Emission of pesticides to the air during sprayer application: A bibliographic review

Abstract

Air pollution due to pesticides is a persistent problem in modern agriculture, and little is known on the reversibility of its effects on the environment and health. Pesticides contaminate the atmosphere through various pathways. This paper discusses techniques for measuring and modelling pesticide emission, and the factors that affect drift processes during spray application. Chemical analyses allow the concentration of polluting agents in the air to be measured, and different methods have been developed for measuring diverse pesticide groups. Several air-sampling methods, which give different results depending on the amount of air collected, are reported. The use of various tracers, such as fluorescent dyes, is widely reported. Brilliant sulphoflavine is the best fluorescent dye due to its low degradation in sunlight. Various collector devices are used, the most common being 2 mm diameter polymer lines. Although the report indicates a good level of collection efficiency, a complete understanding of the adhesion phenomenon is necessary. The use of mathematical and computational models to determine pesticide transport simplifies test and field evaluation. However, a detailed characterization of the agricultural environment, with temporal and spatial variations, is still necessary. The most common models are limited to transport and deposition of pesticides in the liquid phase to areas adjacent to treated fields. Drifting spray is a complex problem in which equipment design and application parameters, spray physical properties and formulation, and meteorological conditions interact and influence pesticide loss.