Many terpenes may autoxidize under certain conditions to form terpene hydroperoxides, which have been reported to be skin sensitizers that may cause allergic contact dermatitis. The fragrance industry is currently required to monitor terpene hydroperoxide levels in many raw materials by iodometric titration (aka; the peroxide value, or POV test), and to reject lots that exceed a specification limit. We have found that compounds containing the 2‐oxoacid moiety (the “pyruvic acid” moiety) react readily with organic hydroperoxides via an oxidative decarboxylation mechanism. The reaction products include an alcohol corresponding to the reduced hydroperoxide, carbon dioxide, and a carboxylic acid that is one carbon shorter than the starting 2‐oxoacid. Because the hydroperoxide is irreversibly consumed by this reaction, the POV of a 2‐oxoacid‐treated sample is effectively lowered. It follows that the skin sensitizing potential of the treated sample should also be lowered as a result of the hydroperoxide removal.

中文翻译：

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氢过氧化物对2-含氧酸的氧化脱羧可用于降低柑桔油中的过氧化物值

许多萜烯在某些条件下可能会自氧化形成氢过氧化萜烯，据报道它们是可能引起过敏性接触性皮炎的皮肤致敏剂。目前，香料行业需要通过碘量滴定法（又称过氧化物值或POV测试）来监测许多原材料中萜烯氢过氧化物的水平，并拒绝超过规格限制的批次。我们发现，含有2-氧合酸部分（“丙酮酸”部分）的化合物可通过氧化脱羧机制与有机氢过氧化物反应。反应产物包括与还原的氢过氧化物相对应的醇，二氧化碳和比起始2-氧代酸短一碳的羧酸。由于该反应不可逆地消耗了氢过氧化物，有效降低了2-氧代酸处理样品的POV。由此可见，由于氢过氧化物的去除，处理过的样品的皮肤致敏电位也应降低。