A science project gone awry.
A young girl named Elise was assigned a science project. Her grandmother suggested she grow a sweet potato vine: it’s easy, simple, requires few tools, and you can see the results in a short period of time. So Elise carried out the experiment just as instructed. After 3 weeks, however, there were no sprouts.
Thinking she just got a dud, Elise’s mother took her back to the grocery store and they spoke with the produce manager.
He explained that they shouldn’t have expected the sweet potato to sprout because it would have been sprayed with “bud nip” (scientific name: chlorpropham) during processing, which prevents sprouting.
So Elise’s mom bought an organic sweet potato at the grocery store and Elise recreated the experiment with the new vegetable. Four weeks later, there were “vines” on the sweet potato—not worthy of Tarzan, but definitely viable.
Still not satisfied, Elise and her mother wanted to try the experiment one more time—this time with a sweet potato from a local whole-food, organic market. Watch the 2 ½-minute video to see the results.
Elise Uncovered Several Issues with her Simple Science Project.
Conventional produce with a tendency to sprout—like potatoes, onions, blueberries, spinach, beets, and cranberries—are routinely treated with a chemical to prevent sprouting.
This is presumably done for two reasons: to extend shelf life and preserve aesthetics. Of course, any chemical used commercially in the United States must be approved by the appropriate governmental body, so the Environmental Protection Agency has reviewed and approved the use of chlorpropham on fresh produce.
While no deaths have been reported as the result of ingesting this chemical with their root vegetables, there are still health implications.
In 1996, the National Pesticide Information Center had this to say about chlorpropham:
“Chlorpropham is a General Use Pesticide (GUP). The U.S. Environmental Protection Agency classifies it as toxicity class III – slightly toxic. Products containing it bear the Signal Word CAUTION.”
Worth a Second Look
The Food and Drug Administration’s equivalent in Europe, the European Food Safety Authority (EFSA), periodically reviews chemicals if new concerns are raised regarding its safety.
In 2012, the EFSA reviewed chlorpropham. The panel decided to exclude this chemical from its list of safe compounds because it felt the current research was inadequate to determine its safety for human consumption. Further, it recommended:
“If the above reported data gaps are not addressed in the future, Member States are recommended to withdraw or modify the relevant authorisations [for chlorpropham] at national level.”
This is just one of any number of chemicals to which non-organic produce can be subjected. Every year, the Environmental Working Group (EWG, a non-profit organization) studies the most popular fruits and vegetables and reports on the safety of the individual foods as it relates to pesticide residue.
It puts together a “Dirty Dozen” and a “Clean Fifteen” to help consumers make educated choices. This year, EWG had this to say about potatoes:
“The average potato had more pesticides by weight than any other food.”
Spinach and potatoes made the Dirty Dozen (those foods retaining the most residual pesticides of forty-eight vegetables and fruits tested)—not an honorable list to make.
So if you add the pesticide still clinging to a piece of produce to a chemical designed essentially to make it stop growing, that’s what’s on your food before you take it home.
A study published in the Journal of Agricultural and Food Chemistry tested the residual levels of chlorpropham on tubers and potatoes after harvest and found that the residues decrease over time but were still present 65 days after application of the “bud nip”. In addition, it’s difficult to effectively get rid of the stuff:
“Peeling removed 91−98% of the total residue; washing reduced residues by 33−47%. Detectable residues were found in boiled potatoes and the boiling water, and in french fries and the frying oil.”
A report published by Agriculture and Consumer Protection in 2005 detailed experiments using chlorpropham performed on various mammals. The purpose of the study was to find the levels of toxicity—which they did.
The levels varied by animal and the length of each experiment but the bottom line is that this chemical is toxic to mammals in different ways and at different levels, including effects on the reproductive system, embryos, and carcinogenicity.
It’s Hard to Know what “Safe” Means Anymore.
It’s crucial to eat enough vegetables and fruits every day and there are understandably trade-offs. Knowing exactly what you’re dealing with is the first step in making the right decisions for you, every day.
Young Elise certainly did learn a lot from her science project. And so can we.