Characteristics of applicator exposure to synthetic pyrethroid in ULV-handheld and ULV-ULA spray applications

The technique of ultra-low volume by ultra-light aircraft for pesticide spray application has been discussed for some time in North America, mainly due to the air worthiness of such an aircraft which was not designed to carry appreciable amounts of payload. The risk factor of such application in insect control has not been determined, while applicator exposure to insecticide in ULV application by manual sprayer was assessed. An attempt was made to produce, by a series of field exposure measurements, a set of applicator exposure data for ULV-ULA and to compare the results with the data produced in synthetic pyrethroid application by using a hand-held ULV applicator. The applicator exposure of hand-held operation resulted in as high as 1000 times the exposure of aerial applicators indicating the effect of work practices and man-machine relationships. A delineation of toxic dose for these two types of applications shows that the aerial application could provide some benefits in reducing applicator exposure potential.