Impact of Daily Antiperspirant Use on the Systemic Aluminum Exposure: An Experimental Intervention Study

Background and Objectives: Adverse health effects such as neurotoxic and carcinogenic effects through aluminum from cosmetic products have been repeatedly discussed. The dermal uptake and impact on the systemic aluminum load is still poorly understood. Therefore, we investigated the effect of daily antiperspirant use on the systemic aluminum load under real-life conditions. Methods: 21 healthy subjects meeting certain selection criteria to ensure a low systemic aluminum background load were asked to use a commercial aluminum-containing antiperspirant for 14 days. A questionnaire enquired about shaving habits and other sources of aluminum. Aluminum levels were measured before and after the exposure in 24-h urine and plasma using atomic absorption spectroscopy. Urine samples (n = 6) with <700 mg/day creatinine excretion or more than 30% difference in 24-h creatinine excretion were excluded from further analysis. Results: No significant increase in plasma aluminum concentration or total excreted aluminum per day before and after exposure was measurable. No sample exceeded the reference values of the general population (maximum: 9.42 µg/g creatinine and 2.1 µg/L plasma). Shaving habits did not have a significant influence on the systemic aluminum load. Also, no correlation between the total amount of antiperspirant applied and the systemic aluminum level could be demonstrated. Conclusions: No measurable contribution to the overall systemically available aluminum load due to daily use of an antiperspirant for 14 days could be shown, but real-life data concerning long-term use or higher concentrations are still lacking. Considering toxicological occupational exposure data, adverse neurotoxic changes are unlikely in the case of urinary excretion of <50 µg aluminum/g creatinine (= no observed adverse effect level), even following long-term exposure.