Penetration of aluminum chlorohydrate following dermal application is minimal, with the rate being around 0.01% and up to 0.06% in pre-damaged skin. In a preliminary study, dermally applied aluminium chlorohydrate displayed 0.012% of the applied aluminium being absorbed through the skin, which accounts for 4 mcg of aluminum following a single dermal application. This is about 2.5% of the aluminium typically absorbed by the gut from food over the same time period.