Determination of bromide ion residues in broccoli after fumigation with methyl bromide by nonsuppressed ion-chromatography.

A nonsuppressed ion chromatography method using conductivity detection was performed to determine the concentration of bromide ions in broccoli following fumigation with methyl bromide (MB). After fumigation by MB with concentration up to 40 g/m3, bromide residue (BR) was considerably increased from the trace amount on unfumigated broccoli to about 12 ppm on fumigated broccoli. For probing the location of BR, broccoli was divided into stems and florets. The BRs were measured separately, and the results indicated that BRs only appear in the florets of broccoli.