Comprehensive metabolome and growth effects of thiamethoxam uptake and accumulation from soil on pak choi

Extensive use of the neonicotinoid thiamethoxam (TMX) results in its deposition in soil, which can then be absorbed and translocated in vegetables. Here we analyzed the comprehensive effects of TMX on pak choi. The TMX translocation factor (TF) was 0.37-11.65 and 0.46-39.75 for low and high treatments over 28 d, respectively, indicating its ready ability to move from the roots to the leaves of these plants. This uptake was associated with significant decrease in the fresh weight, and increase in vitamin C (VC), soluble sugars and soluble solid of pak choi. A metabolomic analysis revealed that fatty acids and purine nucleosides significantly decreased, and flavonoids and carbohydrates increased in the presence of TMX. TMX exposure thus influenced plant growth and disrupted the carbohydrate and lipid metabolism pathways. Our study raises concerns for food safety risk associated with TMX-contaminated soil.