Residual Levels of Three Fungicide (Difenoconazole, Flusilazole, Tebuconazole) Seed Coating Treatments in Corn and Chronic Dietary Risk Assessment for Different Populations

Abstract

To reduce the negative effects of excessive pesticide use, advancements have been made in the development and application of seed coating agents that require low application rates while maintaining prolonged efficacy. However, the distribution of systemic pesticides in seed coating agents across various parts of the crop can be uneven. Therefore, it is important to study the distribution and transport of systemic pesticides in seed coating agents during crop growth. This study used high-performance liquid chromatography coupled with triple quadrupole mass spectrometry to analyze the growth rate of corn treated with seed coating agents containing three commonly used triazole fungicides: difenoconazole, tebuconazole, and flusilazole. The differences in the absorption and transport of these triazole fungicides were examined, and a chronic dietary risk assessment was conducted. Results showed that all three triazole fungicides were absorbed into corn via roots and were subsequently transported to the stems and leaves; however, the absorption and transport rates of the different pesticides varied significantly. The concentrations of the fungicide residues were consistently the highest in the roots, with tebuconazole being transported upward and difenoconazole exhibiting minimal upward transport. Dietary risk assessment revealed that the chronic risk quotients for difenoconazole, flusilazole, and tebuconazole in corn were 76.625, 55.143, and 36.095%, respectively, indicating that these fungicides posed no significant risk to human health in China. This study provides an important reference for the scientific application of triazole fungicide seed coating agents in corn.