Proposal of limit concentrations for skin irritation within the context of a new EEC directive on the classification and labeling of preparations.

In this study, solvents belonging to different chemical families were tested for their irritating properties to the skin. The irritating potential of a chemical is expressed as its concentration in a nonirritant diluent beyond which irritation of the skin may be expected in the sense of EEC Directive 79/831/EEC. The substances were applied onto the shaved skin of rabbits by means of a modified Finn chamber for 4 hr. Afterward the exposure chamber was removed and the skin cleaned. Reading of erythema and edema was performed according to the scale of Draize at 1, 24, 48, and 72 hr after the removal of the patch. On the basis of the readings obtained the different dilutions of the organic solvents tested were classified as irritant or not according to the interpretation rules laid down in EEC Directive 83/467/EEC. On the basis of the structure-activity relationships found within each chemical family the irritation potential of the other members of the family could be derived via interpolation.

Some thoughts on a possible regulatory approach at EEC level on the classification and labeling of dangerous preparations.

At the present time no European directives on classification, packaging, and labeling exist which cover all dangerous preparations of chemicals. To develop such a directive, the Commission of the European Economic Community services, at the request of and in close collaboration with experts of the member states, has conceived a method for evaluating the toxicity of mixtures of chemicals. This method consists of (a) the characterization of each constituent by means of an index and (b) the classification of preparations for each route of administration on the basis of their toxicity. The index is a figure representing the degree of dilution needed to render the substance not dangerous in the sense of the EEC Directives on the classification of dangerous substances; the highest index among those obtained for acute and chronic toxicity is taken to characterize the substances. An indication of toxicity is obtained by applying the simple equation sigma (P X I), where P is the percentage and I is the index of each constituent. The most stringent classification among those obtained for the three routes of administration is taken for the final classification of the preparation on the basis of its acute and chronic toxicity. Other toxicological effects such as irritation, corrosion, sensitization, mutagenesis, teratogenesis, and carcinogenesis are not considered.