Is abietic acid the allergenic component of colophony?

Abstract

In order to investigate whether abietic acid itself is the allergenic component of colophony, 2 commercial samples were extensively purified and tested in guinea pigs and in colophony-sensitive patients. In the modified FCAT method, sensitization was obtained with Portuguese colophony and when challenged with purified abietic acid, the animals showed no reaction. In the GMPT method, the animals were exposed to purified abietic acid. Challenging with 2 different samples of it gave no significant reaction. When patch tested, patients sensitive to colophony showed no reactions to abietic acid which had been purified immediately before the test. It is concluded that abietic acid itself is not a contact allergen.

Abietic acid [MAK Value Documentation, 2013]

“…In extensive experimental animal investigations with the FCA test and the maximization test, it was possible to show that purified abietic acid (99.8%; Karlberg et al 1985), as well as dehydroabietic acid (Hausen et al 1989), have if at all avery weak sensitizing effect. Unpurified commercially available abietic acid, tetrahydroabietic acid, podocarpic acid, levopimaric acid (Hausen et al 1989) and 13,14-dihydroxyabietic acid (synthetic product; , are classified as weak sensitizers.…”

“…Chemically pure abietic acid and dehydroabietic acid are at best very weak allergens, though they may be considered to be prohaptens (Hausen et al 1989;Karl-berg 1989Karl-berg , 1991Karlberg and Gäfvert 1996;Karlberg et al 1985Karlberg et al , 1994. Under the influence of light, heat and oxygen they form oxidation products such as hydroperoxides, peroxides, epoxides and ketones, which apparently occur or are formed regularly in preparations containing abietic acid-or dehydroabietic acidic.…”

“…1985) Purity/impurities commercially available abietic acid has a purity of 85% to 90% (no other details; Karlberg 1989) or 74% with 13.6% isopimaric acid and 7.5% dehydroabietic acid (Karlberg et al 1985); abietic acid and dehydroabietic acid [1740-19-8] can contain oxidation products, e.g. 13,14--epoxides, 13,14--epoxides, 7-oxo-or 15-hydroperoxy compounds (see Figure 2; Karlberg and Gäfvert 1996;Karlberg et al 1988 a, b) Production abietic acid is acomponent of raw tall oil (mixture of resin acids, terpenes and fatty acids) and one of the main components of rosin (colophony).…”

Abietinsäure [MAK Value Documentation in German language, 2002]

“…Chemisch reine Abietinsäure und Dehydroabietinsäure sind allenfalls sehr schwache Allergene, können aber als Prohaptene angesehen werden (Hausen et al 1989;Karlberg 1989Karlberg , 1991Karlberg und Gäfvert 1996;Karlberg et al 1985Karlberg et al , 1994 Gäfvert et al 1992;Hausen et al 1989Hausen et al , 1993Karlberg 1988Karlberg , 1991Karlberg und Gäfvert 1996;Karlberg et al 1988 c;Khan und Saeed 1994) wie 15-Hydroperoxyabietinsäure (Karlberg und Gäfvert 1996;Karlberg et al 1988 a, b), 13,14-C-Epoxyabietinsäure ), 7-Oxodehydroabietinsäure (Sadhra et al 1996(Sadhra et al , 1997, 15-Hydroperoxydehydroabietinsäure (Shao et al 1995) und Dehydroabietinsäureperoxid (Gäfvert et al 1992). Eine allergene Wirkung für Harzsäuren vom Pimarsäuretyp (Abb.…”

“…In eingehenden tierexperimentellen Untersuchungen mit dem FCA-Test und dem Maximierungstest konnte gezeigt werden, dass gereinigte Abietinsäure (99,8%;Karlberg et al 1985) ebenso wie Dehydroabietinsäure (Hausen et al 1989) kaum sensibilisierend wirkt. Ungereinigte handelsübliche Abietinsäure, Tetrahydroabietinsäure, Podocarpinsäure, Levopimarsäure (Hausen et al 1989) und 13,14-Dihydroxyabietinsäure (Syntheseprodukt;), wurden als schwache Sensibilisatoren eingestuft.…”