[Cocobolo wood, a forgotten eczematogen? Recent findings on the skin allergen of cocobolo wood (Dalbergia sp.)].

Delayed hypersensitivity due to occupational contact with Cocobolo wood and playing the recorders manufactured from this species was proven in three of five patients by positive results in patch tests with its constituents R-4-methoxydalbergione and obtusaquinone. The biogenetic correlations of these isomeric compounds, the strong epicutaneous reactions in the patients as well as the strong sensitizing capacity of obtusaquinone obtained in guinea pig sensitization experiments corroborate the supposition not to consider the dalbergione but the quinone methide (obtusaquinone) as the inductor of Cocobolo hypersensitivity. As both constituents possess inhibitory activity toward marine micro-organisms, such as the marine borer Teredo navalis, they are intended to be used in ship paintings and protection coatings. Thus, Cocobolo will no longer remain a forgotten sensitizer but will become--in case of realization--a risk for certain painters in the future.