Any soluble substance can penetrate the epidermis and enter the blood stream if the exposure is prolonged. However, if you are talking about PCP in the powder form, chances are that you won't absorb enough of it from skin contact to have an impact on you (unless you apply it to an adhesive and tape it to your body). There is more risk with the liquid form, but it would require a certain period of contact, as well. If you just touched it with your finger, you'll probably be just fine.