Metabolomics Reveals Antioxidant Stress Responses of Wheat (Triticum aestivum L.) Exposed to Chlorinated Organophosphate Esters

decreased, while the levels of carotenoid and activities of antioxidases, malonaldehyde, and reactive oxygen species increased significantly in both the root and shoot, indicating that the target OPEs caused significant oxidative stresses and affected photosynthesis in wheat. Untargeted metabolomics revealed concentration- and species-dependent metabolic responses of the three OPEs. Saccharides were downregulated, which might be due to the reduced photosynthesis activities. On the other hand, the chlorinated OPEs induced increases in respiration and antioxidative metabolites, revealing that the antioxidant system of wheat was active in scavenging ROS. The disturbance of tris(1,3-dichloro-2-propyl)phosphate on the metabolisms in wheat tissues was the strongest. These results contribute to the food safety and crop quality assessment of chlorinated OPEs and clarify the underlying mechanisms of their phytotoxicities.