A NEW MASK FILTER CARTRIDGE USED TO DETERMINE APPLICATOR INHALATION EXPOSURE TO AN ALACHLOR HERBICIDE (LASSO(R)) DURING NORMAL SPRAYING OPERATIONS

A filter cartridge with a low air-flow resistance was designed for use on a modified half-face respirator worn during the application of ala chlor (Lasso(R)) herbicide. The filter trapped large concentrations of alachlor while retaining the ability to trap, small respirable drople ts. Moreover, alachlor could be recovered from the disassembled cartri dge and analyzed by conventional methods. The test cartridges were use d in combination with conventional personal air samlers to determine w hether the filters trapped more alachlor when compared with personal s amplers and to determine accurately, the amount of alachlor reaching t he breathing zone. Farmers sprayed alachtor in the form of alachlor (N = 7) or alachlor mixed with other herbicides or surfactant (N = 15). An average of 4 X 10(-2) mg or 2 X 10(-4) mg/kg of applied alachlor re ached the respirator filters. This concentration was 10-fold higher th an the alachlor recovered from the personal samplers. The new filter c artridge is better for determining the amount of alachlor reaching the breathing zone, and there is a low potential for significant inhalati on exposure to alachlor during normal spraying operations.