title: Quantitative 3D shape description of dust particles from treated seeds by means of X-ray micro-CT.
abstract: Crop seeds are often treated with pesticides before planting. Pesticide-laden dust particles can be abraded from the seed coating during planting and expelled into the environment, damaging nontarget organisms. Drift of these dust particles depends on their size, shape and density. In this work, we used X-ray micro-CT to examine the size, shape (sphericity) and porosity of dust particles from treated seeds of various crops. The dust properties quantified in this work were very variable in different crops. This variability may be a result of seed morphology, seed batch, treatment composition, treatment technology, seed cleaning or an interaction of these factors. The intraparticle porosity of seed treatment dust particles varied from 0.02 to 0.51 according to the crop and generally increased with particle size. Calculated settling velocities demonstrated that accounting for particle shape and porosity is important in drift studies. For example, the settling velocity of dust particles with an equivalent diameter of 200 μm may vary between 0.1 and 1.2 m s(-1), depending on their shape and density. Our analysis shows that in a wind velocity of 5 m s(-1), such particles ejected at 1 m height may travel between 4 and 50 m from the source before settling. Although micro-CT is a valuable tool to characterize dust particles, the current image processing methodology limits the number of particles that can be analyzed.
authors.affiliation: †BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, 3001 Leuven, Belgium.
authors.forename: Wouter
authors.initials: W
authors.lastname: Devarrewaere
authors.affiliation: ‡Agricultural Engineering, Technology and Food Science Unit, Institute for Agricultural and Fisheries Research (ILVO), 9820 Merelbeke, Belgium.
authors.forename: Dieter
authors.initials: D
authors.lastname: Foqué
authors.affiliation: §Institute for Plant Protection in Field Crops and Grassland, JKI, 38104 Braunschweig, Germany.
authors.forename: Udo
authors.initials: U
authors.lastname: Heimbach
authors.affiliation: †BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, 3001 Leuven, Belgium.
authors.forename: Dennis
authors.initials: D
authors.lastname: Cantre
authors.affiliation: †BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, 3001 Leuven, Belgium.
authors.forename: Bart
authors.initials: B
authors.lastname: Nicolai
authors.affiliation: ‡Agricultural Engineering, Technology and Food Science Unit, Institute for Agricultural and Fisheries Research (ILVO), 9820 Merelbeke, Belgium.
authors.forename: David
authors.initials: D
authors.lastname: Nuyttens
authors.affiliation: †BIOSYST-MeBioS, KU Leuven, Willem de Croylaan 42, 3001 Leuven, Belgium.
authors.forename: Pieter
authors.initials: P
authors.lastname: Verboven
mesh_terms: D004391:Dust / Q000032:analysis*; D021621:Imaging, Three-Dimensional; D010316:Particle Size; D016062:Porosity; D012639:Seeds / Q000737:chemistry*; D055114:X-Ray Microtomography; D003313:Zea mays / Q000737:chemistry*
chemical_list: D004391:Dust