Background levels of bromide in human blood.

A total of 183 random, whole-blood specimens was collected from healthy individuals within the State of Queensland (Australia), and the bromide concentration was determined by wavelength-dispersive X-ray fluorescence spectrometry (WDXRF). The intensity of the tube Compton scatter line was used to account for differences in matrices between the aqueous calibration standard and whole-blood specimens. Technical details of the WDXRF method are included in the experimental section of the paper. The overall mean for bromide in human blood was 5.3 +/- 1.4 mg/L and ranged from 2.5 to 11.7 mg/L. Associations between bromide levels and variables including age, gender, weight, height, and postcode address were examined by ANOVA and Pearson's correlation. Data indicate that aged persons (45-65+ years) are more likely to have higher bromide levels than younger persons (15-25 years). Our results also suggest differences in bromide levels between the sexes in similar age groups. Average levels were higher in females in most age groups. The reason for this difference requires further detailed investigation. No correlation was observed between bromide levels and height or weight of donors. No significant differences in bromide levels were found in persons living in the highly populated southeast region of Queensland compared with those living in the less urbanized northern parts of the state.