Toxic effects of benzene on aquatic organisms with different trophic levels in simulated accidental spills using indoor artificial streams

Benzene, a toxic hydrocarbon, poses a significant threat to aquatic ecosystems, but the impact of accidental spills on aquatic organisms remains underexplored. This study simulates short-term benzene exposure in an artificial stream, evaluating its effects on aquatic species from different trophic levels, including periphytic algae, invertebrates (<i>Moina macrocopa, Glyptotendipes tokunagai, Limnodrilus hoffmeisteri</i>), and fish (<i>Zacco platypus, Aphyocypris chinensis</i>). Benzene concentrations of 150, 330, and 726 mg/L were introduced for 4 h to assess the biological responses of these species and their potential as sentinel species. <i>Z. platypus</i> exhibited the highest sensitivity, with significant mortality during benzene exposure, suggesting its potential as an early sentinel species. During post-exposure period, <i>M. macrocopa</i> exhibited reduced survival and fecundity, though reproductive recovery was observed over time. <i>G. tokunagai</i> populations also declined at high benzene levels. In contrast, periphytic algae, <i>L. hoffmeisteri, A. chinensis</i>, and fish growth were largely unaffected. These findings highlight the varying susceptibility of aquatic species to benzene exposure and suggest that <i>Z. platypus, M. macrocopa</i>, and <i>G. tokunagai</i> may be valuable for monitoring both immediate and delayed toxic effects in aquatic environments following benzene spills.