organisms to triadimefon has potential to disrupt development or reproduction and can cause malformations that adversely affect fitness and survival of juveniles although the mechanisms are unclear. The most important adverse outcome pathways (AOP) was that disrupting hormone level by inhibiting enzyme activity of cytochrome P450, and then impacting organisms reproduction, growth and development which reducing population density lastly. Potential deleterious effects and hazards or risks of exposure of aquatic organisms from current patterns of use of triadimefon in surface water if of concern, especially for waters near rice field in wet season.