Spray drift, environmental behavior

It is important for the public to recognize that there is no fixed distance or buffer zone for a safe distance to provide protection from spray drift. This will be a function of the pesticide being used, its toxicity and environmental behavior such as bioaccumulation, the nature and sensitivity of the downwind sites, and the nature of the application method, meteorological conditions, and so on. 

The interpretation of the effects of such drift, particularly its potential for adverse effects on human health, is dependent on some of the parameters of environmental behavior shown on Table VIII. The dose is given at 2 lbs/acre and translated into a deposit level of 20 mg/square foot, which is more useful in the interpretation of exposure data. The figures given for the deposit amount from spray drift at 100 yards and 1/2 mile are the figures for drift from a coarse spray on flat land for small target areas and are average drift amounts. The figure of 20 mg/kg is the NOEL for 2,4-D. 

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