Distribution of aluminum in hair of Brazilian infants and correlation to aluminum-adjuvanted vaccine exposure.

BACKGROUND: Nursing children are exposed to dietary aluminum (in breast milk and/or infant formulas) and through aluminum-adjuvanted vaccines (AAVs). We studied total hair-Al concentrations of nursing children that had been immunized with hepatitis B, DTP, and meningococcal vaccines. METHODS: We studied the hair of 37 young children (aged 26 to 824 days) who were exposed to cumulative doses of Al ranging from 0.63 to 6.88 mg from AAVs. Graphite furnace atomic absorption spectrometry was used to reliably measure total Al concentrations in hair samples. RESULTS: The analytical method proved sensitive enough to quantify Al in the hair of nursing children. At current levels of exposure it is possible to determine total Al in hair sample of 1.65 mg. Cumulative doses of AAV in children ranged from 0.63 to 6.88 mg Al. Median hair-Al was 47.7 µg g⁻¹ (ranging from 12.2 to 221.9 µg g⁻¹). There was no statistically significant correlation between hair-Al concentration and age of child (r=-0.049; p=0.774), total exposure from vaccine (r=-0.078; p=0.643), or the time elapsed after the last AAVs (r=0.015; p=0.931). CONCLUSION: Aluminum in children's hair can be reliably measured but we are still uncertain how representative it can be of the Al body burden.