Modeling Environmental Fate, Transport, and Transformation of Pesticides: First-Order Kinetic Models for Regional and Global Applications

Abstract

Predicting pesticide residue masses in environments requires time- and cost-efficient fate models, particularly for high-throughput simulations of hundreds of active ingredients registered for use in agriculture. Due to the adaptability of first-order kinetics-based models for simulating the fate of pesticides in environments of varying scales, we conduct a review of these models in the present investigation. We discuss the application of first-order kinetics-based fate models in different types of compartments, such as environmental media, plant tissues, and animal bodies, and at different levels, such as the product-oriented life cycle impact assessment and the chemical-oriented health risk assessment. In addition, the first-order kinetics-based rate constants of pesticides provide process- and scenario-specific information on the fate, transport, and transformation of pesticides, which is essential for predicting pesticide residue masses in different environmental compartments. By varying the level of model complexity and site-specific rate constants of pesticides, the first-order kinetics-based fate models can be used as either comparable or absolute tools for conducting the life cycle impact assessment or the health risk assessment of pesticides, respectively. Bioconcentration, bioaccumulation, and biomagnification of pesticides may be evaluated with the aid of an inventory database of rate constants based on first-order kinetics in future research. We suggest incorporating non-first-order kinetic processes into the first-order kinetics-based model to advance risk assessment, as well as approximating non-first-order kinetic processes using first-order kinetics to facilitate life cycle impact or screening-level risk assessments.