Carcinogenic compounds Safrole

This oil is produced from C. camphora Sieb. wood in China and Taiwan. Many chemotypes and also varieties from Cinnamomum species exist, but the true camphor oil is meant. This oil is rarely adulterated because of the cheap price but, fractioned and enriched in camphor up to 90%, is used to mix up camphor containing oils like rosemary, Spanish sage, and spike lavender. Smallest traces of safrole (a carcinogenic compound) shows the use of C. camphora higher boiling fractions. 

The observation that the urinary metabolite of safrole, 3-piperidyl-l-(3, 4 -methylenedioxyphenyl)-l-propanone is mutagenic and is structurally somewhat reminiscent of certain Piper amides, has led to the suggestion that some of these compounds should, perhaps be considered as potential mutagens or carcinogens [141]. Whether or not this proves to be a problem warranting major concern, it is well to note that mono-N-substituted amides can react with nitrite under acidic conditions, with formation of potentially carcinogenic N-nitroso products [131]. 

In fact, processed foods are better regulated in this area than are natural ones. Safrole, for example, is a compound found in oil of sassafras, isolated from the bark of the sassafras tree. Health food advocates often recommend sassafras tea as a restorative. At one time, manufacturers used safrole as a root-beer flavoring, but they stopped when safrole was found to cause cancer in test animals. Processed foods, you see, are not allowed to contain known carcinogens — but natural foods are. 

Safrole (25) and isosafrole were once important as the flavoring for root beer. These compounds are present in the plant extracts used to make this beverage. By the 1950s, however, most root beer was flavored with synthetically derived safrole. Both safrole and isosafrole were shown to be weakly carcinogenic and now have been banned for this purpose (Fishbein et al., 1967). These compounds have a methylenedioxy structure and are known to inhibit mixed-function oxidase enzymes. Two compounds of similar structure, piperonal (26) (naturally occurring) and piperonyl bu-toxide (27) (synthetic) are mixed function oxidase inhibitors and are used as synergists for insecticides such as pyrethrins, rotenoids, and Sevin (a carbamate insecticide) (Fishbein et al., 1967). 

To the consumer, the most evident properties of phenolic compounds are the colors and the astringent taste they impart to foods. With few exceptions such as safrole and coumarin, most low molecular weight plant phenols have been shown to be non-toxic/non-carcinogenic in experimental animals. Further, plant phenols form a very small portion of total food intakes under normal food consumption patterns and would not be likely to have any serious toxic or antiphysiological effects. It is therefore reasonable to ask, why consider food safety of plant polyphenols Some of the reasons include ... 

Plants are the other major source of naturally occurring mutagenic/carcinogenic agents (Table 6). Extracts or chemical compounds from a variety of plants have been shown to possess mutagenic/carcinogenic activity, including cycasin from cycad nuts, bracken from ferns, flavonoids from a variety of plant sources, hydrazine derivatives from mushrooms, and safrole from sassafras oil. 

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