Composition of <i>Myroxylon pereirae</i> Resin and Colophonium for Patch Testing

The major ingredients of the volatile fractions of M. pereirae resin and colophonium are quite different; common haptens in volatile ingredients cannot readily explain co-reactivity. M. pereirae resin has cinnamic acid- and benzoic acid derivatives in common with propolis and in addition (E)-nerolidol and vanillin with Brazilian propolis and benzyl alcohol with Chinese propolis. Colophonium shares various ingredients with Brazilian propolis but few with the Chinese variety.