Dislodgeable soil residue studies

Dislodgeable soil residue (DSR) studies are used to determine exposure of re-entry workers to soil surface residues. Soil surface residues are defined as test substance residue levels in <150-q.m soil particles (i.e. soil dust which can stick to a worker s skin, or can be inhaled). 

The USEPA, with input from the PMRA of Health Canada and the California Department of Pesticide Regulation (DPR), has substantially revised the USEPA Post-Application Exposme Monitoring Test Guidelines (USEPA, 1998a). This draft document has a broad scope and addresses passive dosimetry, biological monitoring, dislodgeable and transferable residue studies, soil residue studies and... 

Figure 1 was taken from an unpublished report, DuPont Study No. AMR 4392-97, Dissipation of Dislodgeable Foliar and Soil Residues of Oxamyl Following Application of Vydate L Insecticide to Tomatoes in the USA - Season 1997-1998 . This study has been submitted to the EPA and the data were used to establish and verify re-entry intervals. Data from this study will be used to provide an example of the topics discussed throughout this article. 

Reentry intervals are now established on the basis of (1) data on dermal absorption or dermal dose response (2) inhalation, dermal, and oral acute toxicity studies in animal models (3) foliar and soil residue dissipation data and, (4) available human exposure data. CDFA recommends several sources as useful guides for determining residues of pesticides on soil and leaf surfaces (dislodgeable residue) and conducting field reentry studies involving human volunteers (1-5). Human exposure studies may not be required if adequate animal data from (1) through (3) above are... 

DFR studies are designed and conducted to describe the decline profile of the active ingredient on foliage and/or soil surfaces when applications are made at the proposed label rate. These surfaces are limited to those which can be touched or disturbed by workers and from which residues can be dislodged, deposited on human skin and clothing, or inhaled during the performance of field work and harvesting operations. 

There are several suggested sources which are useful guidelines for determining residues of pesticides on soil and leaf surfaces (dislodgeable) and conducting field reentry studies involving human volunteers (3), (4), and (5.). Human... 

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