X-Message-Number: 12506 Date: Tue, 5 Oct 1999 19:28:06 -0700 (PDT) From: Doug Skrecky <> Subject: absorption of some Glycol Ethers Absorption of Some Glycol Ethers Through Human Skin in Vitro Environmental Health Perspective 57: 193-197 1984 The above reference has some absorption rates (mg/cm2/hr) through human (corpse) skin for a number of solutes as follows: (EG stands for ethylene glycol, PG stands for propylene glycol) Solute Rate of Absorption Synonym Methanol 8.4 Methyl alcohol 2-Methoxyethanol 2.82 EG monomethyl ether 1-Methoxypropan-2-ol 1.17 PG monomethyl ether 2-Ethoxyethyl acetate 0.800 EG monoethyl ether acetate 2-Ethoxyethanol 0.796 EG monoethyl ether Ethanol 0.57 Ethyl alcohol 2-(2-Methoxyethoxy) ethanol 0.206 DiEG monomethyl ether 2-Butoxyethanol 0.198 EG monobutyl ether 2-(2-Ethoxyethoxy) ethanol 0.125 DiEG monoethyl ether n-Butanol 0.06 Butyl alcohol 2-(2-Butoxyethoxy) ethanol 0.035 DiEG monobutyl ether In live animal testing the least toxic of these solutes appears to be: 1-Methoxypropan-2-ol, 2-(2-Methoxyethoxy) ethanol, and 2-(2-Ethoxyethoxy) ethanol. To give a rough idea how the above absorption rates would likely compare with common cryoprotectants, using glycerol as a base for red blood cell membranes is as follows: (from J General Physiology 62: 714-736 1973) Solute Relative absorption 2-Methoxyethanol 20.9 2-Ethoxyethanol 22.1 Ethanol 15.1 2-(2-Methoxyethoxy) ethanol 8.5 Ethylene glycol 5.8 Dimethyl sulphoxide 2.2 Glycerol 1.0 Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=12506