Ethylene dibromide fumigation of California-grown citrus: effect of dosage, temperature, and load factor on gas concentration, sorption, and residues

Ethylene dibromide (EDB) fumigation of commercially packed lemons, naval oranges, and "Valencia" oranges showed that lemons and navel oranges were equally sorptive of EDB; "Valencia" oranges were less sorptive. Increased dosages produced higher gas concentrations during the exposure time (CT products), but had no significant effect on sorption. Rates of desorption of EDB from most to least rapid from fumigated citrus stored at 5 degree C were lemons greater than navel oranges greater than "Valencia" oranges. Levels of residual EDB in fumigated citrus fruits stored at 5 degree C would reach less than or equal to 0.25 ppm (250 ppb) in 21 plus or minus 2.8 days for lemons, 31 plus or minus 3.5 days for navel oranges, and 41 plus or minus 5.7 days for "Valencia" oranges.