Expert dismisses grapefruit seed extract ‘false positive’ explanation


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Expert dismisses grapefruit seed extract ‘false positive’ explanation
Claims by a leading grapefruit seed extract product manufacturer that the detection of synthetic disinfectants in some products is related to a ‘false positive’ interpretation of analytical data have been rejected by a leading analytical expert.

A review published in the American Botanical Council’s journal HerbalGram​ revealed that “possibly a majority” of grapefruit seed extract products on the market contain synthetic disinfectant chemicals​.

The review is part of an ongoing series produced by the American Botanical Council-American Herbal Pharmacopoeia-National Center for Natural Products Research (ABC-AHP-NCNPR) Botanical Adulterants Program.

False positive

However, in an email statement to NutraIngredients-USA, Carolyn Pruett from NutriBiotic, a leading manufacturing of grapefruit seed extract-containing products, dismissed the allegations that the products contain synthetic disinfectants like benzethonium chloride and triclosan.

“The reason​ [that tests suggest the presence of these compounds] is that grapefruit seed extract is very similar in molecular weight to both benzethonium chloride and triclosan, both of which are effective disinfectants, but are toxic to human and animal life.

“Some tests for benzethonium chloride and methyl paraben come up positive (which is more correctly called a ‘false positive’) and the same is happening for triclosan.

“Such rumors are false, and are not a threat to those armed with accurate information. The reports are certainly bothersome, but they have produced ‘false positives’, not accurate profiles. 

“The vast body of evidence from many years of use by thousands of satisfied consumers, doctors, manufacturers, and veterinarians speaks most loudly against such reports. Citricidal and NutriBiotic GFSE are proven safe and effective products.”

Opposing data from ‘some of the best chemists’

Commenting on the review’s findings and NutriBiotic’s statement, James Neal-Kababick, director of the FDA and DEA registered & inspected lab Flora Research Laboratories, told NutraIngredients-USA that the USDA-ARS performed a study many years ago on grapefruit seed extracts and found the presence of benzalthonium chloride.

In comparison, an extensive study by ARS-USDA scientists on commercial grapefruit seeds found no evidence of these compounds because they were not there, he said. 

“I have extensively reviewed the papers, which are published in the ​Journal of Agricultural and Food Chemistry, and the USDA-ARS includes some of the best chemists I know,” ​said Neal-Kababick. “I have not found any issue with their data.”

“What I have found interesting about the product is that benzalkonium chloride or benzalthonium chloride was always found in each lot I looked at or others reported on. However, methyl paraben and triclosan were found intermittently. 

cGMP enforcement

“For years, the FDA has been overworked and underfunded so they could only focus enforcement resources on the most serious issues violations,” ​said Neal-Kababick.

“Now, as the cGMPs have rolled out in full and the FDA has increased funding, they are able to enforce the regulations more effectively as seen by the plethora of warning letters in the last several months. 

"Thus the argument that if the product was not legal it would not be on the shelves is not valid.”

In 2010, the US Food and Drug Administration (FDA) issued warning letters for several products including the Nutribiotic grapefruit seed extract noting that it makes drug claims​.

Related topics: GMPs, QA & QC, Suppliers

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