RELATION OF TEMPERATURE TO ETHYLENE DIBROMIDE DESORPTION FROM FUMIGATED WHEAT

The desorption of ethylene dibromide from fumigated wheat aerated at temperatures of 0-45 °C as determined by extraction with two different solvents and by steam distillation was found to increase as the temperature decreased. The maximum amount of extractable residue was obtained with an acetone-water mixture while petroleum ether extracted only the less-tightly bound portion. Desorption of this portion seemed to be inversely related to temperature and the effect was found to be reversible. Labeled ethylene dibromide was used to substantiate the results found by chemical analysis and to determine residue rates of desorption at different relative humidities. Considerably greater desorption was found to occur at high rather than at low humidities. © 1979, American Chemical Society. All rights reserved.