Simple method to determine the efficiency of a cream used for skin protection against solvents.

310-316. Most of the industrial organic solvents coming into contact with the skin are absorbed through it and enter the blood. They can then be detected in the breath, the analysis of which makes it easy to evaluate skin absorption. Such an evaluation can be made with and without the use of a skin protective (barrier) cream. A comparison of the results allows the efficiency of the cream to be tested. An example of the application of this method is described. The solvent was toluene and the cream tested was composed mainly of talc, glycerol, and water. Ten male volunteers exposed their hands to liquid toluene for 10 minutes. The elimination of the solvent was followed by breath analysis up to 3 hours after the exposure. Two or more sets of exposure were made under different conditions with and without the protective cream. The results show a good standard of efficiency when the cream is carefully and deeply applied. The efficiency of the cream was determined by testing the difference between the decay curves obtained with and without the barrier cream. A relative efficiency was estimated as a percent diminution of solvent excretion by taking the excretion after exposure of unprotected skin as 100%. It is shown that skin absorption for toluene compared with lung absorption may be important and has to be estimated where total exposure is concerned. The method devised here appears to offer simplicity. It is presented as a laboratory test to show the intrinsic value of the cream but its applicability in the field is also considered.