Acetaminophen (ACT) and ibuprofen (IBU) are most frequently detected pharmaceuticals in aquatic ecosystem, and they can induce various harmful effects on aquatic biota. However, the toxicity of ACT and IBU on marine biota and their underlying toxic me...
Acetaminophen (ACT) and ibuprofen (IBU) are most frequently detected pharmaceuticals in aquatic ecosystem, and they can induce various harmful effects on aquatic biota. However, the toxicity of ACT and IBU on marine biota and their underlying toxic mechanisms are not well-understood. Thus, in this study, we investigated acute toxicity of ACT and IBU on the brackish water flea Diaphanosoma celebensis, and subsequently, transcriptional modulation of genes related to detoxification, antioxidant system, and ecdysteroid signaling pathway was analyzed. Acute toxicity test showed ACT and IBU have relatively less acute toxicity on D. celebensis (48-h LC50ACT: 120.72 mg/L and 48-h LC50IBU: 212.23 mg/L). After exposure to ACT, the expression of most detoxification-related genes was down-regulated, but the expression of cytochrome P450 (CYP) 360A8, glutathione S-transferase (GST) theta, and ATP-binding cassette (ABC) transporter B1 was significantly up-regulated following IBU exposure, which suggests that ACT and IBU might differently affect detoxification system of D. celebensis. However, the expression of most genes related to antioxidant system and ecdysteroid signaling pathway was significantly decreased following ACT and IBU exposure. These findings suggest that ACT and IBU may be metabolized by different mechanisms and have potential toxicity on redox homeostasis and reproductive process of marine zooplankton.