Food Dyes Used to Adulterate St. John’s Wort Extracts, New Botanical Adulterants Bulletin Reports

Adulterators are using food dyes to mask adulteration of the popular herb St. John’s wort (Hypericum perforatum). In a brand-new Botanical Adulterants Bulletin published by the Botanical Adulterants Program, author Allison McCutcheon, PhD, a Canadian herbal research expert, reports that researchers are detecting food dyes like Red #2 and Blue #1 in samples of St. John’s wort extracts-a problem that has been “documented only recently.”

Researchers have so far detected the following food dyes in samples of St. John’s wort: E123 Amaranth (FD&C Red #2), E133 Brilliant Blue (FD&C Blue #1), E110 Sunset Yellow (FD&C Yellow #6), and E102 Tartrazine (FD&C Yellow #5).

“The addition of these illegal dyes signals a deliberate effort to mask the substitution of [St. John’s wort] with other Hypericum species that do not have a history of safe use and may have decreased or no therapeutic benefits,” McCutcheon writes.

In addition, she notes, some of the dyes being used to adulterate St. John’s wort samples may not be legal in some countries. Amaranth E, for instance, is banned in the U.S. due to concerns over potential toxicity. And colors like Brilliant Blue E133, Sunset Yellow E110, and Tartrazine E102 are banned in some other countries or, in the U.S., require additional FDA batch certification.

“Adulteration of St. John’s wort extracts with chemical dyes is no accident,” said Mark Blumenthal, founder and executive director of the American Botanical Council (Austin, TX) and founder and director of the Botanical Adulterants Program, in a press release. “Detection of these dyes by use of appropriate analytical methods in industry laboratories is an important step in preventing the presence of fraudulent and ineffective extracts from being sold to consumers. This is one of the key objectives of our Botanical Adulterants Program.”

Stefan Gafner, PhD, ABC chief science officer and Botanical Adulterants Program technical director, noted, “The sale of St. John’s wort extracts containing undeclared food dyes has been reported by a number of analysts from industry and contract analytical laboratories. This type of adulteration is quite easily detected with appropriate analytical methods.”

To learn more about historic and current adulteration issues regarding St. John’s wort, read the latest Botanical Adulterants Bulletin here.

Also read:

Researchers Propose New Method to Detect St. John’s Wort Adulteration

A Warning Label for St. John's Wort?

Jennifer Grebow
Editor-in-Chief
Nutritional Outlook magazine
jennifer.grebow@ubm.com