Serial fumigation of processed and packaged food with air washed residual methyl bromide from fumigation chambers.

The poosibility of usiug residual methyl bromide left
after exposure in fumatoria for more fumigations in sub·
sequent fumatoria was demonstrated. Use of the air washing
technique to obtain more fumigant concentralion in the
atmosphere of the next fumatorium in the series proved
advantageous. In the 24 hours exposure series, the residual
concentralions in air were low because of prolonged sorption
by the commodities, so nol more than two fumigations
could be attempted, whereas in the varied-exposure series 3
fumigations could be attempted with the initial dose of 32
mg/L, stretching over an integrated exposure period of 27
hr with 100% mortality of the test insects.