23yo son was removing roofing material and was covered by pitch dust x 1 wk. arms are red with peeling skin, looks like a really bad sunburn. pharmacist friend gave him silvadine, and he used an aloe plant to sooth. Son came home to visit (lives in another state) and just showed me. just bought Technu solution, spray w/ lidocaine and aloe, I am a nurse and have worked for a plastic surgeon in past, have seen burns and know that you should get dead skin off but aren"t quite sure what else to do and what this exposure to pitch can do long term. any ideas?