Re-entry intervals

Figure 1 was taken from an unpublished report, DuPont Study No. AMR 4392-97, Dissipation of Dislodgeable Foliar and Soil Residues of Oxamyl Following Application of Vydate L Insecticide to Tomatoes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. 

To calculate the safe re-entry interval (REI), the margin of exposure (MOE) must be considered. Worker risk is measured as a margin of exposure and is related to how closely the occupational exposure comes to the no observed adverse effect level (NOAEL, for oxamyl 50 mg kg day ). MOE is defined as... 

Arizona cauliflower scouting represented low crop activities. Five orange harvesters and five lemon tree pruners were tested using concurrent dosimetry and urinary monitoring techniques. The re-entry intervals were 43, 2, and 1 days for the orange harvesters, lemon tree pruners, and scouts, respectively. Re-entry workers were monitored for 5- to 6-hr work days in California and for a 4-hr work day in Florida and Arizona. 

Serat, W.F., D.C. Mengle, H.P. Anderson, E. Kahn and J.B. Bailey, (1975). On the estimation of worker re-entry intervals into pesticide treated fields with and without exposure of human subjects, Bull. Environ. Contam. Toxicol, 13, 506-512. 

Spear, R.C. (1980). Technical problems in determining safe re-entry intervals, J. Environ. Pathol Toxicol, 4, 293-304. 

Research Needs 369 EXPOSURE MITIGATION 369 Protection Factors 369 Labeling 370 Re-entry Intervals 371... 

Re-entry intervals (also known as restricted entry intervals) provide a mechanism to reduce post-application exposnre potential by preventing entry to treated areas until an established interval of time (e.g. 24 h) has expired. 

Although climate-specific and cnltivation-specific considerations may merit different re-entry intervals, approaches for deriving re-entry intervals should be harmonized as much as possible. 

Restricted entry intervals (re-entry intervals) The time after apphcation of a pesticide during which workers are not allowed to enter the treated area (Whit-... 

The re-entry interval is defined as the time between last application and the time a worker can enter a field and work for more than one-half hour without protective clothing. Re-entry is... 

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