Piperonyl Butoxide

How Much PBO is Absorbed Across the Skin?

The available data indicate that less that 3% of the amount on the skin (forearm) is absorbed over an 8-hour period (Selim, 1995).  Other studies with a pediculicide formulation indicate that about 2% crossed the skin and about 8% crossed the scalp (Wester et al., 1994).