Fate of avermectin B1a on citrus fruits. 1. Distribution and magnitude of the avermectin B sub 1a and sup 14 C residue on citrus fruits from a field study
- Merck, Sharp and Dohme Research Labs., Three Bridges, NJ (USA)
An 8{mu}g/mL solution of ({sup 14}C)avermectin B{sub 1a}, the approximate field application rate, was applied to oranges, lemons, and grapefruit; a 10-fold higher rate was also applied to oranges. Immediately postapplication, {sup 14}C residues were 20-38 ng/g for the fruit treated at the field rate. Most of the residue was recovered in the surface solvent rinse at less than 2 weeks postapplication; however, after this time more of the residue was recovered from the rind fraction. The total recoveries of applied radioactivity were 61-90% and 33-50% at 1 and 12 weeks postapplication, respectively. The level of unextractable rind {sup 14}C residue from oranges treated at the 10{times} rate and harvested at 12 weeks (a worse case) was 4.9% of the applied dose (<2 ppb at the field rate). The inner pulp samples for all treatments had {sup 14}C residue levels below the detection limit of 0.4-0.8 ppb. The initial depletion half-life of avermectin B{sub 1a} was <1 week, with losses occurring within 30-40 min. For the 1-12-week postapplication period, the avermectin B{sub 1a} and {sup 14}C residue depletion half-lives were 20-38 and 56-98 days, respectively. Differences in the rate of dissipation of avermectin B{sub 1a} due to fruit type and application rate were observed.
- OSTI ID:
- 7190341
- Journal Information:
- Journal of Agricultural and Food Chemistry; (USA), Journal Name: Journal of Agricultural and Food Chemistry; (USA) Vol. 37:1; ISSN 0021-8561; ISSN JAFCA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Fate of the 8,9-Z isomer of avermectin B sub 1a rats
Fate of avermectin B sub 1a in lactating goats
Related Subjects
60 APPLIED LIFE SCIENCES
AGRICULTURE
CARBON 14 COMPOUNDS
CITRUS
DISTRIBUTION
FIELD TESTS
INDUSTRY
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAGNOLIOPHYTA
MAGNOLIOPSIDA
PESTICIDES
PLANTS
TESTING
TISSUE DISTRIBUTION
TRACER TECHNIQUES