CORRELATION OF ACTUAL STRAWBERRY HARVESTER EXPOSURE WITH THAT PREDICTED FROM ABAMECTIN DISLODGEABLE FOLIAR RESIDUES

Sixteen male strawberry harvesters were monitored during two 3-h harve sting periods for dermal exposure to abamectin, a miticide/insecticide . Upper body exposures were monitored by cotton undershirt dosimetry, hand rinses, and facial washes. Exposure was greatest to the hands (83 3 ng/h) followed by the torso (380 ng/h) with negligible residues dete cted on the face. With <1% dermal penetration, the average systemic ex posure was calculated to be 1.36 ng/kg/day. The ratio of the no-observ ed-effect level (NOEL) of 50 mu g/kg/day to the worker exposure of 1.3 6 ng/kg/day yielded a margin of exposure (MOE) of 36 800. Abamectin fo liar residues ranged from 40.7 to 0.17 ng/cm(2) at 2 h and 7 days afte r the second application, respectively. Dislodgeable foliar residue (D FR) data at the harvest time of 3 days after the second application, 0 .84 ng/cm(2), combined with the Zweig transfer factor (5000 cm(2)/h) a nd a dermal penetration of 1% resulted in a predicted worker exposure of only 5.6 ng/kg/day and a corresponding MOE of 8930. These results s uggest that DFR data may be used to conservatively predict worker expo sure to abamectin.