Application for the Reassessment of a Hazardous Substance under ...

5.18 The Task Specific Factors (TSF), suggested in the UK CRD model, are not thatappropriate for out-door activities as they were designed for the first tier of anexposure assessment relating to harvesting ornamentals and to the re-entry ofgreenhouses approximately 8-16 hours after treatment, but no better model isavailable. The indicative TSFs were 0.1 for cutting ornamentals; 0.01 for sorting& bundling ornamentals; 0.03 for re-entering greenhouses after low-volume-mistapplication; and, 0.15 for re-entering greenhouses after roof fogger application.As the tasks in these Scenarios are outside tending Berries/Fruit andVegetables/Cereals the lowest TSF 0.01 is proposed (assuming that inhalationexposure would be similar, or less, than that while bundling ornamentals indoors).5.19 Using the data from Casida et al. (1962), 20 minutes after application to the leafsurfaces of maize, cotton and peas about 50% was volatilised, while 5% remainson the leaf surfaces and 45% absorbed by the plant (in APVMA, 2008b). It isassumed therefore that only 50% of the application rate is available for possibleinhalation (See Appendix 5).Dichlorvos reassessment – application Page 312 of 436