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Abstract The results showed that decreases in the free-space concentration of EDN in the fumigation chambers containing tested commodities followed first order kinetics with higher correlation coefficient (R2), except for wheat flour due to a higher DROP in the first hour of fumigation of more than 93.5% of the initial dose applied. These findings were in agreement with previous reports on fumigant sorption into commodities. Pranamornkith et al. (2014) showed that sorption of EDN by timber followed a two-phase exponential function, and EDN sorption by pine logs was previously found to fit an exponential decay function (Najar-Rodriguez et al., 2015). In addition, the sorption of other fumigants into commodities, including methyl bromide, phosphine, ethyl formate and sulfuryl fluoride (SF), was found to follow the first order kinetics equation (Hilton and Banks, 1997; Daglish and Pavic, 2008; Weller, 2003; Hwaidi et al., 2015). The present study showed that EDN sorption varied among the tested commodities. This variation in sorption between commodities may be related to commodity constituents, moisture content, the interaction between the fumigant applied and the commodity, different surface area, physical and chemical properties of commodities (Banks, 1986). The sorption rate of EDN into wheat flour was much greater than other commodities, which was comparable with Hwaidi et al. (2015) who indicated that the sorption rate of SF was much higher in wheat flour and semolina than whole wheat. Also, Sriranjini and Rajendran (2008) reported that wheat flourwas a more sorptive commodity to SF than either whole wheat or corn with sorption percentages of 60.8, 17.7 and 13.3%, respectively. In general, fumigant sorption into commodities containing high fat content is much greater than that of low fat or high starch contents (Berck, 1964; Punj, 1969). In contrast, our results indicated that sorption of EDN by corn and pinto beans was lower than that of wheat kernels or wheat flour. However, tobacco leaves had the lowest sorption rate (0.071) compared to other commodities at both application rates, which may be related to the amount of fat and starch in tobacco leaves compared to other commodities that contain higher fat or starch content. In addition, the present report revealed that EDN was highly sorptive into all commodities tested compared to other fumigants, which was consistent with previous works. For example, Ren et al. (2011) found that the sorption rates. |