Foliar residue leaves

Extracts of gloves, extracts of foliar dislodgeable residue and absolute foliar residues, and filters containing thiophanate-methyl were analyzed by reversed-phase HPLC and ultraviolet detection at 254 nm (Engel, 1988). The LOD was 50 mg/L for extracts of filters and gloves, and 10 mg/L for leaf samples. Recovery was > 90%, and the "between days" CV of the analytical chemical method was < 5%. 

Reduced growth >25% foliar damage leaf residues of 76-324 mg B/kg ash weight (1)... 

Dislodgeable foliar residues from strawberry plants were obtained by collecting 48 circular leaf punches on a random basis, starting with the first day post-application of carbaryl, finishing on the last day of the study (Day-17 post-application). A description of the mechanical leaf punch and the collection technique may be found elsewhere (jj. 

After the foliar samples have been collected they are placed on wet ice and brought back to a facility for dislodging. The goal of the dislodging procedure is to extract the residue present on the leaf surface that is available for transfer from the leaf. Residues that have been absorbed into the plant matrix would not be available for transfer. The best practice is to dislodge the residue within 4 h of collecting the sample. 

Dislodgeable foliar pesticide residues and leaf dust were isolated by methods described in the published literature (5.6.7.8). Basically the method for the extraction of dislodgeable carbaryl... 

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... 

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