Dermatitis from propolis.

22 patients with dermatitis from propolis were studied. In all the 21 tests with propolis were positive, and in 19 they were also positive to balsam of Peru. The chromatogram of the balsam and propolis show marked similarity and 3 identical peaks could be recognised in both substances. Among the patients sensitive to balsam of Peru and propolis, 12 were tested with some common components; 3 were positive to cinnamyl cinnamate, 2 to vanillin and 1 to benzyl cinnamate. Chromatograms of the 3 propolis samples from the Warsaw region were very similar, but not identical. Some of the patients were tested with 35 essential oils and eugenol. Sensitivity to clove oil was common.