A preliminary study of the dermal absorption of aluminium from antiperspirants using aluminium-26

Aluminium chlorohydrate (ACH), the active ingredient in many antiperspirants, was labeled with the radioisotope Al-26. The labeled ACH was then fractionated into about 100 samples using gel filtration chromatography. Each fraction was analyzed for Al-26 and total aluminium content. Aluminium-26 was only detected in the fractions that also contained aluminium, which verified that the ACH was uniformly labeled. 84 mg of the labeled ACH was then applied to a single underarm of two adult subjects with blood and urine samples being collected over 7 weeks. Tape-stripping and mild washings of the skin were also collected for the first 6 days. Results indicate that only 0.012% of the applied aluminium was absorbed through the skin. At this rate, about 4 mug of aluminium is absorbed from a single use of ACH on both underarms. This is about 2.5% of the aluminium typically absorbed by the gut from food over the same time period. Therefore, a one-time use of ACH applied to the skin is not a significant contribution to the body burden of aluminium. (C) 2001 Elsevier Science Ltd. All rights reserved.