Ethylene Dibromide Residues in Fruit Fumigated for Quarantine Treatment Against the Caribbean Fruit Fly, 1979-80

Various fruits were fumigated with ethylene dibromide (EDB) in a 50 ft3 chamber for 2 hours, aerated 1 hour via an exhaust blower, and stored. A temperature of about 75°F was maintained during all stages via air conditioning. EDB was applied either at a dose level of 8 ov/1000 ft3, which is the level currently used commercially as a quarantine treatment for grapefruit being shipped from Florida to Japan, or at 16 ov/1000 ft3 in the case of fruits for which no effective dosage has been established. Samples of fruit were taken at various intervals after fumigation and assayed for residues of EDB by using steam distillation for separation and purification and gas chromatography with an electron capture detector to quantitate. Inorganic bromides were not determined. The data (see table) indicate that the amount of EDB absorbed and retained is highly dependent on both the type of fruit fumigated and the amount of fumigant applied.