Photometric determination of human serum bromide levels--a convenient biomonitoring parameter for methyl bromide exposure.

Methyl bromide is one of the most important pesticides for the control of insects, fungi and nematodes. Serum bromide has been proposed as a biomonitor for occupational exposure to methyl bromide. Therefore, a novel, sensitive photometric method was developed for the determination of serum bromide at concentrations relevant for such exposure. Further possible applications are monitoring of intoxication victims and halothane narcosis. Using the method we have established a mean serum bromide level of 4.13 +/- S.D. 1.05 mg/l (n/64) in a group of healthy female and male volunteers not knowingly exposed to bromide or bromine containing organics. Serum of a subject accidently exposed to methyl bromide revealed a bromide level of 11.5 mg/l serum, while two individuals exposed to methyl iodide had no elevated levels. A group of 30 agricultural workers showed a mean serum bromide level of 15.33 +/- S.D. 1.90 mg/l at the end of the methyl bromide application season.