WASHINGTON, June 4 (Xinhua) -- A popular non-nutritive sweetener known as erythritol may be an effective and human-safe insecticide, a U.S. study said Wednesday.
Erythritol, the main component of the sweetener Truvia, was toxic to Drosophila melanogaster fruit flies in a dose-dependent manner, according to the study published in the U.S. journal PLOS ONE.
The flies consumed erythritol when sugar was available and even seemed to prefer it, said the study, adding that no other sweeteners tested had these toxic effects.
"It is particularly promising because it is safe for human consumption, unlike other pesticides that have caused tragic accidental poisonings such as one that killed 23 Indian school children last year," researchers at the Drexel University said in a statement.
According to the researchers, erythritol, a naturally occurring sugar alcohol that is present in small amounts in many fruits, has been tested in humans at high doses and found safe to consume.
Meanwhile, it has been designated as a generally recognized safe food additive by the U.S. Food and Drug Administration since 2001 and is also approved as a food additive in many other countries.
The study began as a sixth-grade science fair project in 2011 when one of the paper's co-authors, Simon Kaschock-Marenda, who is now in the ninth grade, tried to test the effects of different sugars and sugar substitutes on fly health and longevity.
"After six days of testing these flies in our house, he came back to me and said, 'Dad, all the flies in the Truvia vials are dead...'" recalled Daniel Marenda, Simon's father and an assistant professor of biology in Drexel's College of Arts and Sciences and co-senior author of the study.
"To which I responded, 'OK...we must have screwed up somehow. Let's repeat the experiment!'"
Under more rigorous testing conditions in the lab, they replicated their result and found that flies raised on food containing Truvia lived for only 5.8 days on average, compared to 38.6 to 50.6 days for flies raised on control and experimental foods without Truvia.
Flies raised on food containing Truvia also showed noticeable motor impairments prior to their deaths, they said. "Indeed what we found is that the main component of Truvia, the sugar erythritol, appears to have pretty potent insecticidal activity in our flies," Marenda said.
"We are not going to see the planet sprayed with erythritol and the chances for widespread crop application are slim," said senior author Sean O'Donnell, a professor of biology and biodiversity, earth and environmental science in Drexel's College of Arts and Sciences. "But on a small scale, in places where insects will come to a bait, consume it and die, this could be huge."